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About this book

The proceedings collect the latest research trends, methods and experimental results in the field of electrical and information technologies for rail transportation. The topics cover novel traction drive technologies of rail transportation, safety technology of rail transportation system, rail transportation information technology, rail transportation operational management technology, rail transportation cutting-edge theory and technology etc. The proceedings can be a valuable reference work for researchers and graduate students working in rail transportation, electrical engineering and information technologies.

Table of Contents


Study on Catenary Current Harmonic and Traction Characteristics of New Type Electric Multiple Unit

Harmonic characteristics of catenary current and traction characteristics play so important role in the traction systems of electric multiple unit (EMU). Throughout the track and measurement of a new type EMU, this paper is aimed to analyze the harmonic characteristics of catenary current by Fourier transform method and figure out the curve of traction characteristics by electric power method. Test results indicate that the catenary current of the new type EMU are in low harmonic, whether the EMU is at the state of traction or braking. When the input power of EMU is above 5 MW, harmonic content of the catenary current is below 1% and total harmonic distortion rate is less than 3%. At the same time, equivalent disturbance current is below 1.5 A and power factor is above 0.98. In addition, the new type EMU has the similar traction characteristics as other EMUs.

Haibo Zhao, Ruijing Ouyang

Research on Optimization Strategy of Forced Convection Heat Dissipation for Super Capacitor Energy Storage Power Supply

The service life of the super capacitor is very sensitive to the temperature. In order to obtain the optimization strategy of forced convection heat dissipation for super capacitor energy storage power, the main factors affecting the efficiency of forced convection heat dissipation are analysed based on the heat transfer theory, and the main direction of heat dissipation optimization are determined. The numerical heat transfer calculation model is established by the method of computational fluid dynamics. The internal flow field and temperature field distribution characteristics of super capacitor power supply are analysed. And the influence of cold air volume flow rate, air outlet layout and super capacitor heat dissipation structure on the heat dissipation effect is calculated and compared. The results show that the super capacitor heat dissipation structure and air outlet layout are most obvious to the improvement of heat dissipation. The maximum temperature of super capacitor is reduced to 32.62 °C from 68.69 °C through optimization in the same ventilation air volume flow rate and temperature. The improvement effect is very obvious.

Jun Zhang, Zhongcheng Jiang, Jixiong Jiang, JingJing Chen, Li Zhou

Mechanism of Rectified Output Voltage Spike in Isolated Converter Under Wide Input Voltage

There exists high rectified output voltage spike in isolated transformer’s secondary, especially for the high frequency link auxiliary inverters under wide input voltage. It will lead to increased voltage stress and loss of switching devices, impeding the improvement of system’s reliable operation and conversion efficiency. In order to solve the root causes of rectified output voltage spike, the mathematical model of rectifier output voltage is established. Based on the model, the mechanism of voltage spike is explored, deriving two main reasons: one is the wide input voltage, and the other is the resonance between the transformer leakage and the rectifier diode junction capacitor. Consequently, it is more pertinent to address the problem and improve the system’s reliability.

Chunhui Miao, Huiqing Du, Fei Xiao

Distributed Energy-Saving Dynamic Matrix Control of Multi-locomotive Traction Heavy Haul Train

Due to the heavy haul train’s force condition is far more complex than the ordinary train, broken hook and decoupling situation will become potential danger in the operation of the train. The energy-saving operation of heavy haul train is of great importance for rail transport. In this paper, we will study the distributed co-control of heavy haul train from the aspects of reducing the load-bearing force during the operation of heavy haul train and reducing the energy consumption of heavy haul train. It is of great importance to ensure the safe and stable operation and energy saving operation of heavy haul train. In this paper, simulink is used to build the multi-locomotive multi-particle heavy haul train dynamic model. Based on the dynamic matrix control (DMC) algorithm to establish the multi-locomotive multi-particle heavy haul train dynamic matrix control system, the velocity curve is tracked and controlled. The coupler force, running displacement and energy consumption are obtained. The simulation results are compared with the results which under the PID control system.

Xiukun Wei, Jinglin Zhang

Research of Hybrid Energy Pack for Rail Transit

Low carbon, green and energy-efficient are the important development directions of railway transit. Based on the operational requirements of rail transit and the characteristics of various energy storage components, this paper introduces a new type of E-E hybrid drive technology with super capacitors and batteries, and proposes a new configuration structure of super capacitors and batteries. The power allocation method and the key technical requirements of the technology are described, and the DC/DC voltage control optimization method is proposed for the regenerative braking energy feedback. The energy package scheme can effectively improve the performance of rail transit operation, which can provide reference for other green power drive system design.

Yejun Mao, Yuan Long, Shengcai Chen, Xiangyuan Xiao

Instantaneous Voltage PIR Closed-Loop Control for the Auxiliary Inverter

As an important part of EMU (Electric Multiple Units), the auxiliary power supply system plays an important role in the normal operation of the vehicle. In order to improve the reliability of the auxiliary power supply system, this paper analyses the harmonics of the auxiliary inverter under nonlinear load and suggests that the 6th harmonic voltage components in the DQ synchronous rotating coordinate system can be controlled to achieve the simultaneous control of the 5th and 7th harmonic voltage components in the three-phase static coordinate system. The instantaneous voltage PIR (Proportion Integral Resonance) closed loop control method in DQ synchronous rotating coordinate system is researched to eliminate the voltage aberration caused by harmonics and ensure the quality of output voltage. Finally, the simulation results show that the design has achieved the desired objectives.

Xuefu Cao, Yong Ding, Ruichang Qiu, Yun Kang, Yang Yu

Comparative Study of Two Control Strategies for Capacitor Voltage Balancing in Three-Level Boost Converter for Photovoltaic Grid-Connected Power System

The three-level boost converter (TLBC) which is applied in the photovoltaic (PV) grid-connected power generation system has an inherent defect of the midpoint potential shift. This paper compares two control strategies which can solve the problem. They are duty cycle independent control strategy and pulse phase delay control strategy. Then the principles of the two control strategies are analyzed, and in order to carry out simulation experiments more accurately and quickly, the characteristics of the strategies are verified based on the co-simulation of PSIM + Matlab. The results show that the duty cycle independent control strategy has better performance under the condition of the bias voltage is larger.

Yiming Chen, Zhencong Li, Shuping Yang, Wen Xu, Lingling Xie

A Resonant Push–Pull DC–DC Converter

This paper presents a novel topology of a resonant push–pull DC–DC converter. The primary side of the transformer applies a traditional two-transistor push–pull circuit structure, while the secondary side of the transformer includes a circuit of duplex windings and a LC resonant voltage-double structure. The average output voltage of the converter is four times of the voltage-double resonant capacitors. The LC resonance of the voltage-double capacitors and the secondary leakage inductors of the transformer transfers the energy from the primary side to the secondary side. The circuit adopts the strategy of fixing turn-on time and frequency modulation method. All switches and diodes can achieve ZCS (zero current switching). The paper analyses every operation mode in detail. Because of symmetrical working of the secondary upper and lower windings of the transformer, it can be transformed into two-port network to analyze the AC equivalent circuit through fundamental analysis method. And on this basis, the paper deduces the gain characteristic expression of the AC fundamental wave, plots the curve of voltage gain with different frequency ratio m, excitation inductance/leakage inductance ratio h and quality factor Q by MATLAB, and utilizes the voltage gain curve to design the circuit experimental parameters. At last, a sample converter of 20–28 V input/360 V output/rated power 400 W is built and tested. The experimental waveforms verify the correctness of the circuit and validity of the gain model. The experimental conversion efficiency indicates that the switch achieves ZCS to reduce the switching loss of existing push–pull circuit effectively and improve the conversion efficiency. The measured efficiency was 93.5% at rated load.

Shiying Yuan, Zhe Tang, Jiyun Tian, Hui Cao

Distribution Network Planning Considering DG Under Uncertainty

With the rise of a new round of energy revolution, the distribution network with distributed generation (DG) has become an important form of the future power grid. However, DG itself has the characteristics of randomness and intermittence, which brings impacts and challenges to the distribution network planning. Based on the uncertainty theory, the fuzzy simulation of DG and load are used to model the distribution network. The model takes the minimum annual investment cost and the minimum cost of network loss as the optimization target. Single parent genetic algorithm based on spanning tree is optimized and verified by 18 node system simulation.

Yanfei Liu, Hui Zhou

Reliability Evaluation of Inverter Based on Accelerated Degradation Test

In order to evaluate the reliability of the inverter, this paper adopted sequence and stress accelerated degradation test of a certain type of inverter. Take the voltage as the accelerated stress, setting 0.8 as the linear growth proportion coefficient of stress levels, through the detection of the inverter IGBT collector emitter voltage state and diode voltage to judge the wear condition of the inverter. The accelerated model is obtained through analyzing the test data, and the model parameters are estimated by the least square method. At the same time, the reliability of the inverter is evaluated, and the reliability curve is obtained. Finally, the reliability at the normal stress level is solved through accelerate model. In order to evaluate the effectiveness of Bayes reliability analysis of inverter, the Monte Carlo simulation about accelerated test is done, simulation results and evaluation results are similar. It shows that the accelerated degradation testing data is valid. The evaluation method can be used to evaluate the reliability of other power electronic devices in the rail transit vehicle .

Xinghui Qiu, Jianwei Yang

Analysis and Elimination of Early Failure of CNC Grinding Machine

The problem of early failure of domestic CNC grinding machine is studied herein. Minitab is used to analyze the machine fault data collected, and the best fitting function about it is obtained. On the basis, the early failure period about the machine is found, and the fault data in the early failure period is also analyzed by FMEA. Meanwhile, the main fault location, fault mode and fault reason in the early failure period of the machine are obtained. Some measures to eliminate the early failure, which are related to the self-made parts, purchased parts and enterprise management, are proposed. These studies lay a foundation for improving the reliability of the series machine.

Yulong Li, Genbao Zhang, Yongqin Wang, Xiaogang Zhang, Yan Ran

Reliability Fuzzy Comprehensive Evaluation of All Factors in CNC Machine Tool Assembly Process

There are many complex factors for the reliability of CNC machine tool assembly process. For this question, reliability factors system of a CNC machine tool assembly process is established by analyzing systematically and comprehensively using 5M1E method. For lots of uncertainties in evaluating the reliability of the CNC machine tool assembly process, a multiple target multi-level fuzzy comprehensive model is established by fuzzy mathematical theory. At the same time, the relationship of common reliability and fuzzy reliability is found, and weights of the various factors are obtained by expert scoring method and AHP method. The overall level of CNC machine tool reliability can be grasped by reliability comprehensive evaluation of its assembly process. Lastly, a certain type of CNC lathe is taken as an example to illustrate the validation of the model.

Xiaogang Zhang, Genbao Zhang, Xiansheng Gong, Yulong Li, Yan Ran

A Compacted Brushless Dual Mechanical Port Electrical Machine Model

A Pole-Modulation Brushless Dual Mechanical Port Machine (PMB-DMPM) model is presented. This model removes brush, the stator and its embedded winding are ordinary, the outer rotor is single-layer concentric cage, and the inner rotor is permanent magnets. By the modulating function of the cage rotor, the stator windings and the permanent magnets of the inner rotor produce a magnetic field individually, whose rotational speed and magnetic pole’s number are consistent with each other, and the energy can delivery through the stator, the outer rotor and inner rotor. The simulation results show that the machine model can achieve a good magnetic field modulation effect, and validate the proposed model’s feasibility.

Shaowei Wang, Zhenghao Wang

A Measurement Design for Pantograph Contact Force

Contact force between pantographs and overhead contact line used to evaluate contact quality should be measured properly. Nowadays, force sensors are usually assembled in pantograph head that appearance and dynamic performance of pantograph could be changed and influenced. To solve the problem, the authors designed a rod-type force sensor to replace the pantograph head pivot. At first, it is theoretically analyzed that force sensors can be placed not only in pantograph head but also in frame, and inertial correction is required. Aiming at a domestic pantograph, a force sensor was designed based on calculation. Furthermore, test results show great linearity and accuracy, which is over 90% with only inertial correction of pantograph head that satisfied the requirement of EN50317. With full correction, accuracy of the measurement system can reach 94%.

Yuan Zhong, Pengfei Zhang, Jiqin Wu

Cooperative Control of Voltage Equalization for Multiple Supercapacitors

In this paper, a cooperative voltage equalizer is proposed such that the voltages of supercapacitors in the power source achieve consensus. Voltage equalization for supercapacitors in the power source is a crucial issue since unbalanced voltage states would result in inefficiency and acceleration of lifetime decay. As multiple supercapacitors are connected in certain form, the power source can be modeled as a networked system. In this view, voltage equalization problem can be formulated as a consensus problem of multi-agent system. Combining cooperative control theory and Lyapunov method, a distributed controller is designed for each supercapacitor to drive its voltage synchronized to its neighbors in the network. It is proved that under the topology condition that the graph is connected, all voltages of supercapacitors can achieve consensus, i.e., voltage equalization of the power source is achieved. Simulation result has been presented to verify the effectiveness of the proposed controller.

Ying Yang, Yanlin Zhang, Yejun Mao, Junmin Peng, Fangrong Wu

Research on Electromagnetic Environment Safety of High-Speed Railway Catenary

The simulation of electromagnetic fields distribution around high-speed railway catenary on the platform by the finite element method. The research is based on simulation models as classification material properties of human body parts, and presents subdivision mesh sub-model method to calculate and simulate the frequency electromagnetic fields around the human, and giving a comprehensive evaluation on the safety of electromagnetic environment around high-speed railway according to national standard limit.

Huijuan Sun, Jun Liu, Can He

Application Study of Active Noise Control Technology for Rail Transit Vehicles

Active noise control (ANC) technology is a powerful complement for the traditional noise reduction technology. Analysed the current situation of noise control for rail vehicles; according to the application range of ANC technology, analysed the application strategy of ANC technology for rail transit vehicles; measured and analysed noise characteristics of an electric locomotive cab under different operating speeds and railway conditions, and proposed the ANC system scheme based on the whole cab space. Through the preliminary simulation calculation, the total sound pressure level in cab can be reduced by 4 dB(A). It provides a new idea for the noise control and comfort design of rail transit vehicles.

Xiaobo Liu, Jian Xu, Zhongcheng Jiang, Xianfeng Wang

DC Auto-Transformer Traction Power Supply System for DC Railways Application

In DC railways, the running rails are used as the return path for traction current, which inevitably leads to stray current and rail potential issues with poor insulation. However, the effects of existing solutions are limited, so DC auto-transformer (DCAT) traction power supply system (TPSS) is analyzed in this paper to solve the problems of stray current and rail potential fundamentally. Compared with the existing TPSS (E-TPSS), the mathematical analysis and simulation results show that DCAT-TPSS may solve both stray current and rail potential issues, which further reduce the voltage drop and power loss of power supply lines additionally.

Miao Wang, Xiaofeng Yang, Lulu Wang, Trillion Q. Zheng

An Optimized Method for the Energy-Saving of Multi-metro Trains at Peak Hours Based on Pareto Multi-objective Genetic Algorithm

Urban rail train starts and brakes frequently in it’s movement. It is important to improve the utilization efficiency of electric energy and reduce the traction energy consumption in the field of metro transit. At peak hours, the overlap time between two trains in the same power supply interval is longer and there is much more renewable energy generated by the train’s braking due to a large increasement in passenger flow and the number of departure. In this paper, a method based on pareto multi-objective genetic algorithm is proposed to optimize energy consumption. By optimizing the stopping time of trains in each station, train schedule is optimized and the regenerative braking energy can be used more efficiently.

Muhan Zhu, Yong Zhang, Fei Sun, Zongyi Xing

Optimized Discrete Model Based Model Reference Adaptive System for Speed Sensorless Control

In this paper, an improved inductive motor model reference adaptive system (MRAS) is proposed based on an optimized full-order adaptive observer. By using of an optimized discrete model of induction motor, the proposed method can be applied to the condition of low switching frequency. The rotor speed is calculated by an adaptive scheme and used as the feedback signal for vector control. The simulation results show that the modified version of MRAS enables accurate and stable performance of speed sensorless control.

Shaobo Yin, Yuwen Qi, Yi Xue, Huaiqiang Zhang, Dongyi Meng

NPV Control Method by Injecting Zero Sequence Voltage for Three Level NPC Inverter

The relationship of the zero sequence voltage and the neutral point voltage (NPV) is studied based on SPWM, in this paper. A new NPV control scheme by injecting a simple zero sequence voltage is proposed. The presented method does not require large collection of current and voltage signals, so it is very easy to implement. And the validity of the NPV control method is verified based on Matlab platform.

Bo Gong, Yang Liu

Analysis on the Vehicle Network Harmonic Oscillation and Its Influencing Factors of China’s Electrified Railway

With the rapid development of China’s electrified railway, vehicle network harmonic oscillation attracts more attention. The four-quadrant converter is an important part of the traction drive system. Based on its main circuit and control strategy, different vehicle network harmonic oscillation are classified by the mechanism and frequency into mediate-frequency harmonic oscillation and high- frequency harmonic oscillation. Their control loop transfer function are established separately and their main influencing factors are analyzed. Use the main circuit parameters of China’s electrified railway to establish a Simulink model. Analyze current wave and its FFT result to compare the harmonic oscillation situation. The simulation results verify the correctness of the analysis.

Yue Xu, Peng Lin, Shihui Liu, Fei Lin, Zhongping Yang

Impact of Rail Transit System on Grid Power Quality

As the issues of energy security, environmental degradation and traffic jam becoming more prominent, the rail transit is experiencing an unprecedented prosperity. However, rail transit is a special load system with “four-non” features which can cause the decline in power quality of grid, so it is more important to solve the power quality problems. In this paper, the basic structure of the public power grid and the power supply system of rail transit are introduced firstly. The types and characteristics of main loads are summarized, and the influence factors and potential hazards of the power quality problems are analyzed entirely. Finally, some solutions are proposed to solve each kind of power quality problems.

Zerong Li, Lei Han, Dejing Che, Qingxia Wang

A Torque Command Generated Method of Re-adhesion Control Based on Slip Acceleration

This paper proposes a new method of generating torque command for re-adhesion control by analyzing the mechanical equations of electric motor and train. The method of torque command is based on designing the reference slip acceleration without requiring a lot running control parameters and running test, so that the slip acceleration of the train in slip/skid state is negative and the amount of slip velocity can be theoretically determined. The effectiveness of the proposed method has been confirmed by the numerical simulation with high utilization ratio of adhesion force.

Long Qi, Guohui Li, Chenchen Wang

Research on Real-Time Simulation Modeling of Four-Quadrant Converter System Based on Basic Components

In the field of real time HiL (hardware-in-Loop) simulation of rail transportation traction electric drive system, in order to solve the problems that real-time simulation model, based on the equation of equivalent circuit state, occupies too many resources of system and lacks universality, and it is difficult to achieve on-line adjustment of variables. This paper presents the analysis and modeling of the basic components such as inductor, resistor, capacitor, four-quadrant convertor and so on. It realizes the real-time simulation of the four quadrant converter system. What’s more, the feasibility and effectiveness of the simulation model are verified by comparing the real-time simulation results with the experimental data.

Yunxin Fan, Huanqing Zou, Jin Fu

Robust H∞ Control of Single-Sided Linear Induction Motor for Low-Speed Maglev Trains

The single-sided linear induction motor has been used widely in low-speed maglev trains. In this paper, an H∞ control strategy under field orientation has been proposed to reduce the end effects and enhance the dynamic performance of the control system. First, the mathematic model of the SLIM is established. Then, the model is simplified, the end effects are attributed to the uncertainty of the system and the design is turned into an H∞ mixed-sensitivity optimal design. After that, an H∞ method based on internal model principle is proposed, by which a speed controller is designed finally. Simulation results indicate that a system with an H∞ controller has much better performance than that with a traditional PI controller.

Yifan Shen, Dawei Xiang, Jingsong Kang

Online Fault Diagnosis of the Hybrid Electrical Multiple Unit Traction Converter

In this paper, the signatures and the diagnosis approach of the failure of switching devices in Hybrid Electrical Multiple Unit (HEMU) traction converter (TC) are developed. In this paper, the distorted voltage and current with such failures are treated as disturbance exerted over normal voltage and current without failures, and a special analytical failure model is built for the expression of voltage and current disturbance. Combined with the failure model, this paper proposes a novel reasoning process to locate malfunctioning switching device. The reasoning process is based on object-oriented colored Petri Net (OOCPN). Digitalized failure signatures are taken as inputs into the OOCPN reasoning machine, what stimulates the brain activities during fault diagnosis of an expert.

Lei Wang, Mengzhu Wang, Yujia Guo, Ruichang Qiu, Lijun Diao

Characterization and Variable Temperature Modeling of SiC MOSFET

Silicon power semiconductor device is difficult to meet the requirements of high temperature, high pressure and high frequency. Among them, the MOSFET which has the fast switch speed and the simple driving circuit, become the most popular object in SiC power electronic devices. In this paper, we choose the C2M0160120D chip of CREE company, establishing a complete model. And the static characteristics of SiC MOSFET under different temperature points are simulated. The switching characteristics of SiC MOSFET under different driving resistances are analyzed and compared with the experimental results, and the accuracy of the model is verified in this paper.

Mengzhu Wang, Yujia Guo, Lei Wang, Guofu Chen, Ruichang Qiu

Calculation Analysis on Traction Motor Temperature Rise of EMU Vehicles Based on Fuzzy Neural Network

As a major consideration during the traction system design procedure, the traction motor temperature rise is also deemed as an important physical parameter for evaluating performance of the traction motor over the course of long-term service. Due to the operating conditions, ambient temperature and other factors, it is difficult to accurately assess the traction temperature rise during the designing process of traction system. On a basis of extensive data analysis on traction motor temperature rise tests, this paper first adopts the Heuristic method of Sequential Forward Selection to determine main factors that cause the traction motor’s temperature rises in various operating conditions. Then the fuzzy neural network calculation models of traction motor temperature rise is established under different working conditions. Training these fuzzy neural networks with sample data from route test to obtain the traction motor temperature rise calculation model under full operating conditions and the whole climate environment. Taking actual parameters of a certain type EMU (Electric Multiple Units) of the Beijing—Shanghai line as the object, this paper compares the temperature variation of the traction motor obtained from the simulation calculation with the experimental data in a way to justify the correctness and validity of the selected method.

Jianying Liang, Shaoqing Liu, Chongcheng Zhong, Jin Yu

Predictive Current Control for Three-Phase Asynchronous Motor with Delay Compensation

High performance control method which is able to improve the current inner loop performance is required in order to avoid the problem of the parameter setting of PI controller in vector control. And it will take time for controller to sample and calculate so there is a delay in the processing of the prediction model. Therefore, the paper proposes a model prediction current control with a delay compensation strategy for asynchronous motor drive. Firstly, the current prediction model under the rotating coordinate system is built using the asynchronous motor equation and the basic framework of current model predictive control is established based on the field orientation strategy. Also, the future trajectory of the current is predicted based on the linear fitting method. Then, aimed at a delay problem existing in the current predictive control, the paper proposes the delay compensation strategy to improve the adverse effects caused by a delay. And the simulation results verify the feasibility of the compensation strategy.

Yaru Xue, Jian Zhou, Yuwen Qi, Huaiqiang Zhang, Yong Ding

Predictive Direct Power Control of Three-Phase PWM Rectifier Based on Linear Active Disturbance Rejection Control

A dual closed loop for PWM rectifier, consisted of an inner instantaneous power loop and an outer dc-bus voltage loop, is presented in this paper. The inner loop adopts predictive direct power control (PDPC) and the outside one adopts linear active disturbance rejection control (LADRC) strategy. In order to achieve the expected switching voltage vectors, the instantaneous power values are forced to be equal to references at the next sampling instance in PDPC. The state space form can be established according to instantaneous active power balance equation, and then the generalized disturbance can be compensated. And the instantaneous active power reference can be achieved by LADRC structure. Finally, the presented structure is tested by simulation in Matlab/Simulink environment. And simulation results verified the feasibility and the effectiveness of the proposed system.

Kunpeng Li

Discussion on the Energy Efficiency and Electrotechnical Questions of Urban Cable Car System

Due to the convenience and low cost of cable car system construction, its application in urban public transport becomes more interesting. In the past, cable car systems were commonly used in non-urban areas, but now its application in urban areas requires more expert consideration. From the point of view of electrotechnical aspects, this paper studies the problems that may arise from the application of the cable car systems in urban areas, mainly from the aspects of energy efficiency, electromagnetic interference and electric corrosion. Also the technical compatibility of cable car systems with the high voltage transmission lines, photovoltaic plants and wireless communications is analyzed.

Lothar Fickert, Ziqian Zhang, Cunyuan Qian, Yanyun Luo

Test and Regression Analysis of Dynamic Shutdown Characteristic of High Power Thyristor

This paper focuses on thyristor in the aspects of its junction temperature, its zero di/dt, its forward current IT and its reverse voltage Vr, and presents in-depth study of internal factors which cause commutation failure of the valve. This paper puts forward the optimal configuration approach to the factors above, reduces various improvement measures to induce thyristor turn off time. A physical test platform of the shutdown characteristics is built. By testing the shutdown characteristics of thyristor, the linear regression analysis method is used to get the fitting formula of the thyristor turn off time.

Zhihao Zhang, Liqun Zhang, Zeng Shou, Yifang Jin, Yuhao Tan

Research on Mode-Switchover Process and Protective Circuit of Dual Power Supply System for Regional Express Electric Multiple Unit

This paper firstly puts forward the integrated traction equipment proposal of dual power supply system. Then it analyzes the catenary-pantograph relationship, the mode-switchover process and the risk of incorrect connection between the main circuit and power, then taking these as a measure, assesses the current collection and protective proposal according to the economic and industrial factors etc. Finally, on the basis of it, the preferred proposal is given.

Ruijing Ouyang, Haibo Zhao, Long Qi

Synergetic Control Design of EMU Parallel Motor

It is of great practical significance and wide application prospect to study the high performance multi-induction motor control strategy and control system by using advanced synergetic control theory. Combined with the principle of motor vector control and synergetic control, a parallel motor vector control system based on synergetic controller is designed. The system is more suitable for high-order, nonlinear systems than traditional vector control methods. The method not only can simplify the algorithm, but also can simplify the circuit structure, that is, to eliminate the traditional method of PI regulator, with better steady-state and dynamic performance. This paper verifies the above conclusion by stimulations in MATLAB/Simulink.

Chenhao Zhang, Tao Wang, Jikun Li, Kaidan Xue

Research on Thermal Management System of Lithium Iron Phosphate Battery Based on Water Cooling System

This paper analyzes the heat generation mechanism of lithium iron phosphate battery. The simulation and analysis of the battery thermal management system using water cooling is carried out. A cooling plate model in the thermal management system of water cooled battery was established. According to the simulation results of the cooling plate, Designed and developed a water cooled battery thermal management system. The experimental results show that the water cooling system has a better cooling effect, which can reduce the temperature gradient inside the battery box. All batteries are working in a stable environment, which is conducive to maintaining the consistency of the battery pack.

Liye Wang, Lifang Wang, Yuan Yue, Yuwang Zhang

Performance Comparison of Battery Chargers Based on SiC-MOSFET and Si-IGBT for Railway Vehicles

New type semiconductors, for instance, SiC-based switching devices, have many performance advantages over Si-based devices, including faster switching and lower power dissipation. In this paper, a research of an application of SiC-based MOSFET in a battery charger for railway vehicles is introduced, focusing on the performances of the charger. This battery charger is designed based on a silicon-IGBT-based charger. The new SiC-based battery charger has the same input and output rating with the original charger, but there’s an increase of switching frequency from 15 to 50 kHz. Therefore, a comparison between the two chargers from the aspects of efficiency, volume and power density is provided in this paper. It can provide some technical support for the design and application of high-power-density battery chargers in the auxiliary power system of railway vehicles.

Yun Kang, Zhipo Ji, Chun Yang, Ruichang Qiu, Xuefu Cao

A Research on VIENNA Rectifier Based on SVPWM Algorithm with Expected Voltage

At present, more and more power electronic fields have been applied to rectifiers. VIENNA rectifier is a new type of rectifier with wide application prospect. Compared with other rectifiers, VIENNA rectifier has a more simple structure. This kind of simple topology makes VIENNA rectifiers with many of the advantages that other rectifiers do not have. At present, there are many research and control strategies for VIENNA rectifier, in which the voltage space vector control strategy has better control effect. In this paper, a SVPWM modulation algorithm based on expected voltage is proposed for three-level VIENNA rectifier. What’s more, the realization of the modulation strategy and simulation results is given in this paper.

Changjun Guo, Gang Zhang, Xibin Bai

Research of Induction Motor Model Considering the Variation of Magnetizing Inductance

Accurate induction motor mathematical model is the cornerstone of the high-performance vector control of motor. Magnetic saturation can easily affect motor parameters, and the relation of magnetic saturation and the motor parameters is important to the establishment of the motor model. This paper derives a mathematical model of induction motor considering the variation of magnetizing inductance, based on the ideal mathematical model and magnetic saturation characteristic of the motor, from no-load test. Then, the motor model proposed and the ideal model in the MATLAB/Simulink Power System Block are respectively applied to the motor control simulation, and the experimental data are compared to verify the feasibility of the model designed.

Yujie Chang, Yi Xue, Yang Guo, Jing Tang, Dongyi Meng, Hui Wang

Auxiliary Inverter of Urban Rail Train—Oscillation Suppression Method of Induction Motor Load

Suppressing the induction motor load oscillation of auxiliary converter in urban rail train is very important to ensure the quality of train power supply and the operation stability. Firstly, this paper analyzes the energy state of the auxiliary converter. Then, according to the mechanical characteristic curve of the induction motor, the unstable operating area of the motor is discussed. After that, a method based on the inverter output frequency compensation by detecting DC side voltage is proposed, resulting in controlling the energy state and suppress induction motor load oscillation. Finally, the effectiveness and practicability of the method are full verified by simulation and experiments.

Hui Wang, Zhigang Liu, Shaobo Yin, Dongyi Meng, Yujie Chang

Improved Voltage Model Based Flux Observer Design for Traction Induction Motor

In traction control, accurate observation of the flux is critical to achieve high performance control of the motor. This paper first summarizes the commonly used flux observation method, and analyses the working principle and existing problems of the commonly used voltage model flux observer. Then, an improved voltage model flux observer is designed, which series high-pass filter and low-pass filter. The compensation algorithm of amplitude and phase error due to the introduction of the filter is deduced, which eliminates the integral saturation problem caused by DC bias and realizes accurate observation of flux. Finally, the simulation and experimental analysis are carried out to verify the feasibility of the improved voltage model flux observer.

DongYi Meng, Lijun Diao, Shaobo Yin, Yujie Chang, Hui Wang

Design of Median Machine in Battery Test System

The three-level structure composed of upper, median and lower machine is applied in battery test system (BTS) in this paper. The median machine in this BTS is designed and realized. CAN bus is used to communicate with each other between the upper and the median machine. RS-485 bus is used between the median and the lower machine. When the upper machine is online, the median machine can parse battery test instructions, store and send them to the lower machine. When the upper machine transits to offline state, the median machine can control the lower machine to continue battery test. When there is not an upper machine in BTS, the median machine can independently create and edit battery test and control the lower computer to complete test.

Jianan Chen, Jiuchun Jiang, Jingxin Li

The Research on Bi-Directional DC/DC Converter for Hybrid Power System

In the hybrid power system, the bidirectional DC/DC converter, as the driving devices for energy storage element, is the core element of hybrid energy storage system and has the function of stabilizing the intermediate DC link voltage. This paper introduces the working principle and the derivation of bidirectional Buck/Boost converter in the process of modeling. A voltage and current double closed loop control system based on load current prediction is designed. When the load changes constantly, the response speed of the system can be improved. Simulation studies using MATLAB/Simulink show that the established model and control strategy can be used for further research.

Guodong Liu, Zhipo Ji, Ruichang Qiu, Xiang Wang

Experimental Study the Electric Braking Anti-skid Performance of Electric Multiple Units

When an electric multiple units (EMU) runs on a long heavy downgrade track, electric brake failure may occur during the anti-skid control process, which would result to longer pneumatic braking time, high brake pad temperature and wear, etc. Thus, it is important to determine optimal strategies for the anti-skid control of EMUs through field experiments. In the present study, a method of spraying anti-friction fluid was adopted to simulate rail surface conditions with low adhesion. This would allow low adhesion conditions and enable the EMU to continuously operate on it. Then, control parameters and strategies were constantly adjusted to obtain the optimal glide. The field experiment revealed that it is feasible to reduce electric brake failure times and improve electric power flow by optimizing the anti-skid control strategy.

Baomin Wang, Xiang Gao, Yongfong Song, Yi Zhou, Yang Lu

Performance Test and Evaluation Technology Research of Photovoltaic Power and Energy Storage Generation System

In recent years, the capacity of distributed generations has a rapid growth, high penetration of distributed generation technology is facing new problems compared to the traditional distribution network. Therefore, it is necessary to evaluate the grid-connection before the distributed power source is connected to the grid. In this paper, based on the actual distributed photovoltaic and energy storage power generation system, the power control capability and response speed of the hybrid energy storage system are tested, The grid-connection of hybrid energy storage system and photovoltaic power generation system under smooth fluctuation, tracking plan instruction and peak to valley power generation scenario is evaluated, Provide a reference for the follow-up of distributed generations collocation network evaluation technology.

Na Li, Kai Bai, Zhi Li, Jian-ming Dong, Jin Zong, Yu Gong

Research on Ice-Melting Technology of Urban Rail Transit Catenary Based on Energy Cycle

When the train is running, if the catenary is heavily covered by ice, there will be arcs between the pantograph and the catenary, resulting in the train to be powered abnormally, even causing major accidents such as catenary breaks and pantograph damage. This paper proposes an ice-melting scheme based on energy cycle which is formed between the medium voltage grid and the icing catenary. The current of the catenary is controlled over the ice-melting current, which produces Joule heat to melt the ice. This paper analyzes the working principle and control strategy of the ice-melting system, calculates the ice-melting current, verifies the effectiveness of the control method and realizes the expected energy cycle by simulation.

Jian Liu, Gang Zhang, Fengjie Hao, Zhigang Liu, Xibin Bai

The Key Design and Control of Single-Sided Linear Induction Motors (SLIMs) Based on Serial Equivalent Model (SEM)

The Serial equivalent model (SEM) of short-primary linear induction motor (SLIM) was established. Impedance parameters was theoretical analyzed, and primary input frequency, current, power, thrust, factor-efficiency were iteratively calculated. The overall performance of SLIM was evaluated according to given top indicators. Two-dimensional and three-dimensional finite element analysis (FEA) were carried out, and the results were compared to the actual application tests to verify the consistency of design and real get.

Jiangming Deng, Qibiao Peng, Tefang Chen, Laisheng Tong

A Controller Based on Electric-Charger Balance Theory for Front-End Converters

Aiming at the problem that between the second harmonic current i2nd and dynamic response characteristic of the middle bus voltage ub of the two stage inverter, the charge balancing controller integrated with the traditional double-loop controller is proposed. The traditional controller operates as load stable to suppress the secondary harmonic current i2nd, but the load switched by the new controller. Based on the traditional double-loop controller, the design of the voltage-loop controller that meeting requirements of i2nd is expounded, containing the influence of cross frequency ωc on Δub and the final dynamic response time ts of ub. The working principle of the electric-charge-balancing controller and some other key design issue are described. A prototype of 450 W is built to verify the correctness of the theoretical analysis and the feasibility of the new converter.

Yisheng Yuan, Xianglong Mei, Pan Zhou, Jiyun Tian

Research on Energy Management for Hybrid EMU

The operation route of EMU is relatively definite, the operating condition can be predicted and planned, and the applicability of logic threshold is relatively good. Therefore, the rule based on logic threshold energy management strategy is adopted as a control strategy in this paper. Depending on the operating characteristics of hybrid EMU, this paper develop the logic threshold energy management control strategy based on rules considering of integrated fuel consumption, and make the simulation model of specific control method and speed control of diesel generator and battery charge and discharge control, then the hybrid energy management strategy of different mode have been achieved.

Rongjia He, Chen Zhang, Ruichang Qiu, Lijun Diao

Anti-circulation Strategy of the Hybrid Traction Power Supply Device Used in Urban Rail Transit

In urban rail transit, when the train running, the AC voltage fluctuates, which resulting in the instability of DC side voltage of the rectifier unit. The hybrid traction power supply consists of a 12-pulse rectifier unit and a four-quadrant converter device (4QC). Aiming at the problem of circulation between the rectifier unit and the 4QC unit of the hybrid traction power supply device, the possible causes of the circulation are analyzed. The output voltage characteristics and basic structure and the working principle of the hybrid power supply device are studied. Then putting forward the corresponding anti-circulation strategy, and through simulation and test to verify its effectiveness. And the strategy adjusts the voltage value automatically according to the actual situation without manual operation, which is very practical.

Lu Ming, Gang Zhang, Fengjie Hao, Xibin Bai

Comparison of Harmonics Between SVPWM and SHEPWM

The traction system of rail transit has the characteristics of low switching frequency and wide speed range, and generally adopts “asynchronous modulation + synchronous modulation + square wave” full-speed range pulse width modulation strategy. In order to realize the smooth transition from asynchronous modulation to square wave modulation, many excellent modulation methods have been developed in the past 30 years. This paper focusses on researching the space vector pulse width modulation and the specific harmonic elimination pulse width modulation. The principle of the two methods and its harmonic calculation methods are introduced, two methods have different advantages, people should choose their own modulation as needs. Simulation proves the feasibility of the modulation strategy.

Ruizheng Ni, Miao Sha, Jia Xiaoguang, Yong Ding, Jie Chen

Parameters Offline Identification of Induction Motor in High-Power Converter System

Currently the induction motor control system uses vector control widely. If the motor parameters adopted in vector control algorithm do not match with the actual motor parameters, there will be a significant impact on the control performance. Therefore, it is necessary to identify parameters before running an induction motor whose parameters are unknown and provide precise initial value for the online identification. This paper investigates a method with DC experiment, single phase AC short-circuit experiment and no-load experiment to identify the parameters of an induction motor. And the compensation of the output voltage which results from dead time, turn-on and turn-off delay and drop voltage of IGBTs and Diodes is studied in this paper. Identified results in both simulations and experiments are given to validate the method.

Miao Sha, Lailai Shen, Jie Chen, Jing Tang

Research on Construction Method of “Train-Traction Network” Harmonic Model for High-Speed Railway

Network-side converter of high-speed train produces high harmonics in the modulation process, which are injected into traction network in the course of the operation which may cause resonance. In order to analyze the resonant characteristics of the traction drive system, it is necessary to construct the “train–traction network” harmonic model.

Guorui Zhai, Lingmin Meng, Jie Chen

Research on Unbalanced Load Suppression Method of Auxiliary Inverter

This paper focuses on how to suppress the effect of unbalanced load on the output voltage distortion of the auxiliary inverter. The auxiliary inverter in this paper uses a split-capacitor inverter topology with a midline inductor to suppress the effect of unbalanced load. In this paper, the auxiliary inverter is split into three independent single-phase inverters, respectively, to control the fundamental impedance of each single-phase inverter to obtain excellent output voltage waveform. Each single-phase inverter control system uses voltage and current double-loop control strategy, the voltage outer ring with a new resonant controller, not only can inhibit the unbalanced load on the auxiliary inverter output voltage distortion, and can balance the split capacitor voltage. Finally, a virtual DSP system based on S-Function is constructed. The simulation results show that the new resonant controller can suppress the effect of unbalanced load on the output voltage distortion of the auxiliary inverter.

Yong Ding, Linghang Huang, Jie Chen

Hierarchical Control and Harmonic Suppression of a Vehicular Based Microgrid System

This paper presents a hierarchical control and harmonic suppression strategy for a vehicular based microgrid system, which is utilized as an ac mobile power station supplying both pulse power loads (PPLs) and nonlinear loads (NLs). In order to reduce the impact of the PPLs on the microgrid, a hybrid storage system consisted of battery and super-capacitor was designed to be paralleled with the diesel generator through a dc bus. Hence, the stability of the dc-bus voltage can be enhanced. And the size of the generator turbine can thus be dramatically decreased. To reinforce the uninterrupted operation capability of the power station, the vehicular microgrid was hierarchically controlled in two levels, i.e., the system level and converter level. Moreover, an improved vector control was proposed to deal with the current harmonics introduced by the NLs. The effectiveness and feasibility of the proposed control were initially verified by simulation results.

Shuguang Wei, Hailiang Xu, Qiang Gao, Xiaojun Ma

Research on Vector Control of Long-Primary Permanent Magnet Linear Synchronous Motor Based on Voltage Feed-Forward Decoupling

The dynamic response characteristics of current loop in vector control system is closely related to the realization of vector control strategy. In the system model of multiple motors connected in series (which consists of coupled section, uncoupled section and feeder cable), the inductance and resistance of uncoupled section and feeder cable are taken into consideration in this paper. Due to the ignoring of current coupling problem of d-q axis in traditional PI current regulator, the dynamic performance of the system is poor. To solve this problem, a modified PI regulator based on voltage feed-forward decoupling is applied to build the control system of permanent magnet linear synchronous motor (PMLSM). The model of traditional PI current regulator and the model of modified PI current regulator are built respectively and compared with each other in Matlab/Simulink. The simulation results verify the correctness and effectiveness of PI current regulator with voltage feed-forward decoupling, and indicate that this improved control system has better dynamic and static characteristic than traditional control system.

Zheng Li, Ruihua Zhang, Yumei Du, Qiongxuan Ge

The LCL Filtering Scheme of High Power Four-Quadrant Converter Used in Urban Rail Transit

The regenerative braking energy of the train can be fed back to the medium voltage AC grid by using the high power four-quadrant converter, which has a good energy saving effect. But the traditional single-inductor filter is very large in size. In order to suppress the current harmonics, and reduce the volume and cost of the filter, the LCL filtering scheme of the large power four-quadrant converter for rail transit is introduced in this paper. The design method of LCL filter parameters is presented, and the damping control methods are studied. The filtering effect and stability of the proposed filter are verified by simulation.

Dongsheng Xu, Gang Zhang, Fengjie Hao, Zhiqiang Hu

Performance and Thermal Analysis of Five-Phase Linear Induction Motor Optimal Control

Linear motors are featured with direct linear motion, but it has a low torque density due to the presence of edge effects. The torque density of five-phase linear induction motor can be improved by injecting high order harmonics of the magnetic field. The purpose of the paper is to present the optimal control strategy of a five-phase linear induction motor based on a rotor-flux-oriented control scheme, which promoted the performance of linear induction motor. The proposed control scheme is confirmed using finite element modeling and experimental tests. And the temperature distribution of the LIM shows temperature rise of the motor under this strategy is within the specified range.

Tao Tong, Jinlin Gong, Yadong Gao, Nicolas Bracikowski

Thermoelectric Coupling Analysis and Thermal Protection for Busbar Trunking System

Generators with water-cooled stators and water-cooled rotor windings are often with aluminum conductor flat wires, which are close to the surrounding steel frame structure (SFS). The magnetic fields, generated by the strong alternating current in the busbar, can lead to eddy current losses in the steel structure and reduce its life cycle costs. In this paper, the influence on the SFS by the busbar is analyzed by using the finite element method. Firstly, the temperature distribution of the SFS is obtained through the coupled analysis of both magnetic field and the thermal field. Secondly, the thermal-protection measures are proposed and optimal designed in order to protect the SFS from overheating.

Xiaodong Yin, Tao Tong, Yujiang Li, Jinlin Gong, Xiaohui Wang

Simulation of Short-Circuit Fault Occurring on Subway Train

Recently, with the large-scale development of subway, the safety of subway operation is attracting universal attention of the society. A short-circuit fault is a serious accident that threatens the safety of subway operation. The existing research focuses on the short-circuit fault occurring on the overhead line, but research on the short-circuit fault occurring onboard the subway train is rare. In this paper, a MATLAB/Simulink short-circuit fault model is built based on actual parameters of the subway train and the DC traction power supply system with MATLAB/Simulink platform. The currents of several branches are investigated through the simulation. The simulation result provides useful data when verifying the stability of electrical equipment and the accuracy of relay protection.

Lei Sun, Mingli Wu, Jixing Sun, Shaobing Yang

Research on Vehicle’s Combination Dashboard Diagnostic Protocol Stack

As the development of Vehicle Electric and Electrical system, Vehicle’s digital Combination Dashboard which can be used to learn about the whole vehicle’s parameters by driver has made an important role in the reliability of whole vehicle. So it is necessary for us to acquire the whole vehicle’s parameters and faults by realizing the on line and off line diagnosis of the combination dashboard. This paper develops a diagnostic design approach for vehicle’s digital combination dashboard on the basis of ISO 15765. It has realized the on line and off line diagnosis for vehicle’s combination dashboard in order to detect the vehicle’s parameters and faults conveniently. The experiment proves that the diagnostic protocol stack is efficient and reliable, it can greatly increase the speed of maintain service for engineers.

Yanming Li, Feng Gao, Yongliang Ni, Tingting Wu

Optimization and Scheduling Strategy of Energy Storage in Urban Rail Traction Power Supply System

In the urban rail traction power supply system, the load power fluctuates greatly, and the regenerated braking energy waste is serious. The fluctuation of load power can be stabilized effectively, and the utilization ratio of renewable energy can be improved when the energy storage system is applied in traction substation. Firstly, based on the load characteristics of traction substation, the minimum operation cost of energy storage investment is taken as the optimization objective, and a hybrid optimization method of traction substation based on ant colony optimization algorithm is proposed. Then, a hybrid energy storage real-time scheduling strategy based on wavelet packet decomposition algorithm is proposed, which can correct the wavelet packet decomposition results according to the real-time SOC state of the storage battery and super capacitor. Finally, the correctness and effectiveness are verified through the simulation results based on the measured data of a traction substation.

Wei Ma, Wei Wang, Ruonan Hu

Hierarchical Control Strategy of On-board DC Microgrid

In order to eliminate adverse impacts of instantaneous power loads, configurations, working principle and distributed power characters of on-board DC microgrid were analyzed. To maximize the function of this structure, a hierarchical control strategy was established based on wavelet transform strategy and fuzzy control strategy. And then, examples of application were carried out in MATLAB/Simulink based on a certain driving test cycle and simulation model to verify the effectiveness of the proposed strategy. The final results showed that the proposed strategy had an advantage in meeting demands of power loads. In the meantime, electric energy quality and battery service life could be significantly improved.

Luming Chen, Zili Liao, Hailiang Xu, Xiaojun Ma

Design and Simulation of Switched Reluctance Motor Control System

Based on the analysis of mathematical model of switched reluctance motor and the structure of drive system, position sensor model, power converter model, switched reluctance motor model and other models were established through Simulink module. Through a combination of these models, a system model of APC control was built. The simulation results show the stability of the control system, which provides a reference to physical system designs of such switched reluctance motor.

Chengling Lu, Gang Zhang, Chengtao Du, Junhui Cheng, Congbing Wu

Isolated Transit Signal Priority Control Strategy Based on Lane-by-Lane Vehicle Detection Scheme

In contrast to the conventional single-channel detection which uses all the detectors across all the lanes as a single input to a signal phase, the lane-by-lane detection monitors the gaps/headways on a lane-by-lane basis. In the conventional actuated control detection, detectors transmitted information to the signal control machine as long as they were triggered, but signal control machine can not distinguish which lane are they from. In the lane-by-lane detection proposed in this paper, detectors of each lane worked independently and transmitted information of each lane to the signal control machine separately. Based on the probability theory, models were derived for estimating the green extensions with various geometric configurations. Using the proposed models, green extensions for actuated signal controls can be obtained. By comparing the required green extensions of buses and social vehicles to determine whether to give priority to the bus signal. The lane-by-lane control strategy proposed in this paper were simulated by VISSIM. The simulation results showed that the lane-by-lane control strategy has a better control effect in different situations compared with the fixed time control strategy and conventional actuated control strategy.

Jun Deng, Liang Cui

Analysis of the Effect of a Color Image Encryption Algorithm

Because of multimedia information has huge amount of data and high redundancy, traditional encryption technology is not suitable for multimedia information encryption. Multimedia information encryption get great development when chaos appears. Chaos is very suitable for image encryption because of its many advantages. In this paper, I analysised the shortcomings of color image encryption algorithm based on 3D unified chaotic system, then aiming at the algorithm deficiency, I analysised the algorithm which improved by cat map, the security of the algorithm has been greatly improved.

Yukun Guo

Novel Affine Projection Sign Subband Adaptive Filter

In this paper, we propose a novel affine projection sign subband adaptive filter (NAPSSAF) algorithm which can obtain better performance than the conventional APSSAF. The proposed NAPSSAF is derived by minimizing the l1-norm of the subband a posteriori error vector rather than the overall a posteriori error vector, which fully uses the subband adaptive filter’s inherent decorrelating property. Simulations in context of the system identification and acoustic echo cancellation (AEC) are carried out to demonstrate the advantages of the proposed algorithms. The results of simulations demonstrate that the proposed NAPSSAF obtains faster convergence rate than the existing algorithms.

Qianqian Liu, Haiquan Zhao

Research on Redundancy and Fault-Tolerant Control Technology of Levitation Join-Structure in High Speed Maglev Train

The phenomenon occasionally occurs during the running of the high-speed maglev train that the suspension control unit fail to work. However, whether the suspension system is normal is directly related to the safety of the train. Therefore, the particular levitation join-structure is adopted in the high speed maglev train. This study is conducted to obtain redundancy and fault-tolerant control technology of levitation join-structure. The mathematical model of levitation join-structure is established and the suspension controllers are designed, so as to solve the failure problem of one suspension control unit and improve the reliability of the entire suspension system

Mingda Zhai, Xiaolong Li, Zhiqiang Long

Short-term Passenger Flow Forecasting Based on Phase Space Reconstruction and LSTM

In this paper, the chaotic characteristics of the railway passenger flow are considered, and the PSR-LSTM (Phase Space Reconstruction-Long Short Term Memory) model is proposed by the phase space reconstruction method to recover the hidden trajectory in the passenger flow. First, this model uses C-C method to calculate the time delay and embedding dimension, and carry out phase space reconstruction. Afterwards, the LSTM neural network is used to predict short-term passenger flow. In the experimental part, it is proved that the passenger flow data with chaotic characteristics are reconstructed by phase space processing can get more accurate predictions. Then, in order to further verify the accuracy of the model, this model is compared with the BP neural network model and the SVR model, which is also subjected to phase space reconstruction processing. The experimental results show that the model has high accuracy.

Yong Zhang, Jiansheng Zhu, Junfeng Zhang

Application of Improved Gaussian-Hermite Moments in Intelligent Parking System

The Gaussain-Hermite moments theory is applied to license plate recognition system in this paper. At the same time, the order of Gaussian-Hermite moments are improved by two-dimensional simulated annealing algorithm, the image reconstruction is achieved by obtaining characteristic moments. Experimental results show that the algorithm has high research value and application value.

Xing He, Lin Wang, Zhongyou Zuo

Research on Optimization of Passenger Volume Flow Monitoring Through the Metro Network Video Surveillance Technology

In order to manage the constantly increasing flow of metro passengers and speed up the response to passenger congestion arising from various emergencies in the metro system, the Beijing Metro Network Administration Co., Ltd. (hereinafter referred to as the “BMNA”) will begin construction of the Metro Network Video Surveillance Center (hereinafter referred to as the “Surveillance Center”). This essay analyzes the characteristics of passenger flow congestion in the metro system and the traditional method of passenger flow density monitoring. Based on the system requirements and initial design of the Metro Network Video Surveillance Center, this essay applies scientific principles and methods to make suggestions to improve the supervisory of passenger flow congestion, by proposing a systematic congestion pre-warning mechanism using refined Video Analytics technology. Its aim is to provide references and support for the establishment of the Surveillance Center in future.

Yuekun Zhang, Feng Xu, Tianxiang Mao, Bing Han

Adaptive Locomotive Headlamp System Based on Monocular Vision

How to ensure the safety of a locomotive is a crucial problem, when it moves in a curved railway at night. For solving this problem, a new adaptive locomotive headlamp system based on monocular vision is proposed in this paper. The method consists of two key steps. First, a single-camera is provided to capture the tracks in front of the locomotive, and an image processing algorithm is proposed to obtain the key related parameters. Next, combined with the position feedback signal of the headlamps and the parameters obtained in the previous step, an adaptive control method is proposed to rotate the headlamps. By this way, the light emitted from the headlamps will always be on the axis of the railway, thus ensuring the safety of the locomotive.

Juan Gong

Influence Analysis of the Grounding Grid of Communication Tower Base on Lightning Signal

Communication tower is often close to machine room. When the lighting strikes the communication tower, it raises electrical potential of grounding grid and transient ground potential raise could damage weak electrical equipment in machine room. In order to solve this problem, in this paper, a response calculation model under the condition of the lightning transient was established, which was based on the construction drawing of a communication tower and machine room grounding grid in Bao-Lan PDL (Passenger Dedicated Line). This model analyzed potential changes under the conditions of various factors when the lightning current injected grounding grid, including two grounding grid is equipotent connected or not, different distances and soil resistivity between two grounding grid, etc. Computational results show that transient ground potential of the machine room can reduce by 70% when the distance of two grounding grid increased from 5 to 20 m, and transient ground potential can be 10 times higher when two grounding grid is equipotent connected. Finally, the propose suggestions related to requirements engineering based on these analysis.

Jin Yang, Zhiyu Li

Simulation Model of Direct Power Supply System with Return Wire in Tunnel Section

Traction power system simulation is needed, not only before system construction or reformation, but also the sensitivity analysis for the parameters of existing line. Due to the special landscapes for tunnel section, parameter calculation method of wires in traction power supply system should be different from the other kinds of section. Take Wushaoling super long tunnel section as example, the simulation model of direct power supply system with return wire was built based on the multiconductor transmission line (MTL) theory. The characteristic impedance was used to dispose the end effect of the return current network, the impedance parameters of traction network were calculated through Tylavsky formulas. At last, Field tests were performed to validate the correctness of the simulation model, this modeling method could be promoted to the simulation of other tunnel sections.

Zhiming Liu, Jiangjian Xie, Zhixin Wang, Jin Yang

Application of Moving Average Filter to Train’s Active Control System

Based on the integrator drift problem of acceleration in active control system, a method using the moving average filter on the original acceleration signal was adopted, which filtered out the DC component of curve passing to ensure the active control system work properly. The principle of the moving average filter was illustrated, and some influencing factors of real-time filter were analyzed. Compensating the static error caused by the ramp function to the low frequency component, a high-pass filter with 0.2 Hz cut-off frequency was designed. Using the active control model of vehicle system, the designed filter was simulation analyzed. In addition, the filter was used to process the acceleration information measured on the actual line. The simulation and experimental results indicated that the moving average filter can effectively filter out the centrifugal acceleration of curve passing, and inhibit integral drift, without significant influence on the performance of the active control system.

Xu Wang, Jiaxin Ji, Peida Hu

The Simulation of the Longitudinal Force of Heavy Haul Trains

To improve the transportation capacity of the train, 10,000 tons level train is getting wide application and further research is required. Considering the significance of the longitudinal force and the synchronous control performance to the safe operation of the train, a simulation model on the longitudinal force of the heavy haul train is set up in this paper and theoretical calculations on longitudinal traction force, braking force, running resistance and coupler buffer force are conducted and then the whole process of the train starting to the train braking is simulated. Finally, the simulation test about the emergency brake of the heavy haul train is made to prove the feasibility of the simulation model.

Shize Huang, Qiyi Guo, Liangliang Yu, Yue Liu, Fan Zhang

Nash Bargaining Game of Cloud Resource Provision in Cooperative Market

Market economics can achieve optimal allocation of resource by the equilibrium theory, cloud resource provision mechanism based on market economics is studied. For increasing collective revenue further and improving the efficiency and fairness of resource allocation, a resource provision algorithm RPABG is proposed in bargaining market of cloud computing. RPABG builds the model with bargaining game and its objective is to find Nash bargaining solution (NBS). NBS is solved respectively in two different conditions by our proposed iteration algorithm. Simulation experimental results show that RPABG not only has a faster convergence speed, compared with our earlier work based on non-cooperative game, but can improve the overall utility of resource providers and realize Pareto efficiency, which can lead to an optimal allocation of cloud resource with fairness, rationality and equilibrium.

Xiaoqing Zhang

Research on the Method of Calculating Train Congestion Index Based on the Automatic Fare Collection Data

With the increasing operating mileage of the urban railway transit, the traffic volume of the urban railway network has risen sharply. In order to enhance the performance and safety of the urban railway transit, the research on the train congestion index is imminent. In this paper, firstly, the definition of congestion index is proposed, and the congestion degree model is formulated. Secondly, the real-time congestion degree of train lines is obtained by using the algorithm based on the spatial and temporal K-shortest path. Finally, the train congestion of Xi’an subway is analyzed and calculated by the model based on the data of passengers’ transportation cards and the process consumes just 3 min. Comparing with the actual results, we come to the conclusion that the train congestion model and space-time K-shortest path algorithm are correct and feasible, which can provide constructive suggestions on the operation and management of the urban railway network and the flow limitation of the station.

Wenxuan Zhang, Jinjin Tang

Research on Shortest Paths-Based Entropy of Weighted Complex Networks

In order to provide a new measure for the structural characteristics of complex networks, a new shortest paths-based entropy (SPE) is proposed to describe the influence of degree and shortest path on network characteristics in this paper . The novel measurement based on shortest paths of node pairs and weights of edges. Many different approaches to measuring the complexity of networks have been developed. Most existing measurements unable to apply in weighted network that consider only one characteristic of complex networks such as degree or betweenness centrality. To some extent, the shortest paths-based entropy overcome the inadequacies of other network entropy descriptors. The method combines node degrees with shortest paths. For the purpose of proving the reasonableness of this method, we carry on a contrast analysis of the SPEs of different type networks, including: ER random network, BA scale-free network, WS small-world network and grid network. The results show that shortest paths-based entropy of complex networks is meaningful to evaluation of networks.

Zundong Zhang, Zhaoran Zhang, Weixin Ma, Huijuan Zhou

Train-Mounted Head-up Display System Based on Digital Light Processing Technology

Rail transit has been playing an important role in public transportation. Ensuring its safety is a key issue in the field of rail transportation. HUD (Head-Up Display), an auxiliary system to improve drive safety, has been successfully applied in the automotive industry. In this paper, a study of HUD applied in the field of rail transmit is presented, followed by the structure and the working principle of train mounted HUD based on DLP (digital light processing) projection display technology. In addition, the feasibility of HUD used in the field of rail transportation is verified by experiments.

Ai-jun Su

An Effective Detection Algorithm of Zebra-Crossing

In order to improve the function of driver-assistance system, this paper proposes a real-time detection method of zebra crossing based on the on-board monocular camera, it doesn’t only detect the zebra crossings we can see from the road, but also detect some zebra crossings obscured by other objects. Firstly, integral method based on horizontal projection is used to separate possible zebra crossings from lane. However, the integral of other road traffic signs may be similar to a zebra crossing, in order to overcome this problem, the number of identifier are calculated respectively for each effective projection region, it is obvious that the number of zebra crossing are more than others, experimental results show that our method proposed in this paper is effective.

Zu Sheng Chen, Dao Fang Zhang

A Node Pair Entropy Based Similarity Method for Link Prediction in Transportation Networks

Link prediction is a challenging problem. It is an approach to determine the possibility of potential or missing link between node pairs in a network. Researches on transportation network’s link prediction are mainly about travel time prediction, path prediction, traffic flow prediction, congestion prediction and so on. However, current studies are restrained by direction of the link or a new route. To solve this problem, a node pair entropy based similarity method for link prediction is proposed. Firstly, the initial state of all nodes in the node pair are initialized. Then, the influence weights of upstream node to lower nodes and the feedback state are determined. So the uncertainty degree of a path is obtained. Finally, the link prediction of the unconnected node pair is measured by node pair entropy. This method differentiates the roles of different nodes, and the connection between the common points is considered. It becomes a good solution for transportation network’s link prediction.

Zundong Zhang, Weixin Ma, Zhaoran Zhang, Huijuan Zhou

Transfer Domain Class Clustering for Unsupervised Domain Adaptation

In this paper, we propose a transfer domain class clustering (TDCC) algorithm to address the unsupervised domain adaptation problem, in which the training data (source domain) and the test data (target domain) follow different distributions. TDCC aims to derive new feature representations for source and target in a latent subspace to simultaneously reduce the distribution distance between two domains, which helps transfer the source knowledge to the target domain effectively, and enhance the class discriminativeness of data as much as possible by minimizing the intra-class variations, which can benefit the final classification a lot. The effectiveness of TDCC is verified by comprehensive experiments on several cross-domain datasets, and the results demonstrate that TDCC is superior to the competitive algorithms.

Yunxin Fan, Gang Yan, Shuang Li, Shiji Song, Wei Wang, Xinping Peng

Nodes Deployment of Wireless Sensor Networks for Underground Tunnel Environments

Wireless nodes deployment is a key point for monitoring and localization of the trains in railway underground tunnels, which is critical to guarantee high-efficiency and safe operation of railway traffic. In this paper, based on the surface mapping and expansion theory, the mapping of 3D tunnel surface onto 2D domain is firstly investigated. Reliable communication links among the wireless nodes in localization are vital for successful data transmission. Then, the propagation pathloss, as well as the fading of radio signals transmitting in tunnel environments is analyzed. Also, the maximum transmission range of wireless nodes under the constraint of network connectivity is estimated according to the wireless link budget. The three grid-division (nodes deployment) in wireless sensor network (WSN), i.e., triangular-grid, square-grid, and rhombus-grid are obtained in the mapped 2D domain of actual tunnel.

Cuiran Li, Jianli Xie, Wei Wu, Yuhong Liu, Anqi Lv

Application of DBN for Assessment of Railway Intelligent Signal System Reliability

According to the variable structure characteristics of railway intelligent signal system (RISS) with different railway station scale, a new reliability assessment method based on Dynamic Bayesian Networks (DBN) is studied. A comparison between DBN model and probabilistic model is studied to verify the accuracy and correctness of DBN model. Based on DBN model, the static gates analyzing results deliver a calculation with no error, while the spare gate analyzing results deliver a calculation with a tolerable error that leads to more strictly and credible calculations. Meanwhile, this paper analyzes reliability indexes of RISS with four different railway station scale. The results show that: when the railway station scale increases, the reliability of RISS decreases, which has little impact on the ranking of the components’ Birnbaum importance factor and diagnostic importance factor.

Zhengjiao Li, Bai-gen Cai, Shaobin Li, Jiang Liu, Debiao Lu

Key-Point Feature Detection Method for Surrounding-Field-of-View Image Applications

This paper describes a robust feature detection method for omni-directional image which used for target and region-of-interest (ROI) detection. The omnni-directional system can provide much larger FOV (field of view) which can support 360° of the whole environment. Firstly, we briefly introduce the back-transformation model of the omni-directional system. Then, the Harris and SIFT (scale invariant feature transform) is applied to find the key-point features of the around area. Finally, we compared the above feature detection methods (Harris and SIFT) for the omni-directional image and its corresponding unwrapping panoramic-cylindrical and solve this matching problem with some experiment and discussion.

Mai Jiang, Qi cheng Yan, Cheng tao Cai

The Analysis of the Communication Distance in Wireless Optical Communications for Trains

Wireless optical communications is considered as a good way to provide big bandwidth for wireless communications. Therefore, the ground-to-train wireless optical communication can supply fast wireless communication service for running trains. In this paper, we demonstrate a system model to analyze and evaluate the communication distance in wireless optical communications for trains. After that, the simulation performance fully prove that the divergence angle and weather condition are two key factors that influence the communication distance. Moreover, the proper distance between two consecutive ground transceivers and the reasonable divergence angle are also displayed which have a significant meaning for guiding the deployment of ground transceivers.

Tairan Zhang, Jianghua Feng, Jiabo Xiao, Jun Tang

The Research on Route Search Based on Heuristic Strategy

Route search, actually in rail transit, is finding an accessible and safe route for train dispatching. Route search is the basic function of computer based interlocking system. The efficiency of route search and the correctness of the target route searched are of great significance to ensure the traffic safety. In view of the similarity between the railway yard and the directed graph, the railway yard will be modeled as a directed graph. In this paper, a new route search method, combining the depth-first traversal and heuristic strategy, has been proposed. Test results based on real yard show this method can quickly and accurately search target route. And it has high practical application value.

Cheng Wang, Shaobin Li, Yan Li, Ziwei Liu, Huiyong Liu

Active Compensation Method for Long Time Delay and Packet Loss in Networked Control System

To achieve required performance of networked control system, this paper proposes an active compensation method for long time delay and packet loss. The controller predicts multi-step future control inputs based on optimization algorithm. This strategy has less conservativeness than others because that the state feedback gain is not fixed, but a variable value depending on feedback delay. The compensator located in actuator side actively compensates the time delay and data packet loss. According the strategy, the rule is established for the selection of data packet and control input, the closed-loop system is modeled as a switched system. The simulated results confirm the analytical results given in this paper.

Wei Fu, Xianyi Yang, Ning Li

Urban Rail Transit Platform Passenger Alighting and Boarding Movement and Experiment Research

With the improvement of the urban rail transit network and the rights of passengers demand, passenger traffic continuously raised, the operation of urban rail transit with the rights to add pressure. For urban rail transit system, the station for line capacity plays a decisive role, while getting in motion in the station is a key part of the passenger flow in the platform. So, in this paper, we study focuses on the junction between the train and the platform of passengers getting on or off motion and its influencing factors. This paper uses orthogonal experimental method to design experiment. Using the simulation experiment platform and the simulation experiment of the simulation software, two methods are used to study the passengers’ on and off motion. The time of getting on and off is used as experimental index to evaluate the result of experiment. As a result, it is important to cut down the time of train stop, reduce platform congestion and reinforce the operation and management level of urban rail transportation.

Yang Li, Yanhui Wang

Research on Running Curve Optimization of Automatic Train Operation System Based on Genetic Algorithm

The running curve optimization of automatic train operation (ATO) system usually takes into account running time, energy consumption and passenger comfort. In this paper, in order to provide more comprehensive optimization and accurate reference of running curve for ATO system, we adopted the multi-objective optimization strategy of genetic algorithm (GA) to optimize from five aspects: speeding (safety), parking accuracy, punctuality, energy consumption and comfort. The GA optimization program is written by M language in MATLAB, and combined with a graphical user interface (GUI) tool to design the optimization system of running curve of ATO based on genetic algorithm. Its validity is verified by comparison between the tests based on three different interstation of Shanghai Metro Line 11. The results show that it is effective and practicability to use the designed system to optimize the running curve of ATO system.

Hao Liu, Cunyuan Qian, Zhengmin Ren, Guanlei Wang

Research on Tram Detector Location Based on Vehicle–Infrastructure Communication

Modern tram vehicle infrastructure system mainly relies on tram detectors to communicate with the trams, providing the basis for optimal control of the tram operation. This paper presents a calculation method to find the optimal locations of announcement detectors and request detectors based on characteristics such as system operation instructions, tram speed, signal priority strategy and manual operation habits. The critical location for detectors is proposed considering the intersecting-road hierarchy and the signal priority parameters. A sample model application and simulation experiments on a real-life intersection are included. Compared with the tram delay of different request detector locations, the outcome indicates that the most effective tram priority is determined when the detectors are placed according to the method proposed in this paper.

Huang Yan, Dongxiu Ou, Ziyan Chen, Yang Yang

Research on Real-Time Performance of Train Communication Network Based on HaRTES

With the development of rail transportation technology, the integration of train control multimedia information into a network has become the trend of the future. Ethernet can meet this demand because of its high speed, large bandwidth and so on. In this paper, the Hard Real-Time Switching architecture is introduced into the train communication network. The data communication of train communication network depends on many switches, so a multi hop scheduling algorithm based on hard-real-time switch is proposed in this paper to ensure the real-time performance of train communication network data transmission. Finally, according to the actual communication process, this paper built the train communication network topology. The OPNET simulation results show that the proposed scheme can satisfy the real-time requirements of train communication network.

Luyao Bai, Lide Wang, Jie Jian, Ping Shen, Chuan Yue, Xingyuan Wei

Data Cache in Mobile Environment Based on Extensible Markup Language

Based on the research of data caching mechanism, this paper aims at the method that uses extensible markup language (XML) to cache the mobile terminals data. Taking an open-pit mine truck dispatching system as an example, wireless LAN following the 802.11 protocol is used as the study background, and mobile terminals with data acquisition function is the study object. Against the phenomenon that the mobile terminal in no signal or weak signal area cannot properly connect to the network, XML is proposed to cache data. The cached data can be send to the server in time through real-time monitoring network connectivity status of the mobile terminal and ensure the timeliness of data transmission. Field test proved that the method has certain reference significance for similar work.

Jiusheng Du, Luyao Ma, Zheng Hou

Fully Automatic Operation System in Urban Rail Transit Is Applying in China

Fully Automatic Operation (FAO) is the highest level in the automation level of urban rail transit train operation and can reduce the security risk caused by human behavioral mistakes so as to provide more secure and efficient technical support for the urban rail transit operation. The FAO system is a complicated system and covers the whole lines and each station and train. This paper emphatically introduces development of the FAO system in domestic. FAO system will be applied to Beijing Metro Yan Fang line. Its application not only improves the automation level of technical equipment, but also comprehensively improves the technical level, the operation mode of rail transportation and the RAMS (Reliability, Availability, Maintainability and Safety) level of the whole rail transportation control equipment so as to ensure high-security, high-reliability and high automation operation under the unattended supervision situation. FAO system will be applied in several cities of the country in the near future, and it has a wide prospect of application in China.

Fei Yan, Bo Liu, Yao Zhou, Chunhai Gao, Tao Tang

Discrete Fuzzy Model Optimal Identification Based Approach for High Speed Train Operation

This paper investigates the problem of high speed train operation with special attention to minimizing the discrete constraint conditions between on-board traction network and group signaling equipment. A new discrete fuzzy model for train operation is developed, and its novelty lies in the fact that it optimizes the discrete model using relative degree criterion, which contains two processes of model order identification and model parameters local optimization. Then, we utilize a fuzzy weighted least square method to solve the global optimization problem of model parameters. In the end, simulation experiments have been implemented on the CRH2C-type high speed train, which validates the correctness of the proposed model.

Kunpeng Zhang, Chunlan An

Research on GIS Database Construction and Application for UGV in the Campus Traffic Environment

As the research hotspot of intelligent transportation system (ITS), unmanned ground vehicle (UGV) with high intelligence is able to reduce the probability of traffic accidents and traffic congestion, and improve the efficiency of urban transportation system. Environmental perception is one of the key research topics in the research of key technologies of UGV. The campus transportation environment, as a simple version of the urban transportation environment, needs to perceive as much traffic information as the urban traffic environment. At the same time, the geographic information system (GIS) has capabilities of strong geographical information storage and management, which can play a critical role in the environmental perception of UGV. In this paper, we study the autonomous driving of unmanned ground vehicle in the campus traffic environment, and the construction method of GIS database is proposed for the perception demand of UGV in the traffic environment of campus. Then, according to the GIS database, autonomous navigation control of UGV is carried out to verify its applicability and effectiveness. After testing, the GIS database proposed in this paper can assist the autonomous driving of UGV well and complete the driving tasks in the campus environment.

Mingtao Wu, Yanhui Wang, Xiaofeng Li

Research on Algorithm of Correlation Denoising Based on Wavelet Transform

Aiming at the problem of noise in the traffic monitoring, especially at night, an image denoising algorithm is proposed. Application of correlation denoising algorithm based on wavelet transform in traffic monitoring. Firstly, Haar wavelet is used as the transform matrix, then image data are denoised. And The similarity of the image is evaluated by the peak signal to noise ratio. Finally, the obtained data is compared with the algorithm of existing adaptive threshold. It is found that the improved algorithm of correlation denoising achieved the expected effect and can denoise the monitoring image of nighttime very well.

Lei Yang, Feng Xue, Hong hai Wang, Hua wei Cheng

Distributed Simulation Modeling and System Construction for the Networked Operation of Urban Railway System

Facing the situation of the large-scale network, we conducted the research and construction on simulation and system modeling towards the problem of how to economically and efficiently conduct the operation and simulation of urban rail transit network. We built a core simulation model mainly formed of topology infrastructure model of the network, simulation model for the process of train operation and the simulation model for the process of passengers’ travel in order to meet the need of the train operation and passengers’ travel. Having constructed the distributed simulation structure for the networked operation based on fixed distributed strategy, we proposed a simulation clock coordination mechanism based on key synchronous events, and developed a distributed simulation system for the networked operation of urban rail transit system. Taking the congestion situation for the passenger flow of Beijing’s subway and the confirmation for the passenger flow limitation scheme of the network coordination as the backgrounds, two conducted the applied research on the distributed simulation system for the operation of urban rail transit system.

Jiaping Feng, Xi Jiang, Feifan Jia, Chi Zhang

Automatic Train Control with Actuator Saturation Using Contraction Theory

Application of contraction theory provides a platform to analyze the exponential stability of nonlinear system. To effective compensate the time-varying parametric uncertainties exist in the longitudinal dynamics of the train, this paper proposes a contraction based saturated adaptive robust control for automatic train operation, which is subject to input limit of actuator. With consideration of actuator saturation, a recently developed robust modification is used to saturate the control input in each step, while the global stability is preserved. The resulting saturated adaptive robust control renders the transformed error enter the predefined region, furthermore, inside the predefined region, the contracting behaviour of closed-loop dynamics is regain and the tracking error exponentially converge to a residual set subsequently. The results of comparative experiments under different control strategies also verify the effectiveness of the proposed saturated adaptive robust control.

Yue Li

Linear Quadratic Optimal Control of Passenger Flow in Urban Rail Transfer Stations

In order to solve the problem of overload passenger flowing in urban rail transfer stations at peak hour, this paper proposes a passenger flow control model for transfer stations. To minimize the passenger density on platform, the passenger flow control model is built based on linear quadratic optimal control theory. And the optimal control passenger sequence flowing into platform is calculated during the control periods. Finally, taking Huixinxijienankou Station on lines 5 and 10 in Beijing subway as an example, the station simulation model using Anylogic software is established and used to verify the passenger flow control model. The simulation results show that the control model can reduce the passenger flow effectively on platform at peak hour and provides guidelines for boarding limit.

Huijuan Zhou, Qiang Zhang, Yanwei Feng, Yu Liu, Guorong Zheng

RUL Prediction for Bearings Based on Fault Diagnosis

In recent years remaining useful life of rolling bearings is paid much more attention. In this paper, the remaining useful life prediction based on fault diagnosis is proposed. Based on the real-time fault diagnosis results of the bearing, the remaining life is predicted and a set of bearing life expectancy prediction system is established by obtaining the vibration signal. In order to solve the problem that the whole life fault data is difficult to obtain, make full use of the bearing information contained in unlabeled data and take into account the advantages of each algorithm, the remaining useful life prediction of bearing is studied based on a semi supervised co-training method. The effectiveness and prediction accuracy of this method are demonstrated by a case study.

Dong Yan, Xiukun Wei

Two-Objective Optimization Reinforcement Learning Used in Single-Phase Rectifier Control

Regarding the single-phase rectifier control as a Markov Decision Process (MDP) with continuous state space and discrete action space and in the meantime, we introduced a new two-objective optimization reinforcement learning framework and proposed a genetic algorithm to train the learning agent in order to optimize power factor and output DC voltage. This article analyzed the convergence of our new algorithm and presented favorable performance of numerical simulation.

Ande Zhou, Bin Liu, Yunxin Fan, Libing Fan

Optimization Design and Research of LEACH Algorithm in Large Region of Rail Transportation

An improved LEACH algorithm is proposed to address the limitation of randomly selected cluster heads in an application environment with a large area of rail transportation. Through division, the number and selection of regional cluster heads are optimized to improve the robustness of the LEACH protocol in large areas of rail transportation. Simulation results show that the new algorithm exhibits significant improvement in terms of node survival number, data transmission, and network survival cycle compared with the LEACH algorithm, and thus, the lifetime of wireless sensor networks is prolonged.

Chongjun Liu, Kuangang Fan, Pingchuan Liu, Gaoxing Ding
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