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This book presents select proceedings of Electric Power and Renewable Energy Conference 2020 (EPREC 2020). This book provides rigorous discussions, case studies, and recent developments in the emerging areas of the power system, especially, renewable energy conversion systems, distributed generations, microgrid, smart grid, HVDC & FACTS, power system protection, etc. The readers would be benefited in terms of enhancing their knowledge and skills in the domain areas. The book will be a valuable reference for beginners, researchers, and professionals interested in developments in the power system.

### Ground Fault Detection Using Pole Differential Current Measurement for 2-Terminal Bipolar HVDC Lines

Transmission line faults in HVDC systems result in sharp increase in the DC current. This increment in current should be interrupted as fast as possible to prevent damage of converter valves and resultant disturbances in the associated AC systems. For protection by communication-based schemes, there should be faster telecommunications between the rectifier/inverter stations. If not, this leads to delayed controller actions and subsequent damage to the system. Moreover, the reliability of these schemes is highly dependent on the communication channels. This paper proposes a protection algorithm for most frequent pole-to-ground faults using one-end current measurement and thereby be independent of communication delays. Current samples at the rectifier terminals are used to calculate the pole differential current at each station and compared with a threshold setting to detect the fault. The proposed technique is applied to a ±500 kV, 2-terminal bipolar HVDC system of 900 km line length. The test system is simulated in PSCAD/EMTDC software, and the protection scheme is implemented in MATLAB. The simulation results show a successful detection of faults created at different line lengths with variable fault resistances up to 500 Ω. The maximum detection time is less than 5 ms.

Ravi Shankar Tiwari, Om Hari Gupta, Vijay K. Sood

### A Review on Islanding Detection Schemes for DC Microgrids

Islanding detection plays a significant role in both AC and DC microgrids (MGs) protection. Its failure can lead to instability in the system. As a result, the load-side devices and consumers get affected. Many researchers have proposed various schemes to handle the failure of islanding detection in AC and DC MGs. But, AC MGs are well advanced and easy as compared to DC ones. Alternatively, DC MGs research is a challenging task because of the absence of standards, protection schemes, proper control strategy, and many more. It gains enormous attention among the researchers due to its better efficiency with less number of converters. Recent research focus is on fault detection, localization, islanding, and coordination of DC MGs. This paper presents an overview of various islanding detection schemes (IDSs), such as passive and active IDSs for DC MGs. A comparison between AC MGs IDSs and DC MGs IDSs is carried out to show the efficacy of DC MGs. Moreover, a detailed classification is carried out for DC MGs IDSs, and a rigorous discussion on each IDSs is presented with their advantages and disadvantages. The possible challenges of each DC MGs IDSs are discussed for conducting further research in this field.

Bhabani Kumari Choudhury, Premalata Jena

### Novel Fault Detection Scheme Using Stockwell Transform for Transmission Lines with Wind Power Penetration

In power sector, distributed generators have revamping behavior resulting several impacts over the system which need to be investigated. Protection equipments used in power systems are widely used and distributed all over the entire network and facilitating the utilities to enhance the system against various symmetrical and unsymmetrical faults; their identification and segregation is necessity. This proposed novel method of S-matrix obtained from signal features using Stockwell transform for fault determination along with wind power generation is implemented. This approach depends upon the thresholds and algorithm later detects the faults which are implemented over the IEEE 34-bus systems tested on MATLAB Simulink.

Nishant Saxena, Rachit Saxena, Krishna Murari

### Optimization of Load Distribution Between Distributed Generation Units of a Similar Technology Using Dynamic Programming

Increasing power demands coupled with the shortage of electricity supply, rising cost of energy, and power quality problems have encouraged utilities to look for better sources of power supply, considering technical, economic, and environmental benefits. The acceptance of distributed energy resources is based on the lower operating costs and easier deployment when compared with the fossil fuel-based generating units. This paper presents an approach for optimization of load distribution between several distributed energy resources. On the first stage, optimal sizing and placement of generation units for reducing total power losses and improving voltage profiles in a radial distribution network were determined. On the second stage, the problem of optimization of load distribution has been addressed using dynamic programming.

Illia Diahovchenko, Anastasiia Horbul

### Improvement of Voltage Regulation in an IEEE 9-Bus Radial Microgrid Feeder Using Regression Model

In this paper, an effort has been made to improve voltage regulation (VR) in a radial bus, typically used in a rural microgrid distribution network. As a case study example, an IEEE 9-bus radial feeder has been considered. The methodology uses a regression-based model that involves five input parameters for obtaining the voltage at a particular bus of the feeder. It has been seen that the addition of a suitable magnitude of leading reactive power at the last bus can improve the regulation. The object of this study is to analyze the impact of the magnitude of the injected reactive power that will improve the voltage regulation at the worst affected bus (the last bus), with voltage levels at other buses in acceptable limits. The study shows that although the injected VAR does help to improve the VR, the changes, however, are not very significant. Thus, a conclusion can be drawn that in IEEE 9-bus system, reactive compensation at the extreme bus is not the best solution to obtain appreciable voltage improvement in the system. The injection at other buses can be tried in seeking VR improvements

Yuvraj Praveen Soni, Eugene Fernandez

### Optimal Power Dispatch of Renewable Energy-Based Microgrid with AC/DC Constraints

Microgrids (MGs) give solutions for energy management in power systems. It is an important part of the energy system to have a local generation of power from renewable energy sources to meet power demands with high efficiency and minimum operating cost. Optimization architecture of MG for optimal dispatch is established in this paper considering thermal diesel generating units (DGs), wind power generation, and solar photovoltaic units (PVs) as renewable sources of energy and energy storage system (ESS). Considering the islanded operating mode of MG, the system modeling is done in IEEE modified 33-bus system. Injection of renewable energy and localized power generation allows grid operators to meet their energy needs without having to purchase power from the grid. The purpose of this paper is to optimize power allocation of the given system to reduce the cost of operation and have an efficient dispatch of power in MG taking into account renewable power generation and energy storage technology. AC/DC power flow network constraints with renewable and non-renewable energy systems are discussed for each case. A 24-hour time duration analysis is performed on the system, and the results are compared for both AC and DC optimal power flows.

Sunil Kumar, G. L. Pahuja

### An Overview of Implementation Issues of Smart Grid

The smart grid is an emerging area of power industry that is revolutionizing the existing grid by various means. Several key attributes like bidirectional communication, enhanced efficiency, reliability, and sustainability are prominent in the smart grid. The smart grid makes a difference in the generation, transmission, and distribution technologies with respect to the existing grid. However, the current state of the smart grid is still having a number of barriers that need to be addressed before deployment. This paper firstly analyzes the key differences between the smart grid and the existing grid on various notable dimensions. The paper finally ends by highlighting the practical issues related to the implementation aspects of the smart grid, which is essentially required to make the smart grid stable, responsive, and secure.

Mayank Srivastava

### A Performance Evaluation of SO2 Gas and SO2/CO2 Gas Mixture as Potential SF6 Gas Alternatives in Power Transmission and Distribution System

SO2 as unitary gas has comparable insulating properties. The calculated swarm parameter like drift velocity and effective ionization of binary gas mixture of SO2/CO2 also shows considerable proximity with insulation performance as observed in this study. The BOLSIG+ tool is used to calculate these properties for unitary gas like SO2, CO2, SF6, and N2 as well as a binary gas mixture like SF6/N2 and SO2/CO2. The calculated results are in close agreement with other reported values.

Akhilesh Kumar Pandey, Pushpendra Singh, Jitendra Kumar Singh, Shahnawaz Khan

### An Islanding Detection Methodology for SOFC-Based Static DG Using DWT

As the penetration of renewable-based power generation at a small scale into the distribution system is increasing, there are different challenges in terms of control, operation and protection of a microgrid. The detection of an islanding event—refers to a case of loss of utility grid—is one of the challenges. The usual requirement is to detect this event faster and accurately so as to enable control mechanism to further take care of distributed generation disconnection or mode change. This study presents a discrete wavelet transform-based islanding detection methodology. The rigorous MATLAB-based simulations are conducted for the performance investigation, and the results show that the proposed methodology is accurate and unaffected by the non-islanding events.

Salauddin Ansari, Om Hari Gupta, Manoj Tripathy

### A Novel Firing Angle-Based Power-Flow Model of TCSC

This paper studies the performance of firing angle-based power-flow model of the thyristor controlled series capacitor (TCSC) with the help of Newton–Raphson algorithm (NRA). In the presented work, the TCSC, which is a series flexible AC transmission systems (FACTS) device, is incorporated in a transmission line to vary its active power flow. The incorporation of TCSC has been carried out in all the lines of the bus system and its performance assessed. Corresponding to the obtained values of active power, the measure of firing angle of TCSC and its mode of operation has been determined using the NRA. The proposed TCSC model is implemented in the IEEE 14- and IEEE 300-bus systems. The line chosen to incorporate TCSC is on the basis of faster rate of convergence. The results validate the proposed model.

Palak, Pawan Yadav, Vedant Tiwari, Suman Bhowmick

### Impact of Responsive Demand Scheduling on Optimal Operation of Smart Reconfigurable Distribution System

In this work, a two-layer optimization framework to investigate the effect of responsive demand scheduling on distribution network in the presence of distribution feeder reconfiguration (DFR) is proposed. In the first layer, scheduling of responsive demand is carried out. For this purpose, two objectives: minimize customer energy payment and load variance of network is developed from perspective of customers and network operator respectively. These objectives are optimized both independently and jointly. In the second layer, the problem of DFR is solved with the modified load profile obtained from first layer to minimize energy losses. The joint optimization of customer energy payment and load variance of network in the first layer is formulated as a multi-objective model and solved using an augmented $$\epsilon$$ ϵ -constraint method, and the trade-off solution is obtained using fuzzy min–max satisfying criteria. The DFR problem in second layer is solved using genetic algorithm. The efficacy of the proposed two-layer framework is assessed on 33-bus distribution system.

Tanuj Rawat, K. R. Niazi, Nikhil Gupta, Sachin Sharma

### Optimal Sharing of Real Power Using Robust Controller in Multi-terminal DC Systems

In this study, a linear matrix inequality (LMI) optimization-based linear quadratic regulator control strategy proposes five terminal VSC-MTDC systems. The power demand at any terminals reflects in terms of undesired oscillations and sluggish power electronics equipments as well as its performance. The Result injects undesired oscillations in the grid and reduces power system stability. The proposed controller aims to the optimal distribution of real terminal power and terminal voltages through minimum oscillations in the presence of power demand variation. The proposed controller weight matrices are tuned, and controller gains are calculated using LMI tool framework. The stability convergence of the proposed controller is analyzed using Lyapunov theorem. The performance and its effectiveness of the proposed strategy investigate in terms of time response characteristics and its applicability. The MATLAB© simulations are demonstrated on five terminal VSC-MTDC system to illustrate the effectiveness of the linear quadratic regulator based on the strategic control.

Himanshu Singh, Suyash Singh, Sheetla Prasad, Lokesh Garg

### Voltage Ripple-Based Islanding Technique on Modified IEEE-13 Bus Test Feeder for Photovoltaic Inverter

Islanding is the major threat of integrating distributed generation to the primary grid which takes place once the primary grid is detached from the distribution generation while the local load continues to energize by the distribution generation. It can introduce severe and perilous security conditions if islanding is not identified immediately. From this article, we present a unique and proficient passive islanding identification strategy on the IEEE-13 bus feeder connected to a photovoltaic-based inverter. In this method, the ripple present in inverter output voltage at the point of common coupling (PCC) is inspected for changes in the time domain analysis. Now, once the ripple present in the inverter outputs voltage more than the predefined threshold limit for a particular duration of time, then islanding is reported. Many different non-islanding and islanding cases are widely tested and investigated during a comprehensive set of a mode of operation. The technique showed zero non-detection zones (NDZ), and it was found that all types of islanding cases could be detected 210 ms of the permitted delayed time.

Salauddin Ansari, Om Hari Gupta

### Overview of Electric Vehicle: Opportunities and Challenges with Smart Grid

Electric vehicle (EV) has become the green transportation tool for the twenty-first century due to rise in pollution level all across the world. Due to environmental concerns and growing price of gasoline and other fuels required for transportation, there is a need of EV which will curb the emission of harmful pollutants in the atmosphere. Therefore, the automobile industries have started to take necessary steps for the same, thus giving rise to EV in the society. EV is a highly researchable topic and has gained immense attention in past few years. This paper briefly introduces the electric vehicle including its types, components, and the concerned economics. It also discusses about the interaction of EV with the grid and the optimization objectives that the EV industry is focusing upon. This paper also states the challenges that the optimization techniques might face while integrating EV with the grid.

Atma Ram Gupta, Rishabh Gupta, Saurav, Aditya Tiwari, Ranjana Purohit

### HVDC Transmission Topology and Control Analysis

This paper presents the study of various configurations in HVDC transmission, converter topologies, and its control analysis. The HVDC system configuration and converter topologies play significant roles in terms of economy, efficiency, and reliability in operation together with existing AC transmission networks. Due to the absence of DC circuit breakers in 2-terminal HVDC transmission, any normal and abnormal disturbances are taken care of by its control arrangement. The rectifier and inverters converting stations are crucial parts of DC transmission system provided with current control (CC), voltage control, extinction angle control (CEA), voltage-dependent current control (VDCOL), and many more control arrangements for stable operation during steady-state and transient disturbances. A mono-polar HVDC transmission system is simulated in PSCAD/EMTDC, and the results are transported into MATLAB software to analyze the control under steady-state and transient disturbance may occur in associated with AC–DC systems.

Ravi Shankar Tiwari

### Modeling and Simulation of Photovoltaic Solar Cell Microgrid

By the reason for the significant increase in energy requirements and involvement about global temperature change, continuously distributed generation (DG) property like solar energy, fuel cells, and wind energy. Civilization draining the traditional resources of energy faster and faster. To meet the remaining interest, alternative energy resources like solar energy are required. In this case, it has the features of worry-free, pollution-free, clean, unlimited, and free. The large-scale implementation of DG in homes involves generating energy from PV cells in each residence. This mechanism is particularly suitable for rural electrification designs with relatively low load requirements and still high connection costs. The article discusses the application of an island or grid-connected microgrid design by a solar system installed in a residence. By the use of Simulink different power, voltage and current levels, such as PV models can be fully explained. Simulink is completed at the end of the grid and the load in island conditions as well as non-island conditions.

Munna Kumar, Kanak Bhengra, Jitendra Kumar

### Effect of Electrical Vehicles Charging on Distribution System with Distributed Generation

Electric Vehicles are future of the automobile industry. The electrical storage devices are backbone of these vehicles. These batteries are to be charged directly from an outlet. Normally these outlets draw power from the distribution network. These new electrical loadings have an impact on the distribution grid. These impacts can be studied and examined in terms of power quality. This may cause potential transformer overloads, feeder and undue circuit faults. An analysis from these leading has been presented in this work. Moreover, it has been found that the inclusion of the Distributed generation (DG) units can easily reduce the adverse impact of Electric Vehicle Charging (EVC) charging on distribution system.

Nilesh Bhut, Bhargav Vyas

### Renewable Power Generation Using Asynchronous Generator: A Review

Wind energy is the form of sun energy. Flow of wind is not uniform all time. For conversion of wind energy into electrical energy synchronous generator were used. Synchronous generator used for the constant speed of power generation. So using synchronous generator for irregular wind energy conversion in electrical energy is not efficient. Due to such disadvantages of fixed speed generator, recent days variable speed generator using called doubly fed induction generators. This asynchronous generator has many advantages over fixed speed generator system. An asynchronous based turbine has a capacity to convert the wind energy into maximum electrical energy with changing and customizable speed. It is also having the capacity to control active and reactive power with the help of power electronics converter. When operating the doubly fed induction generator, generating system controlling and handling the plant for smooth and efficient operation is challenging task. Many control strategy were proposed by the researchers discuss in this chapter. This chapter presents an outline and a deep review of recent decades on the various issues related to infiltration of doubly fed Induction generator in wing generation system. Also discuss various problem associated in the proposed techniques and what the improvement required for future work.

Nagendra Singh, Ritesh Tirole, Shekh Kulsum Almas, Dimpy Sood

### Estimation of the Monthly Standard Diffuse and Universal Solar Eradiation for the City Varanasi, Uttar Pradesh, India

Solar radiation data is important for supposing power capacity that can be set up from photovoltaic unit. Solar radiation tumbling on the earth’s exterior is consistent by an equipment called a total radiometer. This paper describes the process for the development of monthly standard universal and diffused radiation for the city Varanasi in Uttar Pradesh, India. It can be located at Longitude: 82.9738° E and Latitude: 25.3076° N at an elevation of 81 meters. The Gopinathan model has been used for the calculation of values of the monthly standard universal cosmic radiation. Gupta and Kreith’s models have been used for estimating the values of monthly standard diffuse cosmic radiation. The calculated data has been analyzed and the result has been simulated through MATLAB.

Munna Kumar, Nalini Singh, Jitendra Kumar

### Evaluation of Residual Inductance of the Impulse Generator for the Generation of Lightning Impulse Voltage

This paper presents an optimization method for the design and analysis of impulse generators according to the requirements of the international standard IEC 60060-1. An optimization algorithm has been developed to calculate the residual inductance in the impulse generator circuit. The optimization approach can calculate the residual inductance which is practically present in the circuit and the characteristics of the generated waveform. Calculation of inductance which is present in the system of an impulse generator, by knowing the output waveform of impulse is attempted. In this study the inductance value changing from zero to some finite value is identified corresponds to the peak overshoot of the impulse output. When inductance is equal to zero, an exact waveform of impulse is observed, and when there is residual inductance (Ls) then according to the value of inductance (Ls) there is the change in the front time as well as in the overshoot. Those changes are needed to consider for a proper design of an impulse generator.

Nidhi Chandrakar, Chadaram Chandra Sekhar, K. Chandrasekaran

### Optimal Placement of PMUs for Kerala and Tamil Nadu State Level Regional Indian Power Grid

This paper presents a novel methodology for finding the placement of optimal locations for phasor measurement units (PMUs) in a power system. Accordingly, various techniques are presented in favor of the optimal placement of the Phasor Measurement Unit (PMU). In this paper good method is used to reduce the minimal expenditure of setting up as well as gives the whole observability of power system by using the Genetic algorithm. The idea is to facilitate the system in total observability and finding the minimum number of optimal locations to place PMUs. The recommended technique is implemented on one IEEE 14 test system with a practical system of 104-bus Tamil Nadu state regional power grid and 31-bus Kerala state regional power grid. Results of the optimal location of PMUs were presented.

Chadaram Chandra Sekhar, P. Suresh Babu

### Study of Phasor Measurement Unit and Its Applications

Synchrophasors are the measuring elements in which time is synchronized. In this electrical waveforms are represented by both the magnitude and phase angle. The Phasor Measurement Unit (PMU) is fast time-stamped equipment as it provides synchronized and accurate data. It measures voltage, frequency, current phasors, temperature and vibration for all the buses of the system. In the past decades many literatures are presented about the application of PMU. This paper presents a brief review of Wide-Area Monitoring Systems (WAMSs), PMUs, communication and data quality required for the utilization of PMU application in power distribution system as data quality and communication are the important parts of synchrophasor technology.

### Optimal Placement of Electric Vehicle Charging Stations Using JAYA Algorithm

In this twenty-first century, it has witnessed that humans highly depend on non-renewable fuel sources, especially on transportation and generation of power. This dependency leads to an increase in oil prices because of the depletion of fossil fuels. Rise in greenhouse gas emission which is due to the burning of fossil fuels leads to global warming. To tackle the depletion of fossil fuels and environmental things related to greenhouse gases is the prime reasons for archetype from common vehicles to electric vehicles (EVs). Due to the booming number of EVs is a big menace to the distribution network. Charging of EV results in an increase in peak demand, as a result, it affects the continuous performance of the distribution sector. The electric charging station has to place in an appropriate location so that curtailment costs of installation and operating charging station (CS) and minimize power grid loss. JAYA algorithm is used to find an optimal solution of CS.

Ajit Kumar Mohanty, P. Suresh Babu

### PSO Based Optimal Reactive Power Dispatch for the Enrichment of Power System Performance

This paper proposes an Optimal Reactive Power Dispatch (ORPD) using Particle Swarm Optimization (PSO). ORPD, which is a section of optimal power flow, is considered as an essential optimization enigma in the sector of electrical engineering. With the help of ORPD, the operators have control over the voltage limits to retrench the true power losses in transmission lines. Formulation of ORPD is performed by considering the output voltages of generators, tap changing transformers and switchable capacitor devices. PSO is a well familiar population centered optimization system. This procedure is well-designed to the IEEE14 and 30 bus systems by considering reduction of true power loss. This scheme performance is improved with PSO, and the losses are comparatively low with traditional methods.

K. Manasvi, B. Venkateswararao, Ramesh Devarapalli, Upendra Prasad

### Design of Adaptive Distance Relay for Transmission Line Protection with Wind Power Integration

Whenever a distance protection is implemented to a system where renewable penetration exists, there is a chance that the distance relay may mal-operate based on the penetration level. So there is a need for the relay to adjust its characteristics according to the changes in the environment. This process of self-adjustment of its characteristics is called adaptability. A wind integrated system is simulated in PSCAD/EMTDC software, and the data is collected for line to ground (LG) internal as well as external faults for different wind generators (WGs) configurations. From the collected data, quadrilateral settings are found for different wind configurations. Then an adaptive logic is proposed such that out of all the possible quadrilateral characteristics, suitable one is assigned to the relay as per the number of WGs in service. Finally, the adaptive logic is verified under the simulation environment.

Venkata Rao Nikhil Garlapati, Sujo Palamoottil George, Ashok Sankar

### Superimposed Components Based Directional Relaying During Power Swing

Fault directional estimation (FDE) is very difficult during power swing period (PSP) due to variation of lower frequency components with fundamental frequency components. In this paper, for directional estimation of symmetrical as well as unsymmetrical faults during PSP, an FDE algorithm is proposed which consists of two algorithms. This FDE is dependent on angle between superimposed positive sequence (PS) and superimposed negative sequence (NS) components of voltage and current. The feasibility is high because of local-end relay data is utilized for execution of proposed scheme. The comparative study proves the superiority of proposed FDE over existing method. PSCAD platform is used to implement the 400 kV, 50 Hz system.

Shashi Bhushan Chandel, Lakshman Saroj, Kumar Harshavardhana, Himanshu Shekhar, Jitendra Kumar

### Energy Audit of Hybrid (Grid, Solar Rooftop Photovoltaic System and Diesel Generator) Electric Power Supply System: A Case Study of Commercial Building

World’s energy scenario is changing day by day, and developed countries are now focusing on 100% renewable generation. In developing country like India, increase in energy demand due to population growth and scaring of fossil fuels is taking place simultaneously. Government is making energy audits obligatory for using energy efficiently. India is focusing on reduction of oil/gas imports and lowering CO2 emissions which could be possible through the integration of renewable energy sources with existing conventional energy sources in the form of hybrid system. Despite of the advantages of hybrid system, it has some severe disadvantages. To address such issues, this research paper focuses on improving energy efficiency and finding areas of energy conservation in hybrid electric power supply system of a commercial building through energy audit. In our study, energy conservation is measured in the areas—electricity bills, voltage profile, harmonics profile, transformer loading and efficiency, diesel generator (DG) set, and solar rooftop photovoltaic system (RPVS).

Abhishek Pratap Singh, Aditya Singhal, Akanksha Athaya, Saurabh Kumar Rajput, Laxmi Srivastava, Vikas Sharma

### A Comparative Analysis of EVs Scheduling Strategies to Accomplish Valley Filling

This work aims to compare the effect of different electric vehicles (EVs) charging strategies designed to directly/indirectly shift EVs charging to valley periods on distribution grid load curve. Toward this goal, firstly, EVs charging profile is obtained under four strategies, namely minimum load variations model (MLVM), maximum load factor model (MLFM), valley search charging model (VSCM) and minimum charging cost model (MCCM), respectively. Thereafter, the effect of these charging strategies on average load, valley load, peak load, peak-valley difference and load factor of grid demand profile for different EV penetration is investigated. In addition, the effect on charging cost of EVs is also compared to these charging strategies.

Tanuj Rawat, K. R. Niazi, Nikhil Gupta, Sachin Sharma

### Islanding Detection Through Mean of Superimposed Voltage

In a microgrid, unintentional islanding is a threat to its security and stability. Islanding detection within pre-specified operating time is required. In this paper, a new technique MSPV of islanding detection is presented for distribution system which is based on superimposed voltage component. The proposed technique is fast and effectively distinguishes between islanding and different non-islanding situations even in 0% active power mismatch. Microgrid considered for the testing of islanding technique is simulated in MATLAB R2016a.

Kanak Bhengra, Munna Kumar, Jitendra Kumar

### Application of Admittance-Based Relaying Scheme Under Dynamic Shunt Compensation

With abrupt change in reactive power, demand in the system may lead to unhealthy voltage profile. To maintain the flat-voltage profile, static var compensators (SVCs) are mainly used. SVC controls voltage level by regulating the reactive power in the system. Introduction of SVC in the grid may lead to mal-operation of conventional relaying schemes for transmission line (TL) protection due to dynamic impedance variation of SVC during faulty condition. An existing differential admittance-based method is discussed and its application under the dynamic shunt compensation is obtained in this paper for different types of fault with different fault locations, inception angles, evolving fault, cross-country fault, and high resistance fault cases.

Jai Prakash Sharma, Shaili Shaw, Om Hari Gupta

### Wind Potential Assessment for Micropower Generation in Tropical Wet Climate of India

In this paper, wind potential assessment of a wind site of Indian state of Goa under warm humid climatic zone is proposed using statistical distribution functions. Weibull and Rayleigh models were used for the statistical analysis of wind speed using typical meteorological year (TMY) data and wind rose diagram was plotted to study the wind direction and velocity. The results obtained were promising in terms of wind power density and Raleigh model best suits for Goa wind site.

Santoshkumar Hampannavar, K. N. Patil, Swapna Manasani, R. Yaragatti Udaykumar, Rajashekar P. Mandi, C. Nandakumar

### Analysis of a Grid-Connected PV System Located in Educational Institution

In this article, an attempt has been made to examine the performance of an on-grid PV system located in an educational institution. The considered 56.7 kW PV system is installed over the Block-B1 of Shri Ramswaroop Memorial University (SRMU), Barabanki, Uttar Pradesh, India. The annual electricity yield and the payback period of the installed rooftop PV system has been calculated for reasserting the financial viability of the project. In addition, the comparison between real and approximated energy generation has also been analyzed. The impact of the subsidy on the payback period and the environmental benefits of the project have also been assessed.

Sunil Kumar Singh, Shikha Singh, Yashwant Singh

### Reduction in Bill Using Time of Usage Pricing in a Smart Grid

In today’s scenario, the Internet has dominated almost all domains. It led to revolutionary advancements in the existing technology by conceptualizing the ordinary power grid into a smart grid. Use of smart meters, sensors and other gadgets in the smart grid has made the existing cyber-physical system more resilient and efficient than the existing one. By the aid of the Internet, the components of the smart grid are connected to the same server. This paper emphasizes the importance of communication between the elements of the grid. A successful communication system allows the transfer of information and energy between the components of the grid. Components like wireless sensor networks (WSN) are useful for such networks. Along with an energy management unit, they can control the load demand of a consumer. The load demand is smartly shifted from peak hours to off-peak hours, following the concept of time of usage (TOU) pricing. Due to this shift in demand, the user has to pay a lesser amount for energy. This paper presents a unique approach based on devices which are easy to access. A case study is presented wherein data is transmitted via communication established between devices. The WSN and EMU smartly adjust the load in off-peak durations. A drop in the bill of the user is seen. This can be further extended for industries and other power system networks.

Saurabh Pranjale, Tharun Balaji, Soumya Mudgal, Syed Aamir Ahmed, Praveen K. Gupta, Neeraj K. Singh, Vasundhara Mahajan

### Congestion Management Based on Real Power Rescheduling Using Moth Flame Optimization

Congestion in transmission corridors is a major threat for power system operation. Proper and efficient congestion management initiatives must be adopted to mitigate congestion. This paper has chosen generator rescheduling strategy to manage the congestion. A technique of generator selection based on generator sensitivity factor has been introduced to identify the best generators for the real power rescheduling process. Further, a heuristic method named moth–flame optimization has been used to minimize the cost of real power rescheduling involved in congestion management. 39-bus test system based on the New England framework has been taken for validation of the proposed congestion management philosophy. The proposed strategy has been collated with the performance of other congestion management heuristic techniques and has proved to be efficient and robust.

Kaushik Paul, Niranjan Kumar, Debolina Hati, Anumeha

### Transmission Line Outage Estimation Through Bus Current Comparison Utilizing Current Phasor of PMU

In this study, a new methodology for transmission line outage estimation (TLOE) is presented. The proposed model is fundamentally based on the current phasors of phasor measurement units (PMUs) rather than voltage phasors which are used in most of the existing literatures. In this proposed algorithm, the simulated bus currents (SBCs) for various line outage cases (OCs) are saved in advance. As soon as the actual outage happens, measured bus currents (MBCs) from PMUs are compared with the previously stored SBCs using L-2 minimization technique. The estimation rate of the proposed algorithm is compared with different existing methods, and the simulation results are analyzed. Performance of the proposed methodology is tested on IEEE 5-, 14-, 57-bus, and DVC 38-bus Indian practical systems through MATLAB simulation. The obtained results reveal the applicability and feasibility of the proposed scheme for practical implementation.

Mehebub Alam, Shubhrajyoti Kundu, Siddhartha Sankar Thakur, Sumit Banerjee

### Analysis of the Impacts on Power Flow After Introducing Renewable Energy Source in a Power System with HVDC Line

In the power generation sector, renewable energy sources are getting popular with technological advancement and power engineers are trying to increase the power transmission capacity of a power system day by day. In an interconnected grid, both objectives can be achieved by installing a high voltage direct current (HVDC) transmission line and a wind power plant. Although the HVDC transmission system is costlier than AC transmission system, power transfer is easy and efficient. Wind power can create a problem because of the sizeable reactive power consumption of these machines, so both can hamper the stability of the power system if it is not designed correctly. For a stable power system, prior knowledge needed to design and to plan. This paper presents power flow analysis on Western Systems Coordinating Council (WSCC)-9 bus, three machine power systems without and with integrating wind farm and HVDC line. Power system analysis toolbox (PSAT) has been used for system design and simulation. After power flow analysis by using Newton–Raphson method changes in voltage magnitude, voltage angle, real and reactive power in various buses has been measured. Finally, a comparative study has shown that it is advantageous to add an HVDC link and wind farm together in a power system for better power flow efficiency and stability.

Md. Mehedi Hasan Tanim, Md. Feroz Ali, Md. Asaduzzaman Shobug, A. A. Mamun

### Techno-economic Assessments of Green Hybrid Microgrid

For the electrification of rural communities, the off-grid hybrid system is a more authentic and viable solution. The primary focus of this investigation is to propose an optimal solution for power generation for a medical hospital in rural villages in Nigeria. Different cases are studied and evaluated based on the Total Net Present Value (N.P.V.) and Cost of Energy (C.O.E.). The analysis was also carried out to find the electrical power production and environmental pollutants of different components. This paper presents the estimation of the hybrid system for electricity production as compared to a stand-alone system like a diesel generator (D.G.).

Sumit Sharma, Yog Raj Sood, Ankur Maheshwari

### Reduced the Fuel Cost by Using Renewable Energy-Based DG in Pool Electricity Market

Integration of renewable sources in power utilities is gaining importance all over the world. In a competitive system, it is important to consider the linearization of the energy segment, increasing share of renewable energy sources, and the impact of clean energy on system performance. In this paper, the wind-based and PV-based DG has been used for the minimization of fuel cost of convectional generators. A mixed integer nonlinear approach used for solved the problems and finds the optimal allocation of DG in the power network. Saving the fuel cost of convection generator (CG) with including the DG cost with different case will also considered. The results obtained with two different loads (constant and ZIP) and find flowing parameters: real and reactive nodal price, saved fuel cost, optimal location of DG and size of DG. The approached has been applied to IEEE-24 bus.

Manish Kumar, Ashwani Kumar, K. S. Sandhu

### Congestion Management in Power System—A Review

Power system deregulation created a significant impact in power system network. Though power system deregulation has advantage, it adversely affects the network congestion. Congestion mainly occurs due to failure of transmission utility to transmit the power based on the load demand. So, there is a need of congestion management techniques. Different congestion management techniques are reviewed in this paper which includes generator rescheduling, load shedding, nodal pricing technique, optimal location of diesel generator and some of the cost-free algorithms genetic algorithm, particle swarm optimization, shuffled frog algorithm, mixed integer nonlinear programming, and approaches corresponding to fuzzy logic. This paper reviews the publications of various works to evaluate the importance of every technique in mitigating congestion of transmission network.

Shaik Riyaz, Ramanaiah Upputuri, Niranjan Kumar

### Voltage Constrained Reactive Power Planning by Ameliorated HHO Technique

The demand for electrical power is continuously increasing which may lead to voltage depression in buses or excessive reactive power flow in branches. Solution of voltage constrained reactive power planning (VCRPP) problem aims to optimize objective function like transmission loss, operating cost, and betterment of magnitude of voltage by optimal adjustment of controlling parameters. In present work, Ameliorated Harris hawks optimization (AHHO) and Harris hawks optimization (HHO) algorithm have been applied for the solution of VCRPP problem of power system. Ameliorated Harris hawks optimization procedure improves searching process of the pray. The proposed approach has been tested and examined under different reactive loading conditions. The efficacy of the suggested method is demonstrated from the numerical simulations and justified by comparison with other evolutionary techniques for optimization.

G. Swetha Shekarappa, Sheila Mahapatra, Saurav Raj

### Performance Evaluation of Solar PV Array Under Various Partial Shading Conditions

The total installed capacity (TIC) of power generation in India is approx. 370 GW out of which the contribution of non-fossil fuel-based generation is nearly 22% (77.5 GW) and solar radiation-based generation accounts for TIC 8% (29.7GW). The United Nations Framework Convention on Climate Change (UNFCCC) dealing with greenhouse mitigations sets a standard to contain an increase in global temperature to 2 °C in this century. The participant member nations of Paris agreement 2015 agreed on “intended nationally determined contribution” (INDC) to reduce carbon emission. India’s INDC in the power sector is to achieve 175 GW through renewable energy by the year 2022. Considering these targets, India has put special focus on solar power generation with a target of 100 GW. In this analysis, a very important issue of partial shading and consequent non-uniformity of solar irradiance under various types of PSC is investigated. The series–parallel (SP) PV array topology is implemented on hardware platform. And results are being computed respectively.

Karni Pratap Palawat, Vinod K. Yadav, R. L. Meena

### Environmental Impacts from the System of Solar Energy

The technology associated with solar energy provides a cleanest, domestic, and inexhaustible renewable source of energy and its important necessities for renewable energy source in future span. System of solar energy (i.e., solar panel photovoltaics, solar thermal, etc.) that influences benefit of the environment in contrast to the traditional power sources (i.e., coal, petroleum, firewood, straw, etc.) However, it is recognized that the solar-based technological systems have some minor bad affects on the environment throughout the generation and application. This paper summarizes and discusses the effect of waste material of different systems of solar energy in the environment.

Mukesh Kumar Nag, Parmanand Kumar, Mani Kant Paswan

### Impact of DGs in Competitive Deregulated Environment for Congestion Management

Among the important responsibilities of system operator (SO) falls congestion management, which is to make sure that the power network is running within its limits which are thermal limit, voltage limit and stability limit. Considering the recent scenario of competition in the electric market, it is utmost necessary for the electricity providers to operate in such a way so that it makes better application of the existing transmission services in by maintaining the system constraints such as stability, reliability, and security of the supplied power. In the present paper, the application of DGs like wind and solar plant has been simulated and its impact in competitive deregulated environment has been studied.

Dipu Sarkar, Kabita Kumari, Rupali Brahmachary

### Co-optimal PMU Placement for Complete Monitoring of Distributed Generations Installed System

Considering the substantial amount of advantageous side of distributed generations (DG), power system operators are opting it as efficient generations option to meet up the today’s huge power demand. This paper proposes a novel technique for placement of PMUs co-optimally for complete power system monitoring when distributed generations (DG) are installed in the system. Graph theory-based intellectual search technique has been used to identify the further locations of PMU optimally to achieve complete observability. This method is applied on IEEE standard test systems—14 bus as the first test case and 30 bus system as the second test case to test the usefulness of it. The proposed technique is simple and straightforward. The result shows better redundant measurement percentage.

Anik Tahabilder, A. A. Mamun, N. Rahman, Pronob K. Ghosh

### A Comprehensive Review of Remote and Passive IDMs of Utility Grid Integrated MG System—Part I

In this literature, different islanding and their detection techniques are overviewed of the power system network consisting of distribution system along with distributed generator (DG). Penetration of renewable energy utilization and DG is increasing continuously. Islanding detection methods (IDMs) are divided as remote and local methods. Remote methods are based on communication while local methods are again categorized into three types: active, passive and hybrid methods. Active methods are based on direct interaction with the power system operation via perturbation, and passive methods are based on the utilization of local parameters while hybrid methods are the amalgamation of active and passive. Remote and passive IDMs for DG are described and analysed as per detection time, advantage, disadvantage, non-detection zone (NDZ) and power quality issues. Paper will give the broad idea for selecting the better one of IDMs.

Ravikant Shastri, Akshit Samadhiya, Kumari Namrata

### Optimal Share of DG and DSTATCOM in Distribution Network Using Firefly Algorithm

Integration of new devices makes distribution system (DS) more resilient and stronger in value chain. Optimally placed DG and DSTATCOM (DGDST) play a vital role to provide good quality of electrical supply to customers with increased reliability of the system. The losses occurring in DS influence the other section of value chain like transmission and generators, since we cannot store the electricity, so it should be utilized properly under several quality and reliable constraints. Due to large number of end users DS suffers with voltage drop, which can collapse the whole network. The power is being wasted in terms of heat and other losses. Large number of connected equipment and transmission lines increases the R/X ratio, which further degrades the efficiency of DS. Two important parameter power loss minimization and voltage compensation gives advantage to distribution system to operate smoothly in normal and faulty situation, so proposed paper apply a meta-heuristic firefly optimization algorithm technique applied to balanced radial distribution system (BRDS) IEEE-33 to investigate the optimal position and capacity of DGDST in two scenario single and multiple allocation simultaneously with weighted objective function under different cases considering all necessary equality and inequality constraints to avoid reverse power flow in DS. The results analysis presents the efficacy of proposed algorithm meticulously.

Jitendra Singh Bhadoriya, Atma Ram Gupta

### A Comprehensive Review of Conventional and Computational Islanding Diagnosis of Distributed Generator in Distribution Network

Sustainable energy generation methods are considered extremely beneficial for resolving future energy and environmental issues. Distributed generation (DG) is one such methodology to utilize renewable resources. Grid integration with various types of distributed sources such as wind, hydro, PV etc. can enhance energy efficiency and solve energy crisis problems. Distributed generators may work under both grid-connected and islanding modes. Islanding mode suffers certain challenges. Swift and precise islanding detection is key for the successful operation of distributed generators in distributed network. Various islanding techniques based upon passive, communication, active and hybrid have been put forward. Despite that each methodology has certain defects which may cause erroneous islanding diagnosis. These days’ intelligent methodologies because of their robust and flexible behavior in dealing with the complex non-linear system are a viable alternative which can resolve this issue. This paper presents comparative overview of a comprehensive analysis of conventional and computational intelligent techniques employed for islanding diagnosis of DG.

Akshat Kumar, Shaik Riyaz, R. N. Mahanty

### Economic Power Wheeling Using MW-MILE Method Through Gravitational Search Algorithm

The deregulation has brought many vital fundamental alterations in the electric power industry. Previously the vertically integrated structure of power system providing the three services generation, transmission, and distribution by a single party. After deregulation, the three service sectors may be operated (provided) by different companies or parties. As such the power can be generated by a company, it could be sold to any other company for distribution at load centers and it may be transmitted by a third party from the generation point of a selling point (load center/buyer), i.e., power wheeling from the generation point to the distribution point (buyer). In this paper, it is proposed to consider the economic power wheeling from the generation point to the distribution point through Gravitational Search Algorithm (GSA) based on the concept of MW-Mile method under two operating conditions with and without transmission line power limit. The method has been applied to a four-grid power system. The result of GSA method is compared with the result obtained by Particle Swarm Optimization (PSO) method. It has been shown that the computational time of GSA is lower than that of PSO which makes the performance of GSA superior than PSO for the proposed approach..

Anumeha, Kaushik Paul, Pratul Arvind, K. B. Yadav, Jayendra Kumar

### Materials and Methods for Performance Enhancement of Perovskite Photovoltaic Solar Cells: A Review

The continuous performance enhancement shown by perovskite photovoltaic cells in comparatively lesser time has made them to shine like a star among other photovoltaic solar cells. This paper elaborates on the principles, birth, research progressed and current status of perovskite solar cells. In addition, various fabrication methods of perovskite films and their performance behaviour are also briefed. This review also discusses future aspects and challenges being faced by perovskites.

Divya Sharma, Rajesh Mehra, Balwinder Raj