Electric Power Engineering Research and Education

The proliferation of nonlinear loads such as power converters, fluorescent bulbs, and adjustable speed drives (ASDs) in the power distribution system gives rise to harmonic distortions in voltage and current waveforms. While drawing a fundamental current from the supply system, a nonlinear load injects non-sinusoidal currents back to the supply system. The distorted load current interacts with the system impedance and in turn distorts the utility’s supply voltage. As a result, other loads connected to the same distribution system end up drawing distorted currents as well. Significant voltage distortion increases the system losses and adversely affects the operation of end-user loads. In this chapter, the concept of power system harmonics is introduced and the approaches to analyze the distribution circuit in the presence of nonlinear loads are discussed. The power quality issues due to harmonic distortions and power system indices to quantify them are summarized as well. The voltage–current characteristics and the circuit models for several non-linear loads are discussed, followed by circuit modeling in the presence of harmonics. Several methods for harmonic power flow study are presented. A harmonic power flow study calculates active and reactive power flows, voltages, and currents at each node for each harmonic frequency. Several methods to mitigate power system harmonics using active and passive filters are also discussed.

Over the past few years research in the domain of data classification has shown that classifiers perform better when they are fed with only optimal features extracted from a raw data set. Concurrently, data classification using classifier fusion has reportedly produced significantly improved performance over separately working classifiers. Combiners again depend strongly on the careful selection of classifiers. This paper presents a novel attempt at bringing all these unto-now separate avenues together, to produce an optimal classification machine. For this purpose, a recently developed meta-heuristic algorithm, called Differential Harmony Search (DHS), has been used to select the optimal features, classifiers to which they are fed to and finally, the combiner used to fuse them. This classification tool so obtained is next used for power quality classification, where the Wavelet Transform (WT) is used to extract some useful features of the power system disturbance signal. Considering ten types of PQ disturbances, simulations have been carried out which show significantly improved and near optimal classification accuracy using the proposed methodology.

The usage of synchrophasors (synchronized phasors) is considered to be the most promising tool to monitor dynamics of modern electric power systems. Synchrophasors are measured by synchronized measurement units, such as Phasor Measurement Units (PMUs), providing high-speed measurements of voltage, current, and frequency. The PMU, as the most sophisticated time-synchronized tool, has been made possible by advancements in computer technology and availability of Global Positioning System (GPS) signals. Application of synchrophasor technology for wide-area measurement, monitoring, analysis and control of electric power systems can enhance its reliability, efficiency, and resilience. To achieve these benefits synchrophasor technology must be matched by advancements in other areas such as: data communications, instrument transformers accuracy, etc. One very important area is in developing methods and applications, i.e., software that uses the data provided by the PMUs. In this area utilities need huge help from academia. This is why Salt River Project (SRP) has established a joint research program with Arizona State University (ASU) and initiated several research projects. So far in many of them Prof. Heydt has been the Principal Investigator. In this chapter a summary of the results of a few such projects is given:

Wind generators are complex systems based on the latest aerodynamic, mechanical, and electrical designs incorporating coordinated sophisticated control systems. Wind generators have been erected in increasing numbers in the USA, the European Union, China, and other locations, especially smaller islands with no interconnections. European companies and US companies have lead developing technology.

The use of Geographical Information System (GIS) coordinates to formulate an alternate system matrix for the accommodation of Unscheduled Flows in wide-area power grids is presented. Wind variability impacts on Unscheduled Flows are also investigated in a standard test system using a Monte Carlo simulation. Power flow is executed using the PowerWorld^® commercial software package and governed by a Matlab^® script. Some concluding remarks and future scope are also presented in this chapter.

Transmission expansion planning (TEP) is a complex decision making process that requires comprehensive analysis to determine the time, location, and number of electric power transmission facilities that are needed in the future power grid. This chapter discusses the TEP problem in modern power systems, including the TEP process, available software tools, and mathematical models for TEP problems.

Distribution systems have evolved from manually operated radial systems to systems with increasing customer owned generation and many devices with embedded intelligence. Similarly, the amount of data that is available in real time from the system as well as smart meters at customer-end has seen exponential growth. The data can be used with advanced algorithms for real-time control of distribution systems to enhance reliability, efficiency, and quality. This chapter presents a historical overview of the progress of automation in distribution systems. Various contemporary issues that are relevant for modern distribution systems are discussed. Distribution Automation (DA) is defined and a detailed discussion of related functions is presented. This is followed by cost/benefit analysis of distribution automation functions with mapping of the functions to various expected benefits. Examples of expressions needed to compute benefits are provided. Finally, the chapter concludes with a view towards the future distribution systems and possible approaches for operating and controlling them.

I have known Prof. Jerry Heydt since the early 1970s as a contemporary colleague. I consider him not only a close and congenial friend but, more importantly, a mentor and inspiring colleague. I have learned a lot from my close association with him. Knowing him is a great asset in my professional as well as in my personal life. We have collaborated in all the three important domains of education, research, and outreach for over 40 years. In this chapter, I endeavor to cover the rich experiences of my close association with him in all these three areas that are the very essence of a successful academic professional. Though we now have both entered the stage in life that most would consider close to retirement, his Mantra has been that “Retirement is for quitters.” I whole-heartedly agree with that sentiment. Prof. Heydt not only keeps himself busy professionally but also continues to work very hard. I provide the details of my rich experiences with him in the following domains.

The purpose of this chapter is to highlight the great contributions of Professor Gerald T. Heydt in power engineering education. Dr. Heydt is a distinguished educator and researcher admired by power engineering educators and students around the world. Through teaching, research, textbook writing, and leadership in power engineering educational activities, Dr. Heydt has set a prominent example for many to follow. For his contributions in power engineering education, Dr. Heydt received the IEEE Outstanding Power Engineering Educator Award and the Edison Electric Institute Power Engineering Educator Award.

This chapter is concerned with the current and future shortage of the power engineering workforce faced by the power industry in the USA. In 2008, the Washington State University (WSU) Energy Program completed a regional labor market and workforce study of electric power employers. The study collected data regarding new hiring, anticipated retirements and replacements, hiring challenges, and workforce education needs. The study mirrored national predictions about the aging utility workforce, looming retirements, challenging population trends, and other factors that were predicted to create considerable labor and skill gaps in the electric power industry. It primarily focused on technical craft occupations: operators, mechanics, electricians, technicians, and line workers. The engineering workforce was not a focus of the original study.

Since that time, the electric power industry has continued to transform how it generates, transmits and distributes electric power through the application of advanced technologies and processes, and other Smart Grid innovations. At the same time, the deepest recession since the Great Depression contributed to delayed departures by retirement-eligible employees. Yet how those two factors affected the power industry and its workforce has not been well understood. The intent of this second study, sponsored by the WSU Energy Systems Innovation Center, was to investigate power engineering specifically.