Power Quality VAR Compensation in Power Systems by R. Sastry Vedam and Mulukutla S. Sarma

 Power Quality VAR Compensation in Power Systems by R. Sastry Vedam and Mulukutla S. Sarma

Content : 

Chapter 1 Power Quality

Chapter 2 Static Var Compensators

Chapter 3 Control of Static Var Compensators

Chapter 4 Harmonics

Chapter 5 Utility Harmonic Regulations and Standards

Chapter 6 Harmonic Filters

Chapter 7 Computational Tools and Programs for the Design and Analysis of Static Var Compensators and Filters

Chapter 8 Monitoring Power Quality

Chapter 9 Reactors

Chapter 10 Capacitors

Chapter 11 Fast Fourier Transforms

Preface

In many countries the electricity supply industry has been deregulated. Though the designs of electricity markets vary, there are some common features. Generation, transmission, and distribution functions have been split up. There is competition in generation and distribution, whereas the situation in transmission everywhere approaches a monopoly. Further, the regulatory authorities ensure that no company providing power may overcharge customers and make huge profits. There are also regulations to help ensure the reliability and quality of power supply. The utilities must ensure a reasonable quality of supply, that is, without too many sags, swells, and high harmonic voltages affecting the performance of customer equipment. These changes have put considerable pressure on the utilities to become efficient and at the same time provide reliable supply without too many interruptions.

In addition to the above effects of the deregulation and creation of today’s electricity markets, utilities have to supply increased loads to the customers. There has been widespread use of power electronic equipment that generates harmonics. To meet these increased loads, utilities would like to strengthen the transmission system by building more interconnectors. It is rather difficult to obtain permission from the local authorities for new routes of transmission lines due to (a) the increase in built-up areas, (b) the need to retain good farm land, and (c) other aesthetic and environmental considerations. Hence, utilities have to find other technical solutions like static VAR compensators (SVCs), capacitors, and reactors for reactive compensation purposes. At the same time, utilities must ensure that their power quality is not affected due to harmonics generated by electronic equipment. In quite a few situations such as high-voltage DC transmission (HVDC), SVCs-suitable harmonic filters must be provided.

There is a realization by most governments that they must decrease the use of fossil fuels and increase the use of the other renewal energy sources—wind, solar, fuel cell, geothermal technologies, etc. These technologies also use power electronic devices to connect the generated power to the grid.

Use of FACTS (flexible AC transmission systems) devices, SVCs, universal power flow controllers, dynamic voltage regulators, etc., is increasing, and so are solid-state devices, mobile phones, color TV sets, personal computers, and fluorescent tubes. This, in turn, raises harmonic levels in the power system. All these create power quality problems.

Furthermore, to reduce labor costs for operation, and to increase reliability of supply, single-pole auto recloning is employed. Because 80% of the single-phase-toground faults are temporary due to lightning, etc., the power supply can be restored quickly by installing single-pole autoreclosing facilities.

Because transmission lines and interconnections are loaded to full capacity, any faults on the system or elsewhere cause reliability problems. In addition to these negatives, unbalanced distortion of three-phase voltages can occur if there are significant single-phase loads (e.g., traction loads) in an area. Hence, this reference book was undertaken to cover in a single volume all of these different topics: power quality; harmonics—their sources, analysis, measurement, and monitoring; harmonic filters and their design; harmonic standards; SVCs in main transmission systems, and SVCs for compensating traction loads to reduce flicker due to arc furnaces, that is, for load balancing, power factor improvement, and improving power system damping in general.