Quality power

Both single-phase charging systems and three-phase charging systems would contain power electronic devices that as a side effect introduce waveform distortion and create power quality problems. Filtering devices used in conjunction with residential charging systems could be used to reduce harmonics and other power quality problems, but the cost of such filtering devices is currently quite high. 

Alternatively, the auxiliary power device can be some other RES with the appropriate equipment or a diesel engine, which can be obtained in various sizes and specifications. It is presumed that in a stand-alone system the requirements for power quality are not the same as that for a grid-connected consumer [43]. 

Power-monitoring software can be used to analyze energy use and power quality. It can identify load profiles to help with rate negotiation. If companies know their energy profiles, how and when they consume power, they can negotiate better rates for the type and amount of power they need. 

Suppression of harmonics so that the power quality is within the IEEE 519 harmonic limits requirements... 

A cooperative alliance of Kenetech Corporation, Pacific Gas and Electric Company, Niagara Mohawk Power Corporation, and EPRI has developed an advanced, utility-grade variable speed wind turbine that can deliver 300 kW. Commercially available and in widespread use, the turbine uses advanced power electronics to increase turbine efficiency, improve power quality, and lengthen turbine life. Future efforts are directed at developing turbines capable of individually producing 500—1000 kW for eventual deployment in a large-scale power role. 

What is power quality Power quality, as defined in this book, is a set of electrical boundaries that allows equipment to function in its intended manner without significant loss of performance or life expectancy. Conditions that provide satisfactory performance at the expense of life expectancy or vice versa are not acceptable. 

Chapter 9 Measuring and Solving Power Quality Problems... 

A simpler and perhaps more concise definition might state Power quality is a set of electrical boundaries that allows a piece of equipment to function in its intended manner without significant loss of performance or life expectancy. This definition embraces two things that we demand from an electrical device performance and life expectancy. Any power-related problem that compromises either attribute is a power quality concern. In light of this definition of power quality, this chapter provides an introduction to the more common power quality terms. Along with definitions of the terms, explanations are included in parentheses where necessary. This chapter also attempts to explain how power quality factors interact in an electrical system. 

Webster s New World Dictionary defines terminology as the the terms used in a specific science, art, etc. Understanding the terms used in any branch of science or humanities is basic to developing a sense of familiarity with the subject matter. The science of power quality is no exception. More commonly used power quality terms are defined and explained below ... 

Power quality is a simple term, yet it describes a multitude of issues that are found in any electrical power system and is a subjective term. The concept of good and bad power depends on the end user. If a piece of equipment functions satisfactorily,... 

The subject of power quality is one of cause and effect. Power quality is the cause, and the ability of the electrical equipment to function in the power quality environment is the effect. The ability of the equipment to perform in the installed environment is an indicator of its immunity. Figures 1.14 and 1.15 show power quality and equipment immunity in two forms. If the equipment immunity contour is within the power quality boundary, as shown in Figure 1.14, then problems can be expected. If the equipment immunity contour is outside the power quality boundary, then the equipment should function satisfactorily. The objective of any power quality study or solution is to ensure that the immunity contour is outside the boundaries of the power quality contour. Two methods for solving a power quality problem are to either make the power quality contour smaller so that it falls within the immunity contour or make the immunity contour larger than the power quality contour. 

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