The application of power factor correction capacitors to eliminate utility power factor penalties is generally motivated by economics. This paper will focus on the application of power factor correction capacitors to eliminate utility power factor penalties from the perspective of power quality. The end user is presented with a plethora of advantages. The advantages of applying power factor correction capacitors include: reduction of the electric utility bill; reduction of I~2R losses, and the concurrent heating in lines and transformers; increased voltage at the load; increased production and/or efficiency of operation; and reduction of current in the lines and transformers, which in turn, allows additional loads to be served without building new circuits. One of the most common causes of electrical transients is the switching of capacitor banks in power systems. The switching of capacitor banks is accompanied by a surge of current and voltage rises, which many solid-state motor controllers are quite sensitive to. In some cases, capacitor switching causes the voltage waveform to undergo oscillations and produce stray crossings of the time axis. This production of stray crossings is unacceptable for devices that require a precise number of zero time crossings for proper performance. This paper will define power factor, and include in detail what causes low power factor, and how to correct it. The importance of low power factor impacts on the electrical system will also be covered. The impacts on the electrical system will include effects on the utility bill, wire capacity, and heating in lines and transformers. A case study of the Merrirmack College distribution system, focusing on power factor issues, will be discussed. This description will include a capacitor bank, designed to increase the power factor to a desirable value and to eliminate the transients caused by the capacitor switching. There is a provision of data collection and analysis performed during this case study.
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