Capacitor application considerations-Utility/user interface

The continuously increasing use of power capacitors throughout utility and industrial paper systems has resulted in an increased awareness level of the application considerations associated with capacitor switching and harmonics. The author reviews these topics from a system point of view, emphasizing the system interaction effects and the means that can be used to minimize this interaction. It is noted that the switching of a capacitor bank can cause transient overvoltage concerns at other points in the system under certain conditions. A number of methods are discussed for reducing these transients, including closing and opening resistors, controlled closing, staggered closing, reactors, and surge arresters. Capacitor banks throughout the system can influence the distortion level that occurs due to a harmonic source. That effect can be minimized by using filter capacitor banks in the plant at the medium or low voltage buses which would be at or near the source of the harmonics.<>