Report on automated capacitor switching (for power factor correction)

Abstract

The application of capacitors to distribution lines in order to correct power factor at peak loading conditions often result in leading power factors under light load conditions. The leading VArs, under light load conditions, result in added amperage in distribution lines. The author investigates the magnitude of the resistance losses, their cost, and a way of automatically controlling these losses. A method is proposed for determining the savings that could be obtained by automatically switching capacitors to minimize reactive volt amps that flow in distribution lines. It does not appear that small rural substations are good candidates for automatic capacitor switching. Larger substations (over 4000 kW average) that have significant reactive load do appear to be good candidates.<>