Intelligent AC contactor with contacts for switching reactive compensation device

A novel intelligent switched capacitor AC contactor is proposed in this paper. This kind of intelligent AC contactor is developed by modifying the control circuit and the structure of a general AC contactor. It is especially designed to improve the power factor of a system through the reactive compensation of its switching capacitors. It adopts a novel approach, where the system's capacitors switch within a narrow domain around the voltage zero-crossing. This way the surge current is greatly reduced, leading to energy savings, low operating noise, high electrical span, and high operating frequency. We expect this new type of intelligent AC contactor to find broad applicability in power distribution systems, especially smart power grids.