Energy optimization control strategy for unified power quality conditioner

FEI Ping-ping1, JIANG Quan-yuan1, YAN Yu-ting2

(1. College of Electrical Engineering, Zhejiang University, Hangzhou 310027,

China; 2. Shenzhen Power Supply Bureau, Shenzhen 518020, China)

Abstract: Aiming at the problem of three-phase unbalanced voltage sags in the power system, an energy optimization control strategy for a unified power quality conditioner(UPQC) was proposed. Based on the fundamental wave phasor diagram of UPQC during three-phase unbalanced voltage sags, the optimal steady-state power of UPQC was analyzed and the required compensation energy of UPQC was also derived. Based on the principle of minimum compensation energy of UPQC, the injection angle θa、θb、θc of compensation voltage of the series compensation unit was optimized by particle swarm optimization algorithm, and energy optimization control of UPQC was realized by controlling the injection angle of compensation voltage. Simulation results confirm that, the proposed energy optimization control strategy can effectively solve power quality problems and can also reduce the compensation energy of UPQC, thereby the economy of the compensation device is improved.