Dual-repetitive control algorithm for three-phase Shunt Active Power Filters

Shunt Active Power Filters (APFs) have been proved useful to correct distorted currents caused by nonlinear loads in power distribution systems. This paper presents a dual-repetitive control algorithm, which consists of one fundamental repetitive period to ensure the APFs´ high tracking precision of both even and odd harmonics, and the other harmonic repetitive period to enhance the dynamic response of the controller. Compensation performance of APF with this dual-repetitive controller is compared with the ones of using PI and single repetitive and is tested for unbalance nonlinear load by simulation in Matlab/Simulink environment. The results verify the validity and superiority of dual-repetitive control algorithm in APF application.