A Decentralized Control Scheme for Active Power Filter Parallel System

In high power application, a single active power filter (APF) limited by its capacity cannot compensate for whole harmonics. APF parallel system is thus adopted to solve this problem. Centralized control scheme for the parallel system features good current sharing ability, but subject to communication fault. On the other hand, decentralized control schemes cannot share current properly. This paper proposes a decentralized control scheme for modular APF parallel system in which all APF modules have equal status and share the current in proportion to their own capacities without central controller. What is more, plug and play of an APF is achieved, and current sharing can be done automatically. The correctness and effectiveness of the scheme have been testified by simulations.