A Parallel-APF System with Current Sharing Controller and Load-Path Control Center to Improve Dynamic Response and Achieve Weighting Current Distribution

This paper presents design and implementation of a paralleled active power filter (APF) system with current sharing controller (CSC) and load-path control center (LPCC). This system can filter harmonic currents, compensate reactive power and improve power factor. In the system, each APF module is directly tied to the load, source and buses, and there is no need of communication with other modules. Through CSC and LPCC, the modules can share the total reactive and harmonic currents of the loads according to their power ratings. With the proposed control scheme, power capacity of the system can be readily and flexibly expanded. Since there is no communication between modules, system expandability and flexibility will increase, and hot-swap feature can be readily achieved. Simulations and experimental results have verified the feasibility and performance of the proposed parallel-APF system