Analysis and control of a reduced switch hybrid active power filter

Abstract

A hybrid B4 active power filter (APF) with reduced switches is proposed in this study, which is composed of a inductance–capacitance ( LC ) passive filter and a four‐switch three‐phase inverter (B4 inverter) in series connection. The LC filter is used to supply reactive power, and the active filter is responsible for mitigating the harmonics. Compared with the previous proposed four‐switch hybrid APF, it can overcome the drawback of large dc voltage components appearing in the ac capacitors. Basic principles and steady‐state analysis of hybrid B4 APF are introduced in detail. A control scheme based on source current detection is presented. Multiple parallel vector resonance controllers are adopted in the current control loop, and the gains of these resonance controllers are optimised by a particle swarm optimisation approach. Experimental results have verified the effectiveness of the proposed hybrid B4 APF.