Active Power Filter Based on Four-leg Hybrid-Clamped Technique

Parallel active power filter based on four-leg hybrid-clamped converter topology is proposed in this paper. The detailed description is given on the balancing principle of capacitors´ voltages with four-leg hybrid-clamped technique. An independent leg operating as a clamping leg brings better performance and easy control. For levels larger than live, this topology is a better choice when the ability of voltage balance and simple control are considered. The simulation and experiment of active power filter based on this topology show good performance of voltage balance and compensation.