Optimal design of LCL harmonic filters for three-phase PFC rectifiers

Inductive components such as line filter inductors or transformers occupy a significant amount of space in today's power electronic systems, and furthermore, considerable losses occur in these components. A main application of filter inductors are EMI filters, as e.g. employed for the attenuation of switching frequency harmonics of PFC rectifier systems. In this paper a design procedure for the mains side LCL filter of an active three-phase rectifier is introduced. The procedure is based on a generic optimization approach, which guarantees a low volume and/or low losses. Different designs are calculated to show the trade-off between filter volume and filter losses. The design procedure is verified by experimental measurements.