A review of passive power filters for voltage-source converters

Abstract

Passive power filters are necessary for attenuating the switching frequency harmonics introduced by the modulation of power converters. Recently, various topologies of novel passive power filters have been proposed to enhance their respective attenuation ability with relatively small filter components, i.e., filter inductors and capacitors. This paper reviews the state-of-the-art passive power filters for voltage source converters. Specifications, such as the high frequency roll-off rate, robustness against grid-impedance variation, structure complexity, and implementation costs, are utilized to evaluate the performances of individual passive filters. The analysis provided in this paper reveals that the LCL filter together with a paralleled LC-trap in the converter-side can be the most promising passive filter. Finally, simulation and experimental results are presented to validate the effectiveness of theoretical analysis.