Comparison of L, LC & LCL filter for grid connected converter

Distributed generation penetration has increased in the last decade and VSC (Voltage Source Converters) are used to integrate these with grid. The power obtained from these VSCs should be of high quality but switching of semi - conductor devices causes harmonics in the voltage and current waveforms. Efficient filtering is required to ensure aimed quality and operation of all equipments. L and LC filters were popular till now, but with increased power quality stresses, the value of L increases which becomes less economic. LCL filter provides an attractive alternate for the L and LC configuration. This paper compares performance of LCL, LC and L filter for grid connected VSCs.