JOURNAL OF ENGINEERING-JOE, sa.18, ss.4698-4702, 2019 (ESCI)
LCL filters are widely used in distributed power-generation systems to attenuate high-frequency harmonics caused by pulse-width modulation switching of grid-connected inverters. A resonance occurs due to the series-connected reactive components. In order to damp resonance effects, active and passive damping methods are used. Lower switching frequencies are typically preferred to decrease switching power losses with high-power applications. Thus, control bandwidth of the system is limited and implementation of active damping gets harder. As a result, passive damping methods are commonly used in high-power applications. In this study, performances of two most commonly used passive damping methods which are series R damped and shunt R-C damped are analysed and compared in terms of resonance damping, grid current attenuation at high frequencies, and power losses on damping circuits.