A Novel Grid-Connected Converter with Active Power Filtering Function

A Novel Grid-Connected Converter with ActivePower Filtering Function was proposed. Considering the specific situation, main circuit and controller were designed. The proposed system can exchange active power with grid and/or compensate harmonic current and reactive power of grid at the same time or respectively. LCL type filter was adopted to attain a good filtering effect. Proportional Integral (PI) control, repetitive control as well as feed forward control which can gain better dynamic performance composed the control system. To track the time-varying active current value, the influence of time lag caused by repetitive control during the fast switching period was considered. DC link voltage controller was designed for its special applications. Simulation results verify the high steady state precision and fast dynamic response of the system.