An Enhanced Passivity-Based Control of Grid-Connected Voltage Source Inverter with LCL-filter

Passivity-based control has been used for grid-connected converter to improve the system performance. An enhanced passivity-based control and detailed design method of control parameters based on passivity theory are proposed for three-phase grid-connected LCL-filtered voltage source inverters (VSIs). The influence of control delay for PBC is considered and output admittance shaping method is derived to extend the stability region of the system up to the Nyquist frequency under complex grid impedance. Simulation results demonstrate the effectiveness and robustness of the control design.