Passivity-based LCL Filter Design of Grid-Connected VSCs with Converter Side Current Feedback

This paper presents a design method for LCL filters used in grid-connected voltage source converters (VSCs). The converter-side current feedback and the filter-capacitor voltage feedforward control methods are used. Besides the harmonic current injection limit, the passivity of the input admittance of VSCs is also considered for a co-design of the controller gains and passive filter components. Thus, the stability of current control can be ensured against the grid impedance variation. The effectiveness of the method is confirmed by simulations and experimental tests.