Second Harmonic Active Suppression Converter for Battery Pulsating Current

This paper proposes a second harmonic active suppression converter (SHASC) to suppress the second harmonic current (SHC) generated by the two-stage single-phase inverter (TSI). The SHASC converter consists of an intermediate DC bus capacitor and a full-bridge circuit. One side of the full-bridge circuit serves as the input port, through which the intermediate DC bus capacitor is connected to the DC bus of the single-phase grid-connected inverter. The other side acts as the output port, connecting the intermediate DC bus capacitor to the battery energy storage system (BESS). By actively controlling the half-bridge on the input side of this converter, the intermediate DC bus capacitor can absorb the SHC output by the TSI, thus actively suppressing the SHC at the battery terminals. Compared with existing solutions, it reduces the size of passive components and the complexity of control.