Compound Current Contorl of the H6 Topology Single-phase Grid-connected Inverter

When the single-phase PV (photovoltaic) grid-connected inverter with H6 topology applies conventional PI controller to track the sinusoidal reference current, the steady-state-error will be generated and its anti-interference capability becomes poor. To deal with this problem, in this paper an compound current control strategy based on quasi-PR (Proportional Resonant) and repetitive control is proposed. The fundamental of the compound current controller is introduced, and the tuning method of the controller parameters is analyzed. The grid-connected current harmonic suppression performance of the designed compound current is validated on a single-phase photovoltaic grid-connected inverter experiment platform.