An Improved Dual-Buck with Common-Mode Leakage Current Suppression

In order to suppress the common-mode leakage current in non-isolated grid-tied inverter photovoltaic system and improve the reliability of it, an improved dual-buck inverter circuit topology is proposed. The circuit topology can effectively suppress the common mode current, improve the problem of low inductance utilization in the traditional dual-buck inverter circuit topology, and ensure the common ground of the high-frequency switching transistor source, which is conducive to the drive design. In addition, a modulation method based on carrier phase-shifted control is introduced, which can reduce the output ripple current of the inverter without increasing the switching frequency, which is conducive to improving the power density of the system. The operation principle and characteristics of the proposed topology are analyzed in detail, and the specific implementation scheme of the modulation method is given. The feasibility of the circuit topology and modulation method is verified by a 1kW principle prototype.