Two-Switch Dual-Buck Grid-Connected Inverter with SPWM Control and Single Current Sensor

This paper presents a two-switch dual-buck grid-connected inverter with sinusoidal pulse-width modulation (SPWM) control and single current sensor. The freewheeling current flows through the independent diodes instead of the body diodes of the switches, so reverse recovery losses of the diodes can be reduced. Half of the power devices operate in high frequency at each half line cycle, and the others switch at grid period and can realize zero-current switching (ZCS), thus the efficiency can be increased. Moreover, uniploar modulation is adopted. Therefore, weight and volume of the output filter can be decreased. SPWM control is adopted, so the output filter is easy to design. Only one current sensor is used. The operating principle is illustrated. Finally, simulation results verify the theoretical analysis and satisfy the IEEE Std. 929-2000.