Zero-crossing distortion inhibition method of three-phase dual-buck inverter

This paper proposes the zero-crossing distortion inhibition method of three-phase dual-buck inverter with LCL filter. The half-cycle pulse-width modulation (PWM) of the dual-buck inverter would cause zero-crossing distortion. The cause of zero-crossing distortion is analyzed and the inhibition method is presented. Half-cycle space vector PWM (SVPWM) is applied as the control strategy of the inverter. The negative feedback of grid current harmonic components can change the reference of the space vector at zero-crossing period. Thus the amplitude of the current ripple can be reduced. When it is close to zero, the zero-crossing distortion can be inhibited. A prototype of three-phase dual-buck inverter has been built and tested to verify the theoretical analysis.