A novel method for reducing common mode voltage base on improved SVPWM in three-phase PV inverter

The present paper proposed an improved space vector pulse width modulation (SVPWM) method for reducing common mode voltage. Non-zero vectors which were generated by exchanging the specific two arms' switching patterns were applied to reduce the common mode voltage instead of zero vectors. On contrast with the conventional SVPWM strategy which brings in the common mode voltage in typical three-phase inverters, the proposed method can reduce the peak-to-peak amplitude of the common mode voltage to 1/3, without any additional volume, weight or cost, implemented totally by software. Furthermore, the method can also be applied conveniently in the inverters controlled by SVPWM with deadband compensation. Simulation on a 10kW three-phase photovoltaic inverter was performed to verify the validity effectiveness of this method.