Conduction noise reduction method for the three-level V-connection inverter using space vector PWM

This paper proposes a new Space Vector PWM (SVPWM) method for reducing the neutral point potential variation of the three-level V-connection inverter. In the proposed method, by selecting the vectors which has low neutral point potential variation to generate the output voltage command value, the neutral point potential variation of the V-connection inverter can be reduced. In addition, the neutral point potential variation influences the magnitude of the common-mode leakage current of the load. Moreover, the common-mode leakage current is dominant to the generation of the common-mode noise. Therefore, it can be considered that the proposed SVPWM can reduce the common-mode noise by reducing the neutral point potential variation. After that, the experimental comparison about the conduction noise in the frequencies below 150 kHz is discussed. From this result, the effect of the proposed method can be confirmed. In the frequencies below 100 kHz, it can be confirmed that the conducted emission is reduced by maximum 16 dB when using the proposed SVPWM method. Furthermore, based on this result, it can be understood that the volume of the common-mode choke of the EMC filter can be reduced when using the proposed method.