Title |
PWM Method with Low d-axis Current Ripple for reducing Input Current THD at Light Loads in Three Phase PWM Rectifier |
Authors |
Yong-Sin Jin ; Hee-Keun Shin ; Hag-Wone Kim ; Kwan-Yuhl Cho |
DOI |
10.6113/TKPE/2012.17.6.478 |
Keywords |
PWM rectifier; SVPWM; sawtooth carrier PWM; discontinuous PWM; THD |
Abstract |
In this paper, a new PWM method is proposed to reduce the input current harmonics of 3 phase PWM rectifier. In the conventional carrier comparison PWM method, a triangular wave is generally used as the carrier wave. However, the large d-axis current ripple by the triangle carrier wave may be a source of large input current THD(Total Harmonic Distortion). In this paper, a new carrier comparison PWM method with saw tooth wave is proposed. Depending on the sector where the voltage command vector places, one of the rising or falling saw tooth wave is selected. To reduce the switching losses of the saw tooth carrier PWM, the discontinuous PWM is also presented. The proposed PWM method can reduce the d-axis current ripple as well as the switching losses. The performance of the conventional and proposed PWM methods is verified by the simulation and experimental results. |