Patent ID: 7990200
Filing Date: 2011-08-02
Classification: H02M,H03K

Abstract:
1. A PWM (Pulse Width Modulation) control system comprising: a first PWM controller capable of generating a multi-phase PWM signal; and a second PWM controller capable of generating a single-phase PWM signal; wherein a phase difference between the single-phase PWM signal and the multi-phase PWM signal is greater than 0 degree and less than 180 degrees; and the multi-phase PWM signal comprises a first phase signal and a second phase signal that is delayed a cycle relative to the first phase signal, and the single-phase PWM signal is delayed less than a half of the cycle relative to the multi-phase PWM signal; wherein each of the first and second PWM controllers comprises a phase shift module, one phase output of the first PWM controller is connected to the phase shift module of the second PWM controller.