Patent ID: 6049473
Filing Date: 2000-04-11
Classification: H02M,Y02B

Abstract:
A control circuit for controlling a single-switch boost rectifier, said single-switch boost rectifier receiving a three-phase AC input signal and providing a rectified output signal, said control circuit comprising:an output feedback circuit receiving said rectified output signal of said single-switch boost rectifier and a reference signal, and providing an error signal representing a voltage difference between said rectified output signal and said reference signal;a feedforward control circuit coupled to receive said three-phase AC input signal and providing a variable-slope ramp signal having a slope dependent upon a magnitude of said three-phase AC input signal;a ramp voltage generator providing a nonlinear-slope ramp signal;a summer summing said variable-slope ramp signal and said nonlinear-slope ramp signal to provide a third ramp signal; anda pulse-width-modulated (PWM) modulator coupled to receive said third ramp signal and said error signal to provide a signal for switching said single-switch boost rectifier.