Feed-forward pulse-width modulators for switching power converters

This paper describes novel pulse-width modulators that employ feed-forward compensation to improve steady-state and dynamic responses of power converters. It is shown how ideal feed-forward pulse-width modulators (FF-PWM) can be constructed for all duty-ratio controlled switch-mode power converters. A converter with FF-PWM at low frequencies behaves as a linear power amplifier with constant gain independent of operating conditions. The proposed FF-PWM can be easily implemented using the same building blocks found in conventional PWM controllers. Experimental and simulation examples are presented.<>