Feedforward Compensation for One-Comparator Counter-Based PWM Control Based on FPGA

A feedforward compensation technique is presented herein and applied to one-comparator counter-based PWM control based on the field programmable gate arrays (FPGA). By changing the amplitude of the injected sawtoothed wave, the effect of variations in the input voltage on the output voltage is significantly reduced and makes the converter work well over all the operating range. In this paper, the proposed control topology is described in details and applied to the buck converter with synchronous rectification (SR). Some experimental results are provided to demonstrate this strategy.