Current-loop gain with a nonlinear compensating ramp

It is revealed for the first time that the crossover frequency of current-loop gain can be designed to be independent of duty ratio if a nonlinear compensating ramp, instead of a linear ramp, is used. This unique property allows current programming to be extended to (active) AC-to-DC and DC-to-AC power converters, where duty ratio is constantly changing. The basic principle behind this technique is first presented. Current-loop gain and the invariance of crossover frequency are then established. Measurement of current-loop gain for different values of duty ratio supports analytical predictions.