Stability performance of two-stage PFC converters under nonlinear-carrier control and average-current-mode control

This paper deal with two different control circuits for two-stage PFC converter, nonlinear control (NCC) and average-mode-control (AMC). Studying these systems result in two different characteristics from stability point of view. In average-current-mode control, heavy loads become more susceptible for instability at higher dc gain of the dc-dc converter. However, with resistive load, system is more susceptible for instability at light loads. On the other hand, nonlinear control remains carrying same features like resistive loads, more susceptible for instability at light loads. Simulations using PSIM in the form of time domain waveforms and maps in the some useful parameter spaces are given to illustrate the results. Experimental results confirm agree with simulation.