Nonlinear PWM controller for a single-phase half bridge AC-DC converters

The problem of controlling half bridge single phase unity power factor rectifier circuit is considered. The control objectives are to achieve i) output regulation and ii) near unity power factor in the presence of an uncertain load. The considered problem is dealt with using a double-loop controller developed on the basis of the system nonlinear model. The inner-loop is designed using Lyapunov technique to cope with the PFC issue. The outer-loop is designed to regulate the converter output voltage. The obtained regulator is shown to meet its objectives namely a tight output voltage regulation, a power factor correction, and robustness with respect to load changes. The proposed controller has been simulated using MATLAB-SIMULINK environment to illustrate its features.