Robust voltage regulation of DC-DC PWM based buck-boost converter

Abstract

This paper investigates the performance of DC-DC PWM based buck-boost converter with two degree-of-freedom (2 DOF) control to meet the loop robustness goals as well as to shape the output voltage response according to requirement. The design technique of this controller is simpler than that of the robust control techniques, such as H∞, control, μ-synthesis, applied in literature for converters. Moreover, 2 DOF control is already established in literature to provide robust compensation to boost converter. The performance of the buck boost converter is examined in the presence of (i) 60% perturbation in load current, (ii) 25% perturbation in input voltage and (iii) high frequency measurement noise. The 2 DOF control scheme has been shown to achieve the output regulation and obtain fast recovery in output voltage response, through simulation.