Design of Duty-Ratio and Phase-Shift Control Circuits for MPPT of SPV Source using ZV-ZCS PSFB Converters

This paper presents two separate control circuits for a soft-switching phase-shift full-bridge (PSFB) pulse-width modulated (PWM) dc-dc converter. The PSFB converter is operated with maximum power point tracking (MPPT) controller to extract maximum power from a solar photovoltaic (SPV) source, either by controlling the duty ratio or by varying the phase-shift angle of switching gate pulses. The MPPT controller is used in the feed forward voltage control loop of SPV source. Both the duty ratio and the phase-shift controllers have been tried with conventional PID controller and linear quadratic Gaussian (LQG) controller for performance comparison in MATLAB environment. Finally, experimental studies have been performed to verify the ability of the controllers to extract maximum power from the SPV source using the PSFB converter.