Closed-loop voltage-mode-controlled PWM flyback dc-dc converter for CCM with integral-lead controller

Abstract

This paper presents an analysis of a closed-loop voltage-mode-controlled pulse-width-modulated (PWM) flyback dc-dc converter for continuous conduction mode with an integral-lead controller. An integral-lead controller is designed so that it completely meets the system specifications. The closed-loop dynamic performance of the system is analyzed. The Bode plots are illustrated for closed-loop control-to-output transfer function, input-to-output transfer function, input impedance, and output impedance. Tile system stability is evaluated with the results of 45/spl deg/ for the phase margin at the crossover frequency of 2.5 kHz, and 6 dB for the gain margin at a frequency of 5 kHz at a duty cycle of 0.45.