A novel single-stage off-line converter with PFC and fast output voltage regulation

A single-stage, isolated, low cost, LC resonant based power supply circuit incorporating power factor correction and fast output voltage regulation is proposed. Advantages of this topology include soft switching of power devices, output voltage holdup and control loop simplicity. The recently introduced rectifier compensated fundamental mode approximation (RCFMA) method is used to provide an accurate yet simple analysis of the circuit. This approximation is extended to provide a small signal model of the converter which is used to design the control loop. Results from a 5 V, 20 A prototype are presented.