Analysis and design of an unusual unity-power-factor rectifier

A unity-power-factor rectifier that has a parallel-resonant tank tuned to the second harmonic of the line frequency is analyzed for two filter configurations. A unidirectional-power-flow version of the current-sourced rectifier can operate stably open loop or can be current limited down to zero output voltage. The large inductor normally required is an outstanding disadvantage which can be partially overcome using a resonant filter. The design-oriented analysis includes variable-frequency operation and key component ratings. A design procedure is suggested, and complete experimental verification is obtained using a 120 V, 500 W. 60 Hz rectifier switching at 50 kHz