PWM series resonant DC-link converter with current clamping by the use of saturable core

A series resonant DC link power converter with pulsewidth modulation (PWM) capability and current peak limiting is proposed. When desired, a resonant transition creates notches in the DC link current, allowing the switches of the power converter to synchronize with external PWM strategy. For that, it requires only an additional bidirectional switch. A saturable core (SC) achieves current peak limiting of which the clamping level is automatically adjusted by the current load. Analysis and design procedure are presented for the proposed topology, which does not use any dedicated devices for startup. Simulated and experimental results corroborate the theoretical studies.