A New Family of Soft-Switching DC-DC PWM Converters Using a True ZCZVT Commutation Cell

In this paper is introduced a new family of DC-DC PWM converters using a true Zero Current and Zero Voltage Transition (ZCZVT) commutation cell. The soft-switching technique utilized provides Zero Current Switching (ZCS) and Zero Voltage Switching (ZVS) simultaneously, at both turn-on and turn-off of the main switch and ZVS for the main diode. The family of ZCZVT PWM converters is obtained from an common equivalent circuit of ZCZVT PWM converters and the ZCZVT PWM boost converter is analyzed, simulated and implemented. It is demonstrated the construction of state-plane diagram, which is obtained by using a proper state variable transformation. Based on the commutation analysis and the relations between the most important circuit parameters, it is presented a design guidelines and a design example. Experimental results are presented, taken from a laboratory prototype rated at 1 kW, input voltage of 155 V, output voltage 340 V and operating at 40 kHz. The measured efficiency at full load was 97.9 %.