Performance analysis of high conversion ratio converter with switched capacitor and voltage gain extension cell

A novel converter with switched capacitor and voltage gain extension cell is proposed in this paper to satisfy the high voltage gain requirements. In the proposed converter, the switched capacitor is applied to extend the voltage gain and reduce the voltage stress of the switch. A voltage extension cell circuit is adopted to further improve the voltage conversion ratio. Meanwhile, the leakage inductance of the coupled inductors limits the current rate, which reduces the pulsed current significantly when the switch turns on. Furthermore, the leakage energy is absorbed and transferred to the load, and the switch voltage is clamped when it turns off by the switched capacitor. Finally, a 48V-input 380V-output 500W prototype is built to demonstrate the theoretical analysis, and the maximum efficiency of 96.5% and 95.2% at full load are achieved.