Abstract
This paper describes low-voltage and large-current DC power supplies with a high-frequency transformer coupling. Two different power supplies were developed with different configurations and operation characteristics of the two were experimentally examined in this paper. Both power supplies are simply composed of a full-bridge inverter, an amorphous-core step down transformer and a schottky diode rectifier. One power supply operates on the magnetizing frequency of 15kHz, and generates 13-V and 5000-A output. The other generates 12-V and 4000-A output, but introduces only 1-kHz magnetizing frequency due to a long overlapping period in commutation caused by large leakage inductance of its transformer. The maximum total efficiency of the former and the latter is 89.9% and 85.7%, and the total input power factor of the two is 83.5% and 92.8%, respectively. Although the output voltages and currents of the two prototypes are considerably low and large, these experimental results demonstrate excellent performance.
