A Load Test Method Using Two Power Supplies for High- Frequency Transformers

Abstract

This paper proposes a load test method for high-frequency transformers using two power supplies. In the proposed method, two power supplies need to supply only power losses of the transformer because the power is circulated between the primary side and the secondary side. Hence, the load test of high-frequency transformers whose capacity is larger than that of the power supply can be performed without a high-frequency load. The experimental result shows that the load test of the transformer under 100-kHz sinusoidal voltages/currents was performed using two power supplies whose capacity was 50 VA/unit, much smaller than the rated capacity of the transformer, which was 900 VA. Furthermore, it was confirmed that the load test can be performed at all power factors from 0 to 1. In addition, experimental results show that the accuracy of power loss measurement was improved compared with an existing method that obtains the power loss by subtracting the output power from the input power of the transformer.