Partial Discharge Improvements of Isolated Transformer in Medium-Voltage Gate-Driver Power Supply

With the advancement of medium-voltage power devices, ensuring robust isolation and interference immunity for medium-voltage gate drivers has become a critical focus in both industry and academia. Among the critical components, the gate-driver power supply transformer poses the most significant challenge. Typically, the voltages on either side of the winding remain in the range of tens of volts, while the primary-to-secondary voltage difference can be thousands of volts. To address this unique application, this paper provides detailed insights into partial discharge considerations for improving design. Simulation results reveal that the electric field distribution of the improved transformer becomes more uniform. Furthermore, partial-discharge test results demonstrate a remarkable 74% increase in the partial-discharge inception voltage. Additionally, the paper conducts a 6 kV / 30 A double pulse test and continuous test, showcasing robust performance of the transformer.