Active Control Strategy of Partial Discharge for Insulation of High-Power High-Voltage High-Frequency Transformers (H3Ts)

The insulation coordination design against electric-originated complex operation conditions is one of the critical challenges for high-power, high-voltage, high-frequency transformers (H3Ts) in solid-state transformers. The connection between the insulation performance and the operational parameters of H3T is tightly coupled, but their interaction has been ignored till now. In this letter, an active control method is proposed by adjusting the voltage amplitude, frequency, and temperature to decrease partial discharge (PD) to improve the high reliability of H3T. At first, PD versus voltage level, frequency, and temperature in existing typical insulation are identified. Then, the PD rules of different parameters are utilized to provide feedback information and guideline for the control of H3T. This letter aims to improve the reliability of H3T through active control of PD activities.