Isolated power supply serves as the core component which supplies energy to drive circuits of a high-voltage silicon carbide (SiC) device

facing severe challenges in terms of electrical insulation and voltage endurance. Wireless power transfer (WPT)-based isolated power supplies

characterized by their non-contact operation and coreless design

show significant promise for high-voltage and high-insulation applications in SiC devices. However

the insulation properties of existing WPT isolated power supplies remain unclear

and it is difficult to accurately evaluate their voltage endurance capability

which severely restricts performance optimization and practical application. Therefore

a three-dimensional simulation model of the WPT isolated power supply was established

and the influences of three key parameters

namely

the relative distance

the wire diameter

and the number of turns of the coils

on the electric field distribution and maximum field strength were elucidated. Subsequently

a high-voltage discharge experimental platform was constructed to investigate the relationship between key structural parameters and insulation discharge characteristics based on following four indicators: the partial discharge inception voltage

the maximum discharge magnitude

the number of discharge pulses

and the total discharge quantity. The insulation properties of the WPT based power supply under various structural parameters were clarified. Finally

the influence mechanisms of each structural parameter on the insulation performance of WPT based isolated power supplies were elucidated. This research offers a theoretical foundation and experimental support for the optimization of insulation performance and reliable application of WPT based isolated power supplies.