Rechargeable Electrets for Electric Field Cancellation in Wide Bandgap Power Electronic Systems

There is a growing demand for compact, high-performance power electronic systems for all-electric ships, aircraft, and advanced energy systems. This demand is largely driven by the widespread adoption of wide bandgap (WBG) semiconductors such as silicon carbide (SiC) and gallium nitride (GaN), which offer significant advantages over traditional silicon (Si) devices. WBG semiconductors can operate at higher voltages, higher switching frequencies, and elevated temperatures, all while maintaining greater efficiency and reduced switching losses. These characteristics make WBG devices ideal for use in electric vehicles, renewable energy converters, motor drives, and power systems for marine and aerospace applications. However, these advances also introduce new dielectric challenges. The faster switching speeds and steeper voltage transients associated with WBG/UWBG devices significantly increase localized electric fields, leading to partial discharge and surface flashover.

 

Prof. Chanyeop Park at Arizona State University has developed a novel technology that leverages rechargeable electret thin films—negative, positive, and bipolar types to counteract harmful electric fields in WBG/UWBG power electronics. By reducing partial discharges and surface flashovers, these films increase partial discharge inception voltage (PDIV) and decrease dielectric losses, maintaining performance even at temperatures above 175°C through self-recharging via natural leakage currents. Applied to critical high-field regions, this technology improves insulation reliability and enables more compact, power-dense designs in advanced electrical systems.

 

This novel rechargeable electret thin film technology mitigates electric field concentrations to enhance reliability in wide bandgap power electronic systems.