Planar Structure High-Frequency Transformer Design for Medium Voltage Applications

Planar structure high frequency transformer solution is proposed for medium voltage applications. The high voltage side windings are made of modular PCB boards and high electric field can be well confined within the PCB insulation material by the coated semi-conductive shielding layer. Terminal treatment is implemented to eliminate the possible surface partial discharge and also comply with the creepage requirement. Prototype hardware is fabricated. Test results shows above 11 kVrms partial discharge inception voltage (PDIV).