At the PCIM (Power Conversion Intelligent Motion) Asia 2014 conference in Shanghai World Expo Exhibition and Convention Center, China (17-19 June), Michael de Rooij (executive director, Application Engineering) from Efficient Power Conversion Corp (EPC) of El Segundo, CA, USA, which makes enhancement-mode gallium nitride on silicon (eGaN) power field-effect transistors (FETs) for power management applications, is giving a technical presentation highlighting the efficiency advantage of using eGaN FETs in wireless power transfer applications compared with silicon power MOSFETs ('Performance Evaluation of eGaN FETs in Low Power High Frequency Class E Wireless Energy Converter', 10.35–11.00am, Oral Session – Wide Bandgap Power Semiconductor, 17 June).
EPC will demonstrate the ability of eGaN FETs to be employed in a class-E wireless energy transfer system that shows a 20 percentage point improvement in peak efficiency over a voltage-mode class-D version using the same coils and device load. The designs operate with loosely coupled coils in the 6.78MHz ISM (industrial, scientific & medical) band.
The experimental example demonstrates why the characteristics of the eGaN FETs - such as low input and output capacitance, low package inductances, and small size - make them suitable for wireless power systems. The experimental unit was designed to deliver up to 30W and the EPC2012 eGaN FET allows the class-E system to operate at optimum conversion efficiency. EPC will also demonstrate an even more efficient new topology that can operate with improved stability and reduced component counts compared with the Class E example.
"Wireless energy transfer will be one of the largest and fastest-growing markets for power components over the next ten years," says co-founder & CEO Alex Lidow. "We believe eGaN FETs offer the lowest-cost, most stable and highest-efficiency solution available."
