Constant-current-output inverter wins GaN company’s university challenge

July 07, 2016 // By Graham Prophet
Post-graduate students at London’s Imperial College have won recognition in a design challenge set by gallium-nitride-device maker GaN Systems, an exercise carried out in association with the UK EPSRC Power Electronics Centre to accelerate the use of high speed GaN transistors in future power conversion or control applications.

A post-graduate team from Imperial College London received the £2,000 prize for winning the first, annual GaN Systems Geoff Haynes Future Power Challenge. Sponsored by GaN Systems, the competition was open to all UK power electronics postgraduate students who submitted research papers or posters that contributed to accelerating the use of GaN transistors in future power conversion or control applications. Prof. Mark Johnson of The University of Nottingham and Prof. Barrie Mecrow of Newcastle University judged the competition at the annual summer school event organized by the PhD students of the 10 Universities that form the EPSRC power electronics centre. The summer school is a student-led event intended to increase communication and co-operation between the student research teams and to provide an opportunity for the students to meet with prospective employers and research partners. Entries covered subjects as diverse as the design of a novel compact motor with embedded filter windings, through a reliability study and optimized PWM control strategy for an A-NPC converter.


Ph.D. students George Kkelis and Juan Arteaga, and research assistants Sam Aldhaher and David Yates from Imperial College London’s Department of Electrical and Electronic Engineering, supervised by Dr. Paul Mitcheson, first presented their work at the IEEE Wireless Power Transfer Conference in May 2016. The team developed two inverter prototypes, each based on a Class EF topology using GaN Systems’ GS66504B switches. Their new design maintains zero-voltage switching and delivers a constant output AC current regardless of the load resistance value. The design allows a Class E or Class EF inverter to operate efficiently for any load. This was shown to significantly relax the requirement for accurate alignment of transmit and receive coils in a wireless power application.


The GaN Systems Geoff Haynes Future Power Challenge was established in recognition of Mr. Haynes’s critical role in establishing GaN Systems, and championing the use of gallium nitride for power applications. Geoff Haynes retired last year