Abstract:
Inductive power transfer power supplies for electric vehicle charging in dynamic applications need to tolerate large variations in coupling and tuning with varying loads. This paper investigates the use of a buck converter to regulate the input voltage to a fixed frequency unidirectional switch push-pull converter to meet the requirements of dynamic charging. The presented circuit is optimized to remove some of the additional components introduced. A mathematical model is presented that shows the circuit is capable of operating while extremely mistuned in both the inductive and capacitive regions while maintaining sinusoidal currents. A controller design is also presented allowing constant primary current operation, safe start up, and operation under no load conditions. A 5-kW prototype was built and validated when operated with a dynamic load under severely mistuned conditions.