A New Controller for Bi-directional Inductive Power Transfer Systems

Inductive Power Transfer (IPT) technology is gaining popularity as an efficient technique for supplying contactless power to numerous applications. In contrast to unidirectional IPT systems, bi-directional IPT systems invariably require more sophisticated and effective control strategy to regulate the power flow within the limits of power capability of converters. This paper proposes a new controller that uses power-frequency droop characteristics to regulate the power flow of the system without any additional communications. Simulated results of a 2 kW bi-directional IPT system with a single pick-up are presented with discussions to show that the proposed droop controller can effectively be used regulate the power flow, while limiting the power flow at maximum level when necessary.