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 uni-directional 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.