A Three-Phase AC-AC Matrix Converter with Simplified Bidirectional Power Control for Inductive Power Transfer Systems

The use of direct three-phase ac-ac matrix converter with bidirectional power control for inductive power transfer (IPT) systems is proposed. The converter enables direct power conversion between low-frequency three-phase AC mains and high-frequency IPT systems. A digital power controller is designed and developed to regulate the power transfer rate at the desired level in both directions. A simplified circuit for the bidirectional power controller is presented which can be implemented with a few number of logic components or using a Field Programmable Gate Array (FPGA). The controller enables soft-switching operations and benefits from the resonance frequency tracking capability to maintain the high-efficiency power transmission at any operating conditions. The converter achieves bidirectional power transfer which is specifically useful for establishing grid-to-vehicle (G2V) and vehicle-to-grid (V2G) connections through inductive electric vehicle (EV) charging/discharging systems. Also, the proposed converter can be employed in dynamic IPT systems as it can cope with variations of the system. The controller design methodology, simulation analysis, and the preliminary experimental results of the proposed matrix converter on a case study inductive battery charging system are presented in detail.