A Single-Stage Universal Input Wireless Inductive Power Transfer System With V2G Capability
Jalaj Kumar, Suvendu Samanta
Abstract
This paper reports a new single-stage wireless inductive power transfer (IPT) topology, which accepts both AC and DC input for EV battery charging applications. Also, the proposed system has bi-directional power flow capability; hence, the V2G operation is feasible. On the grid side, an AC-AC matrix converter converts the line frequency AC directly into high-frequency AC, thereby eliminating short-lived bulky DClink capacitor. Achieving a unity power factor with traditional IPT topology is challenging because the front-end converter always has a buck-derived configuration. In this paper, a boostderived topology with bidirectional power transfer capability is proposed, which can maintain a unity power factor at the grid. The proposed single converter has three distinct operating modes- a) Grid to Vehicle (G2V), b) Solar to Vehicle (S2V) or the DC-DC, and c) Vehicle to Grid (V2G) mode. The steadystate operation, converter dynamic modeling based on smallsignal analysis, and closed-loop control are reported for all the operating modes. The soft-switching performances are analyzed for the AC-AC converter and battery-side converter switches. A 700 W laboratory prototype is built, and the experimental results are presented to verify the analysis and performance of the proposed single-stage universal IPT topology.