A Single-Stage Bidirectional Inductive Power Transfer System With Closed-Loop Current Control Strategy

• Published in: IEEE transactions on transportation electrification Vol. 6; no. 3; pp. 948 - 957
• Main Authors: Vardani, Bharat, Tummuru, Narsa Reddy
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 01.09.2020; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: AC-DC power converters; AC/AC converter; ac/dc converter; Alternating current; Batteries; bidirectional power flow; Capacitors; Control systems; Conversion; Electric converters; electric vehicle (EV); Electric vehicles; Hardware; inductive power transfer (IPT); Parameter estimation; Pickup coils; Power factor; Reliability; series–series (SS) compensation scheme; Strategy; Topology; Transient response; Transportation; wireless charger; Wireless power transmission
• ISSN: 2332-7782; 2577-4212; 2332-7782
• DOI: 10.1109/TTE.2020.3003749

A conventional two-stage topology that consists of a dc/ac converter, a dc-link, and two ac/dc converter is being used as wireless charging of electric vehicles (EVs). However, the conventional topology contains more conversion stages with a bulky dc-link capacitor, and implementation of control strategies is not easy to transfer power from the primary coil to pickup coil or vice versa. A single-stage, inductive power transfer (IPT) system with a simple control strategy is needed to reduce the conversion stages and to increase the reliability of the system. This article proposes a control strategy for a single-stage conversion topology that is easy to implement and more importantly can achieve unity power factor (UPF) using a single controller. The experimental validation of single-stage conversion topology and steady-state analysis with series-series (SS) compensation scheme is presented in this article. A fixed angle of ±90° in between the output phase of the converters is achieved without estimating any power or current parameters. A hardware prototype working at a lower watt rating is analyzed, and the validation of the proposed system for 3.7-kVA rating as per the international standard is simulated. Furthermore, transient response is also observed to verify the closed-loop control scheme of battery current.