A Two-Stage Parameter Optimization Method for Capacitive Power Transfer Systems

• Published in: IEEE transactions on power electronics Vol. 37; no. 1; pp. 1102 - 1117
• Main Authors: Xia, Jinglin, Yuan, Xinmei, Lu, Sizhao, Li, Jun, Luo, Shuling, Li, Siqi
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.01.2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: C++ languages; Capacitive power transfer (CPT); Capacitors; Circuit design; Commercialization; Configuration management; Couplers; Couplings; Design optimization; electric field resonance; Integrated circuit modeling; Misalignment; Optimization; parameter design; Parameters; Power consumption; Reactive power; reactive power optimization; Systems design; Topology; Transportation systems; wireless power transfer (WPT); Wireless power transmission
• ISSN: 0885-8993; 1941-0107
• DOI: 10.1109/TPEL.2021.3097344

Wireless power transfer (WPT) is more convenient and safer than conductive charging for power consumer electronics, biomedical devices, transportation systems, etc. Inductive power transfer is the most widely studied and commercialized WPT technique; however, capacitive power transfer (CPT) is becoming an attractive alternative, offering better misalignment tolerance and lower cost and weight. The electrical-field-resonance-based six-plate coupler system is one of the most typical configurations for high-performance CPT systems, but the associated large number of circuit parameters is always a critical issue for system design. In this article, a parameter optimization method is proposed for this topology. The ratio of the reactive power in the compensation network to the system transferred power is set as the main optimization goal. To solve the high-order optimization problem, a two-stage method is proposed to significantly reduce the optimization complexity while providing the optimized parameters of the whole system. To verify the effectiveness of this method, a 3-kW, 1-MHz CPT system with a 16-pF coupling capacitor is built. Both the simulation and experimental results show that the optimized parameters effectively improve the system efficiency, experimentally achieving 95.7% dc-dc overall efficiency under a 100-mm gap distance at the rated power.