Aiming at the problems of limited semiconductor performance and positioning difficulties in the wireless power transfer (WPT) system of electric vehicles, the paper proposes a many-to-one high-voltage wireless charging anti-offset system. In order to be adapted to high-voltage applications, the system is designed with a series input inverter. At the same time, a multi-winding transformer is used to realize the equivalent parallel output of inverters and the function of transmitting power to primary loops. The many-to-one topology aims to expand the positioning range of electric vehicles to realize the anti-offset of wireless charging. In order to analyze the working mechanism of the multi-winding transformer and study the power transmission characteristics of the many-to-one topology, the equivalent circuit analysis and Matlab simulation are carried out, and a laboratory prototype for experimental verification is made. Based on the experimental and simulation results, the paper proposes a hybrid operating mode based on many-to-one WPT topology, which can effectively expand the positioning range of electric vehicles during wireless charging. Both the analytical and experimental results show that the topology proposed in the paper can effectively increase the input voltage of the system for high-voltage scenarios, and effectively expand the positioning range of the WPT system.

In this article, the immersed lithium-ion battery module’s liquid cooling and heat dissipation scheme are studied, and the heat dissipation characteristics of the large-capacity battery module after the battery is grouped are analyzed. The simulation models of the liquid cooling system’s five inlet and outlet layouts are established. The numerical results show that immersed liquid cooling method can effectively prevent and reduce the temperature rise of large-capacity battery modules. The layout of the imports and exports can influence the heat transfer effect, which is of guiding significance for the design of immersed protective fluid heat dissipation of lithium-ion battery modules.

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In this paper, a parallel modular multi-inverter (PMMI) topology is proposed to supply high power for wireless charging electric vehicles (EVs). A major challenge in the implementation of PMMI topology is zero-voltage switching (ZVS) for all inverters to avoid high-frequency switching losses. Therefore, a centralized-ZVS control and master–slave frequency following (MSFF) strategy are presented to realize ZVS for all PMMIs by a single controller structure without extra controllers needed on the slave inverters. Meanwhile, a modeling method directly related to the ZVS angle and operating frequency for an arbitrary number of PMMIs is proposed and linearized to analyze the system dynamic characteristics at the operating point. Additionally, to obtain the desired dynamic performance, an optimal controller coefficient (OCC) configuration method is proposed for the design of controller parameters. Finally, a laboratory wireless power transfer (WPT) prototype supplied by three PMMIs is designed, built, and tested to verify the correctness of the theoretical analysis. Experimental results show that the ZVS angle of all PMMIs can maintain at the preset value with the desired settling time under designed the PI controller parameters. The measured whole system power transmission efficiency is 94.1% at a 10 Ω load.

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