An On-Board Two-Stage Integrated Fast Battery Charger for EVs Based on a Five-Phase Hybrid-Excitation Flux-Switching Machine
Minghao Tong, Ming Cheng, Sasa Wang, Wei Hua
Abstract
In this article, to solve the existing problems in general on-board integrated chargers, a novel three-phase on-board two-stage integrated charger is proposed by taking the unique advantages of a five-phase hybrid-excitation flux-switching (HEFS) motor. The general topologies and newly presented integrated chargers are reviewed first, and existing problems are concluded. Then, a two-stage integrated charger is proposed, and all winding selections are thoroughly investigated by theoretical analysis, finite-element analysis (FEA), and experiments. In the proposed topology, the existing problems are all solved by employing this multiphase system, reasonable winding selection, and reconfiguring the field winding. After that, a current balance control method for charge mode without a phase-locked loop circuit is presented. The simulation results verify the effectiveness of the proposed control methods. Finally, based on a 5-kW five-phase HEFS prototype machine and two sets of the three-phase generic motor controller, an experiment platform is built. The experiment results agree well with the simulation results. Therefore, the feasibility of a two-stage integrated on-board charger that can operate at any voltage level is confirmed, where only the hybrid-exciting machine and its driving system are used without any additional power devices.