A Nine-Phase Permanent Magnet Electric-Drive-Reconstructed Onboard Charger for Electric Vehicle

摘要

This paper presents a novel approach for an electric-drive-reconstructed onboard charger (EDROC) for electric vehicles incorporating a symmetrical nine-phase permanent magnet machine. To implement three-phase power factor correction and propulsion battery voltage/current regulation, an exclusive utilization of the nine-phase propulsion system is developed. First, a paralleled three-phase pulsewidth-modulated voltage source rectifier is reutilized from six inverter legs and is directly connected to the three-phase utility grid through six-phase out of the machine stator windings. Second, a three-phase buck-type converter is reconstructed by the remaining three-phase inverter legs and machine windings. Third, to realize zero electromagnetic torque production during the three-phase charging mode, the rotor parking position is applied in the decoupling transformation matrix. Moreover, control schemes for a charging mode including current balancing and interleaving strategy are elaborated. To evaluate the steady-state and dynamic behavior of the proposed EDROC system under different operation scenarios, 3.3-kW laboratory prototype based tests have been conducted.