An integrated Driving/Charging 4-Phase switched reluctance motor drive with reduced current sensors for electric vehicle application

Abstract

The paper proposes an integrated power converter (IPC) with driving/charging capabilities for 4-phase switched reluctance motor (SRM) drive based electric vehicle (EV) application. With the proposed IPC, only two current sensors are employed for measuring phase currents under all operating conditions. The proposed IPC integrates three circuits. Firstly, during the SRM driving mode, the proposed IPC is utilized as an improved miller converter. Secondly, during battery charging mode, the proposed IPC is utilized as an on-board battery charger which is based on a bridgeless boost power factor correction circuit (PFCC) that incorporates two DC-DC boost converters. The on-board battery charger is realized by utilizing the existing power electronic switches in the proposed IPC and all the phase windings as charging inductors. Third, a front-end bidirectional DC-DC converter for maintaining voltage and current balance between IPC DC-bus and battery. During driving mode, the frontend converter boosts the battery voltage to the IPC DC bus voltage. And during regeneration/braking, the stored magnetic energy is used to charge the battery in constant-current (CC) mode via the front-end converter. During battery charging via AC grid, the bridgeless boost PFCC and the front-end converter operating in buck mode charges the battery in CC/ constantvoltage (CV) modes without stepping down the AC grid voltage. The claims of the proposed IPC are validated through simulation and experimental verifications.