A Single-Phase Integrated Onboard Charger with a Wide Voltage Range for Plug-In Electric Vehicles

Electric vehicles (EVs) employ integrated onboard battery chargers (IOBCs), which utilize a motor drive system to construct the hardware of onboard chargers (OBCs) as the propulsion and charging process are not simultaneous. Nevertheless, the existing IOBCs use extra circuitry and additional power conversion stages to attain a wide output voltage range. Furthermore, these chargers generate a non-zero electromagnetic torque. Consequently, it necessitates auxiliary components and complex control strategies to mitigate the generated electromagnetic torque during the charging process. This paper proposes a design and control of a new bridgeless boost-buck configured IOBC with a wide output voltage range for plug-in EV battery charging applications. The detailed operation of the proposed IOBC and its control architecture are presented. A dual-loop controller that preserves the grid-side unity power factor and controls the output voltage is built with a smooth transition for a mode transition from boost and buck and vice versa to achieve a wide output voltage range. The performance of the proposed IOBC has been assessed through MATLAB simulation studies on a 6.6 kW charger. A 1.3-kW Silicon-Carbide (SiC)-based laboratory prototype has been designed and tested to demonstrate the functionality of the proposed IOBC with a wide output voltage range.