Bidirectional Nonisolated Fast Charger Integrated in the Electric Vehicle Traction Drivetrain

Integrated chargers, where the traction inverter is used as primary charging interface, have emerged a solution for reducing cost and footprint of electric vehicle (EV) charging. This article proposes bidirectional nonisolated integrated charger topology that also provides benefits to motor lifetime reliability through reduction in bearing currents voltages. achieved by adding an EV drive: $LC$ filter per phase with common-mode (CM) voltage control; CM inductor additional leakage current filtering; contactors switch between modes; residual device satisfy standards transformerless To obtain high efficiency make small applications, variable frequency critical soft switching leveraged. Traction mode experimental validation demonstrates torque speed steps no degradation compared standard drive, decrease shaft voltages more than 90%, increase drive 0.6% at 5-kW output power. Charging shows active reactive power peak 99.4% 98.4% rated 11 kW. measured be 22 mA, which satisfies permitting operation.