Integrated motor drive and non-isolated battery charger based on the torque cancelation in the motor

For a plug-in vehicle, the traction circuit components like electric motor, inverter, and sensors are not used during the battery charging. So there is a possibility to use them in the battery charger circuit that is called an integrated motor drive and battery charger which can be galvanically isolated or non-isolated from the grid utility. A novel integrated motor drive and non-isolated battery charger is presented and described. The drive system is based on a split-phase PM motor that has a double set of stator windings. The motor windings are reconfigured by a relay for the traction and charging operation. One important challenge to use the motor as three inductors in charger circuit is to have it in stand-still during the battery charging. Simulation and experimental results are provided to verify proper operation of the system. The results shows that the system has a good performance and the developed torque is negligible during the battery charging.