An integral battery charger with Power Factor Correction for electric scooter

摘要

An integral battery charger is proposed for an electric scooter with Li-Ion batteries and Interior-permanent-magnet (IPM) traction motor. The battery charger is integrated in the power hardware of the scooter, with the IPM traction drive that operates as three-phase dc-dc converter with power factor correction (PFC) capability. The control of the PFC battery charger is also integrated into the traction control code that is performed by a fixed-point DSP controller. Current-controlled and voltage-controlled battery charge are actuated according to the requirements of the battery management system (BMS), that is embedded in the battery pack. Respect to other on-board chargers, the AC current is absorbed at unitary power factor with no harmonic distortion and no particular filtering is needed since the PWM ripple is minimized by interleaving the three phases of the converter. Other type of motors are also considered (IM, SMPM) and commented. The feasibility of the integral battery charger is demonstrated on a prototype electric scooter with high voltage battery (260 V nominal).