Active Power Decoupling Strategy for Single Phase AC Charging Using a Dual Inverter Drive

The dual inverter drivetrain topology allows for the reuse of drivetrain components for charging, eliminating the need for an onboard charger. However, during single phase charging, this topology suffers from an inherent second harmonic ripple in the battery current which doubles its peak value, leading to higher losses and increased heat production in the batteries. An active power decoupling strategy is presented here, that eliminates this ripple by the addition of passive elements and a new control strategy. No additional active components are required, other than a pair of relays to connect the passive elements during charging. The strategy is validated experimentally for a 240V/32A/7.68kW charging system.