Current-based six-step control

摘要

A vehicle powertrain includes a DC-DC converter and a controller. The DC-DC converter is coupled between a drive battery and an inverter for an electric machine. The controller is configured to transition to a current control-based six-stage inverter mode and to drive the DC-DC converter to output a voltage lower than one in response to a speed of the electric machine decreasing below a back EMF threshold speed Open circuit voltage of the drive battery.