ELECTRIFIED VEHICLE CONTROL OF BI-DIRECTIONAL DC/DC CONVERTER FOR HIGH VOLTAGE POWER ASSIST FROM LOW VOLTAGE SYSTEM

A vehicle and control method include a traction battery having a first nominal voltage, an auxiliary battery having a second nominal voltage, a bi-directional voltage converter configured to convert voltage between the first nominal voltage and the second nominal voltage, an electric machine powered by the traction battery and configured to provide propulsive power to the vehicle, an internal combustion engine, a plurality of electric accessories, and a controller programmed to control the DC/DC converter and the electric machine to supply power from the auxiliary battery through the DC/DC converter to the electric machine for a specified period of time in response to electric machine power demand being between a first threshold and a second threshold, and to reduce power supplied to at least one of the plurality of electric accessories in response to the electric machine power demand exceeding the second threshold.