The present invention relates to an energy management system including a motor, an inverter electrically connected to the motor, a DC-DC converter electrically connected to the inverter, a first energy storage unit electrically connected to a DC link of the inverter through the DC-DC converter, a second energy storage unit coupled to the inverter, and a control unit. The control unit is configured to control the distribution of electrical power from the first energy storage unit and the second energy storage unit to the inverter in dependence upon a predetermined power threshold.