Patent ID: 8909398

Claim:
A cooling system of an electric vehicle, comprising: a cooling medium circulation path in which a cooling medium is circulated to an electrically powered drive unit that drives a vehicle by electrical power; a heat exchange unit that performs exchange of heat between the cooling medium and external air; a cooling medium circulation unit that circulates the cooling medium along the cooling medium circulation path between the heat exchange unit and the electrically powered drive unit; a blower unit that blows air against the heat exchange unit; and a control unit that controls the cooling medium circulation unit and the blower unit, thus controlling cooling of the electrically powered drive, wherein the control unit: when a drive force for the vehicle provided by the electrically powered drive unit is in a first operational region, controls the cooling medium circulation unit and the blower unit in a first cooling mode; and, when the drive force for the vehicle provided by the electrically powered drive unit is in a second operational region that is higher than the first operational region, controls the cooling medium circulation unit and the blower unit in a second cooling mode that provides a higher cooling capability than that provided in the first cooling mode, and the control unit obtains a target temperature for the electrically powered drive unit at which a sum of loss generated by the electrically powered drive unit for obtaining drive force for the vehicle, and electrical power consumed by the cooling medium circulation unit and the blower unit for cooling generated heat accompanying the loss, becomes a minimum, and controls the cooling medium circulation unit and the blower unit so that a temperature of the electrically powered drive unit attains the target temperature.