Cooling apparatus of vehicle

A cooling apparatus of a vehicle comprising:

• an engine cooling system including an engine circulation circuit, in which a heat exchanging liquid for cooling an internal combustion engine of the vehicle flows, an engine pump provided in the engine circulation circuit, and an engine radiator provided in the engine circulation circuit for cooling the heat exchanging liquid, the engine circulation circuit including an engine passage formed in the internal combustion engine;
• a device cooling system including a device circulation circuit, in which the heat exchanging liquid for cooling a device of the vehicle flows, a device pump provided in the device circulation circuit, and a device radiator provided in the device circulation circuit for cooling the heat exchanging liquid, the device circulation circuit including a device passage formed in the device, the device including at least one of a motor of the vehicle, a battery for storing electric power to be supplied to the motor, and a power control unit for controlling a supply of the electric power from the battery to the motor;
• a connection apparatus that connects the engine circulation circuit and the device circulation circuit to each other, wherein the connection apparatus is configured to connect the engine circulation circuit and the device circulation circuit to each other such that the heat exchanging liquid cooled by the device radiator is supplied to the engine passage without flowing through the device passage;
• and
• an electronic control unit for controlling activations of the engine pump, the device pump, and the connection apparatus, and
• the electronic control unit is configured to:
• activate the connection apparatus to connect the engine circulation circuit and the device circulation circuit to each other and activate both of the engine pump and the device pump when the temperature of the internal combustion engine is higher than the predetermined upper limit engine temperature while the internal combustion engine is requested to be cooled, and the device is not requested to be cooled;
• control the activations of the engine pump and the device pump so as to decrease a flow rate of the heat exchanging liquid discharged from the engine pump and increase a flow rate of the heat exchanging liquid discharged from the device pump when an engine radiator flow-out liquid temperature, which is a temperature of the heat exchanging liquid flowing out from the engine radiator, is higher than a device radiator flow-out liquid temperature, which is a temperature of the heat exchanging liquid flowing out from the device radiator, and a radiator flow-out liquid temperature difference, which is a difference of the engine radiator flow-out liquid temperature with respect to the device radiator flow-out liquid temperature, is larger than a predetermined radiator flow-out liquid temperature difference while the electronic control unit connects the engine circulation circuit and the device circulation circuit to each other and activates both of the engine pump and the device pump;
• control the activations of the engine pump and the device pump so as to increase the flow rate of the heat exchanging liquid discharged from the engine pump and decrease the flow rate of the heat exchanging liquid discharged from the device pump when the engine radiator flow-out liquid temperature is higher than the device radiator flow-out liquid temperature, and the radiator flow-out liquid temperature difference is equal to or smaller than the predetermined radiator flow-out liquid temperature difference while the electronic control unit connects the engine circulation circuit and the device circulation circuit to each other and activates both of the engine pump and the device pump;
• and
• control the activations of the engine pump and the device pump so as to increase the flow rate of the heat exchanging liquid discharged from the engine pump and decrease the flow rate of the heat exchanging liquid discharged from the device pump when the engine radiator flow-out liquid temperature is equal to or lower than the device radiator flow-out liquid temperature while the electronic control unit connects the engine circulation circuit and the device circulation circuit to each other and activates both of the engine pump and the device pump.