Cooling apparatus of vehicle driving system

A cooling apparatus of a vehicle driving system, comprising:

• an engine water circulation passage, through which cooing water for cooling an internal combustion engine of the vehicle driving system for driving a vehicle, flows;
• an engine radiator provided in the engine water circulation passage for cooling the cooling water by an outside air;
• a hybrid system water circulation passage, through which the cooling water for cooling a first hybrid system component and a second hybrid system component of the vehicle driving system, flows, one of the first hybrid system component and the second hybrid system component including at least one of an electric motor and a battery;
• a hybrid system radiator provided in the hybrid system water circulation passage for cooling the cooling water by the outside air;
• a connection device including a first connection water passage for connecting the engine water circulation passage to the hybrid system water circulation passage and a second connection water passage for connecting the hybrid system water circulation passage to the engine water circulation passage (20);
• and
• an electronic control unit for controlling a flow of the cooling water and an activation of the connection device,
• wherein
• the electronic control unit is configured to:
• when an engine cooling process of cooling the internal combustion engine is requested, a first hybrid system cooling process of cooling the first hybrid system component is requested, a second hybrid system cooling process of cooling the second hybrid system component is requested, and a connection condition is not satisfied,
• execute a first control for controlling:
• the activation of the connection device to disconnect the engine water circulation passage from the hybrid system water circulation passage through the first connection water passage and disconnect the hybrid system water circulation passage from the engine water circulation passage through the second connection water passage;
• the flow of the cooling water in the engine water circulation passage to cool the internal combustion engine by the cooling water cooled by the engine radiator;
• and
• the flow of the cooling water in the hybrid system water circulation passage to cool the first hybrid system component and the second hybrid system component by the cooling water cooled by the hybrid system radiator, and
• when the engine cooling process is not requested, the first hybrid system cooling process is requested, the second hybrid system cooling process is requested, and the connection condition is satisfied,
• execute a second control for controlling:
• the activation of the connection device to connect the engine water circulation passage to the hybrid system water circulation passage through the first connection water passage and connect the hybrid system water circulation passage to the engine water circulation passage through the second connection water passage;
• and
• the flow of the cooling water in the engine water circulation passage, the hybrid system water circulation passage, the first connection water passage, and the second connection water passage to cool the first hybrid system component by the cooling water cooled by the engine radiator and cool the second hybrid system component by the cooling water cooled by the hybrid system radiator, and
• the connection condition is satisfied when the engine cooling process is not requested, and the cooling water flowing into the hybrid system water circulation passage from the engine water circulation passage through the first connection water passage, can cool the first hybrid system component.