Electric motor cooling apparatus
A stator core of a cooling apparatus includes: a back yoke having a cylindrical shape; a plurality of tooth portions that protrude along a radial direction from the back yoke; a plurality of slots that are formed between the tooth portions adjacent in a circumferential direction; a cooling path which is provided on the back yoke along the circumferential direction so as not to be in communication with the slot and in which a refrigerant flows; and a refrigerant supply port that is formed on the back yoke and supplies the refrigerant to the cooling path, in which the cooling path is configured to be divided into at least two portions in the circumferential direction, and the refrigerant supply port is formed on each cooling path.
1 . An electric motor cooling apparatus which is a cooling apparatus of an electric motor having a stator,
wherein the stator comprises:
a stator core; and
a coil wound around the stator core,
the stator core comprises:
a back yoke having a cylindrical shape;
a plurality of tooth portions that protrude along a radial direction from the back yoke;
a plurality of slots that are formed between the tooth portions adjacent in a circumferential direction;
a cooling path which is provided on the back yoke along the circumferential direction so as not to be in communication with the slot and in which a refrigerant flows; and
a refrigerant supply port that is formed on the back yoke and supplies the refrigerant to the cooling path,
the electric motor cooling apparatus comprises:
a pump that supplies the refrigerant to each refrigerant supply port;
a flow rate control device that controls a flow rate of the refrigerant supplied to each refrigerant supply port from the pump;
a temperature detection portion that separately detects temperatures of upper and lower portions of the stator; and
a control portion that controls the flow rate control device based on the temperature detected by the temperature detection portion and controls the flow rate of the refrigerant supplied to the refrigerant supply port,
the stator is arranged in an attitude in which a center axis line is along a horizontal direction,
the cooling path is configured to be divided in the circumferential direction and is configured to be divided into two portions at least in an upward-downward direction,
the refrigerant supply port is formed on each cooling path,
the control portion sets refrigerant flow rates of upper and lower portions to be equal to each other when a temperature difference between the temperatures of the upper and lower portions of the stator detected by the temperature detection portion is smaller than a predetermined allowable temperature difference, and
the control portion sets the refrigerant flow rate of the lower portion to be larger than the refrigerant flow rate of the upper portion when the temperature of the lower portion of the stator is higher than the temperature of the upper portion of the stator and the temperature difference between the temperatures of the upper and lower portions of the stator is larger than the predetermined allowable temperature difference.
2 . The electric motor cooling apparatus according to claim 1 ,
wherein the stator core has a fastening portion that fixes the stator core to a fixed body,
the fastening portion has a bolt insertion hole through which a bolt for fixation to the fixed body is inserted, and
the refrigerant supply port is in communication with the bolt insertion hole.
3 . The electric motor cooling apparatus according to claim 1 ,
wherein the stator is fixed to a vehicle body such that a center axis line is along a vehicle width direction, and
the electric motor cooling apparatus comprises:
an inclination detection portion that detects an inclination of the vehicle body; and
an inclination control portion that controls the flow rate control device based on the inclination detected by the inclination detection portion and controls the flow rate of the refrigerant supplied to the refrigerant supply port.