Temperature controlled heat exchanger bypass for an electric motor

A method of bypassing a heat exchanger in an oil delivery system of an electric motor system, the method comprising:

• operating in a low-temperature mode, bypassing the heat exchanger, while an oil temperature of oil is below a first predetermined temperature;
• operating in a high-temperature mode, directing oil traversing the oil delivery system through the heat exchanger while the oil temperature is above a second predetermined temperature;
• operating in an intermediate-temperature mode, partially bypassing the heat exchanger while the oil temperature is between the first predetermined temperature and the second predetermined temperature, such that an amount of oil bypassing the heat exchanger while operating in the intermediate-temperature mode is less than an amount bypassed while operating in the low-temperature mode and greater than an amount bypassed while operating in the high-temperature mode,
• wherein the oil delivery system includes an oil pump, the oil delivery system is configured to pre-heat the oil, and the oil pump is configured to change a flowrate of the oil once the oil reaches a third predetermined temperature;
• spraying the oil onto an exposed end winding of a motor stator of a motor of the electric motor system using an oil spray bar coupled to the oil delivery system;
• and
• providing the oil to an interior of the motor stator and a motor rotor of the motor using an oil tube coupled to the oil delivery system downstream of the oil spray bar, wherein the oil tube is coupled to the oil spray bar by a cover tube positioned within a cover of the electrical motor system.

A vehicle comprising:

• a vehicle body;
• an electrical motor system including
• an oil reservoir configured to hold oil therein,
• a motor,
• an oil delivery system including a heat exchanger, the oil delivery system configured to:
• operate in a low-temperature mode, bypassing the heat exchanger, while an oil temperature of the oil is below a first predetermined temperature;
• operate in a high-temperature mode, directing oil traversing the oil delivery system through the heat exchanger while the oil temperature is above a second predetermined temperature;
• and
• operate in an intermediate-temperature mode, partially bypassing the heat exchanger, while the oil temperature is between the first predetermined temperature and the second predetermined temperature, such that an amount of oil bypassing the heat exchanger while operating in the intermediate-temperature mode is less than an amount bypassed while operating in the low-temperature mode and greater than an amount bypassed while operating in the high-temperature mode;
• an oil spray bar coupled to the oil delivery system and adapted to spray the oil onto an exposed end winding of a motor stator of the motor;
• and
• an oil tube coupled to the oil delivery system downstream of the oil spray bar and adapted to provide the oil to an interior of the motor stator and a motor rotor of the motor, wherein the oil tube is coupled to the oil spray bar by a cover tube positioned within a cover of the electrical motor system;
• and
• at least one wheel coupled to the vehicle body and configured to be driven by the electrical motor system coupled to a drivetrain for the at least one wheel.