Electric vehicle coolant pump assembly

• US 5,529,114 A
• Filed: 06/10/1994
• Issued: 06/25/1996
• Est. Priority Date: 06/10/1994
• Status: Expired due to Term

• Current Assignee: Northrop Grumman Corporation
• Original Assignee: Northrop Grumman Corporation
• Inventors: Hall, William B., Schantz, David L. Jr., Jones, Marshall G.
• Primary Examiner(s): Gluck, Richard E.
• Application Number:
  US08/258,296
• Time in Patent Office: 746 Days
• Field of Search: 417/326, 417/313, 165/41, 165/104.33
• US Class Current: 165/41
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• CPC Class Codes: B60L 2240/36 Temperature of vehicle components or parts
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: F01P 2003/006 the liquid being oil
• CPC Class Codes: F01P 2005/125 Driving auxiliary pumps electrically
• CPC Class Codes: F01P 2050/24 Hybrid vehicles
• CPC Class Codes: F01P 2050/30 Circuit boards
• CPC Class Codes: F01P 7/164 by varying pump speed
• CPC Class Codes: H02K 11/33 Drive circuits, e.g. power electronics H02K11/38 takes precedence
• CPC Class Codes: H02K 7/14 Structural association with mechanical loads, e.g. with hand-held machine tools or fans with fan or impeller for cooling the machine H02K9/06
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles

Abstract

A coolant pump assembly for an electric vehicle includes a positive displacement pump having an inlet port, an outlet port, and a rotor, a variable-speed ac motor having a rotatable shaft mated with the rotor of the pump for rotating the rotor of the pump to circulate coolant through the inlet and outlet ports of the pump, and a motor control unit, communicating with a DC power source of the electric vehicle, for controlling the speed of the motor to provide a variable coolant flow through the electric vehicle.

Claims

1. A coolant pump assembly for an electric vehicle propulsion system, comprising:

a positive displacement pump having an inlet port, an outlet port, and a rotor;

a variable-speed ac motor having a rotatable shaft mated with the rotor of the pump for rotating the rotor of the pump to circulate coolant through the inlet and outlet ports of the pump; and

control means, communicating with a DC power source of the electric vehicle propulsion system, for controlling the speed of the motor to provide a variable coolant flow through the electric vehicle.

2. The assembly of claim 1, wherein the positive displacement pump is one of a gerotor pump, a vane pump, and a gear pump.

3. The assembly of claim 1, wherein the ac motor is one of a brushless motor, a switched-reluctance motor, and an induction motor.

4. The assembly of claim 1, further comprising a housing for containing the pump, the ac motor, and the control means.

5. The assembly of claim 4, further comprising mounting means for mounting the housing.

6. The assembly of claim 1, wherein the pump has a flow rate of at least 4 gpm and a pressure rating of at least 60 psi.

7. The assembly of claim 1, wherein the coolant is aircraft turbine oil.

8. A coolant pump assembly for an electric vehicle propulsion system, comprising:

a gerotor pump having an inlet port, an outlet port, and a rotor;

a variable-speed brushless motor having a rotatable shaft mated with the rotor of the pump for rotating the rotor of the pump to circulate coolant through the inlet and outlet ports of the pump; and

control means, communicating with a DC power source of the electric vehicle propulsion system, for controlling the speed of the motor to provide a variable coolant flow through the electric vehicle.

9. A closed-loop cooling system for cooling components of an electric vehicle propulsion system, the system comprising:

a positive displacement pump having an inlet port, an outlet port, and a rotor;

a variable-speed ac motor having a rotatable shaft mated with the rotor of the pump for rotating the rotor of the pump to circulate coolant through the inlet and outlet ports of the pump;

control means, communicating with a DC power source of the electric vehicle propulsion system, for controlling the speed of the motor to provide a variable coolant flow through the electric vehicle propulsion system;

a heat exchanger, coupled to the outlet port of the pump and the components of the electric vehicle propulsion system to be cooled, for dissipating heat transferred to the coolant by the components of the electric vehicle propulsion system; and

tubing, coupling the inlet and outlet ports of the pump to the heat exchanger and the components of the electric vehicle propulsion system to be cooled, to define a closed-loop cooling system.

10. A method for circulating coolant through a cooling system to cool components of an electric vehicle propulsion system, the cooling system comprising a positive displacement pump, a variable speed ac motor having a shaft mated to a rotor of the pump for driving the pump, and a motor control unit for controlling the speed of the motor, the method comprising:

generating a signal with the motor control unit to control the speed of the variable-speed ac motor, the signal varying the speed of the motor based on a desired flow rate of the coolant;

rotating the shaft of the variable-speed ac motor based on the signal generated by the motor control unit; and

circulating the coolant through the cooling system at the desired flow rate with the positive displacement pump, as the shaft of the motor rotates the rotor of the pump, to cool the components of the electric vehicle propulsion system.

11. The method of claim 10, further comprising the step of dissipating heat transferred to the coolant as the coolant cools the components of the electric vehicle propulsion system.