ELECTRIC MOTOR FOR FUEL PUMP WITH IMPROVED SHUTDOWN FEATURES

• US 20090187326A1
• Filed: 01/23/2008
• Published: 07/23/2009
• Est. Priority Date: 01/23/2008
• Status: Active Grant

• Current Assignee: Hamilton Sundstrand Corporation (Rtx Corporation)
• Original Assignee: Hamilton Sundstrand Corporation (Rtx Corporation)
• Inventors: Gieras, Jacek F., Rozman, Gregory I.
• Granted Patent: US 8,209,107 B2
• Time in Patent Office: Days
• US Class Current: 701/103
• CPC Class Codes: F02M 37/08 electrically driven
• CPC Class Codes: F04B 17/03 driven by electric motors
• CPC Class Codes: F04B 49/02 Stopping, starting, unloading or idling control
• CPC Class Codes: H02P 21/0003 Control strategies in general, e.g. linear type, e.g. P, PI, PID, using robust control
• CPC Class Codes: H02P 3/18 for stopping or slowing an ac motor

Abstract

An electric motor for a fuel pump is provided with a shutdown switch positioned intermediate an inverter, and its control coil. In this location, the shutdown function can be achieved without heavy components. In another feature, when the fuel pump is shut down, a signal is sent upstream to a voltage regulator associated with a generator, such that the voltage supplied downstream by the generator can be reduced to eliminate any potential voltage spike due to the shutdown of the electric motor. The electric motor with shutdown switch enables low weight fault tolerant flux regulated machines.

Claims

1. A generator and fuel pump assembly comprising:

a generator operable to be driven to generate electricity, and supply voltage to a bus;

said bus providing voltage to an electric motor for a fuel pump; and

a shutdown signal indicating that said electric motor for said fuel pump should be shut down, and a controller for said electric motor for said fuel pump being operable to stop rotation of said electric motor for said fuel pump, and to send a reduce voltage signal back upstream to a voltage regulator for said generator to reduce the voltage sent to said bus.

2. The assembly as set forth in claim 1, wherein said electric motor for said fuel pump is provided with an inverter, said inverter receiving power from said bus, and said inverter delivering at least three phases of power to at least three windings associated with a stator for driving a rotor which is part of said electric motor.

3. The assembly as set forth in claim 2, wherein a control coil is also associated with said stator.

4. The assembly as set forth in claim 3, wherein said control coil is positioned downstream of said inverter.

5. The assembly as set forth in claim 4, wherein a shutoff switch to stop the supply of voltage to said control coil is positioned intermediate said control coil and said inverter.

6. The assembly as set forth in claim 5, wherein said shutoff switch is a semiconductor switch provided to open a circuit and stop supply of voltage to said control coil.

7. The assembly as set forth in claim 5, wherein a feedback circuit for controlling the voltage supplied to said windings also has a switch which opens when said shutdown signal is received to stop the supply of voltage to said windings.

8. The assembly as set forth in claim 1, wherein a feedback circuit for said electric motor provides a signal back to the voltage regulator that said electric motor for said fuel pump will be stopped, and said voltage regulator then reducing the voltage being supplied on to said bus.

9. A control for a fuel pump comprising:

a fuel pump having an electric motor with rotor to drive a shaft for said fuel pump;

said motor including a plurality of stator windings and a control coil;

a voltage supply for supplying voltage to said plurality of stator windings and to said control coil, and an inverter positioned intermediate said power supply, and said control and stator coils; and

a shut off switch for stopping operation of said electric motor, said shut off switch being positioned downstream of said inverter, and upstream of said control coil, and being operable to block supply of voltage to said control coil.

10. The control as set forth in claim 9, wherein a control coil is also associated with said stator.

11. The control as set forth in claim 9, wherein said shutoff switch is a semiconductor device.

12. The control as set forth in claim 9, wherein a feedback circuit for controlling the voltage supplied to said stator windings also has a switch which opens when a shutdown signal is received to stop the supply of voltage to said stator windings.

13. A generator and fuel pump assembly comprising:

a generator operable to be driven to generate electricity, and supply voltage to a bus;

said bus providing voltage to an electric motor for a fuel pump;

a shutdown signal indicating that said electric motor for said fuel pump should be shut down, and a controller for said electric motor for said fuel pump being operable to stop operation of said electric motor for said fuel pump, and to send a reduce voltage signal back upstream to a voltage regulator for said generator to reduce the voltage sent to said bus; and

said electric motor provided with an inverter receiving power from said bus, and said inverter delivering three phases of power to at least three windings associated with a stator for driving a rotor which is part of said electric motor; and

a shutoff switch to stop the supply of voltage to said control coil positioned intermediate said control coil and said inverter, and said shutdown signal opening said shutoff switch.

14. The assembly as set forth in claim 13, wherein said shutoff switch is a semiconductor device.

15. The assembly as set forth in claim 13, wherein a feedback circuit for controlling the voltage supplied to said stator windings also has a switch which opens when a shutdown signal is received to stop the supply of voltage to said stator windings.

16. The assembly as set forth in claim 13, wherein a feedback circuit for said electric motor provides a signal back to the voltage regulator for said generator that said electric motor will be stopped, and said voltage regulator then reducing the voltage being supplied to said bus.