HIGH POWER-DENSITY, HIGH BACK EMF PERMANENT MAGNET MACHINE AND METHOD OF MAKING SAME

• US 20170217320A1
• Filed: 04/20/2017
• Published: 08/03/2017
• Est. Priority Date: 11/19/2010
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: EL-Refaie, Aymen Mohamed Fawzi, King, Robert Dean
• Granted Patent: US 10,946,748 B2
• Time in Patent Office: Days
• CPC Class Codes: B60K 2006/264 with outer rotor and inner stator
• CPC Class Codes: B60K 6/26 characterised by the motors or the generators
• CPC Class Codes: B60L 2210/14 Boost converters
• CPC Class Codes: B60L 2210/42 Voltage source inverters
• CPC Class Codes: B60L 3/04 Cutting off the power supply under fault conditions protective devices and circuit arrangements in general H01H; H02H
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: B60Y 2200/92 Hybrid vehicles
• CPC Class Codes: H02M 7/537 using semiconductor devices only, e.g. single switched pulse inverters
• CPC Class Codes: H02P 25/024 controlled by supply frequency
• CPC Class Codes: H02P 27/08 with pulse width modulation
• CPC Class Codes: H02P 6/14 Electronic commutators
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y10S 903/906 Motor or generator
• CPC Class Codes: Y10T 29/49002 Electrical device making

Abstract

An electric drive system includes a permanent magnet machine having a rotor and a stator and a power converter electrically coupled to the permanent magnet machine and configured to convert a DC link voltage to an AC output voltage to drive the permanent magnet machine. The power converter includes a plurality of silicon carbide switching devices having a voltage rating that exceeds a peak line-to-line back electromotive force of the permanent magnet machine at a maximum speed of the permanent magnet machine.

Claims

1. An electric drive system comprising:

an electric machine comprising a rotor and a stator; and

a power converter electrically coupled to the electric machine and configured to convert a DC link voltage to an AC output voltage to drive the electric machine, the power converter comprising;

a plurality of silicon carbide (SiC) three-terminal controlled switching devices having a voltage rating that exceeds a peak line-to-line back electromotive force (emf) of the electric machine during an uncontrollable generation mode of the electric machine when a control gate signal on each of the switching devices is turned off.

2. The electric drive system of claim 1 wherein the plurality of switching devices comprise a plurality of SiC metal-oxide-semiconductor field effect transistors (MOSFETs).

3. The electric drive system of claim 1 wherein a maximum DC link voltage of the electric drive system is less than the voltage rating of the plurality of switching devices.

4. The electric drive system of claim 3 wherein the plurality of switching devices have a voltage rating greater than approximately three kV.

5. The electric drive system of claim 1 wherein the electric machine comprises a multi-phase permanent magnet traction motor.

6. The electric drive system of claim 1 wherein the electric machine comprises a single-phase permanent magnet traction motor.

7. The electric drive system of claim 1 wherein the electric machine comprises a multi-phase permanent magnet alternator coupled to a heat engine.

8. The electric drive system of claim 1 wherein the power converter further comprises plurality of diodes connected in an anti-parallel arrangement with the plurality of switching devices.

9. The electric drive system of claim 1 wherein the power converter is a three-phase power converter.

10. A vehicle drive system comprising:

an electric motor comprising;

a rotor; and

a stator;

a DC link; and

a power converter electrically coupled between the DC link and the electric motor to drive the electric motor;

wherein the power converter comprises a plurality of silicon carbide (SiC) three-terminal controlled switching devices having a voltage rating that exceeds a peak line-to-line back electromotive force (emf) of the motor based on a fault condition when a control gate signal one each of the switching devices is turned off.

11. The vehicle drive system of claim 10 wherein the plurality of switching devices comprise a plurality of SiC metal-oxide-semiconductor field effect transistors (MOSFETs).

12. The vehicle drive system of claim 10 wherein the plurality of switching devices have a voltage rating of at least three kV.

13. The vehicle drive system of claim 10 wherein the power converter comprises a three-phase power converter.

14. The vehicle drive system of claim 10 further comprising a voltage source coupled to the DC link and configured to provide a source voltage to the DC link.

15. The vehicle drive system of claim 14 further comprising a controller electrically coupled to the power converter, the controller configured to detect the fault condition.

16. The vehicle drive system of claim 15 further comprising at least one contactor coupled between the power source and the power converter, the contactor configured to decouple the power source from the power converter upon receiving a fault signal from the controller.

17. The vehicle drive system of claim 14 wherein the voltage source comprises a DC source and a DC-DC converter.

18. The vehicle drive system of claim 14 wherein the voltage source comprises an AC source and a rectifier.

19. The vehicle drive system of claim 10 wherein the electric motor comprises a multi-phase traction motor.

20. The vehicle drive system of claim 10 wherein the electric motor comprises a multi-phase permanent magnet alternator coupled to a heat engine.