SENSORLESS ELECTRIC MACHINE

• US 20150084471A1
• Filed: 12/03/2014
• Published: 03/26/2015
• Est. Priority Date: 11/01/2012
• Status: Active Grant

• Current Assignee: Westinghouse Air Brake Technologies Corporation
• Original Assignee: General Electric Company
• Inventors: Huh, Kum Kang, Reddy, Patel Bhageerath, El-Refaie, Ayman Mohamed Fawzi, Jansen, Patrick Lee, Schultz, Roy David, Salasoo, Lembit
• Granted Patent: US 9,906,108 B2
• Time in Patent Office: Days
• US Class Current: 310/156.78
• CPC Class Codes: H02K 1/223 Rotor cores with windings and permanent magnets for additional excitation in synchronous motors or generators H02K21/042; in synchronous motors having additional short-circuited winding for starting as an asynchronous motor H02K21/46
• CPC Class Codes: H02K 1/246 Variable reluctance rotors
• CPC Class Codes: H02K 1/276 Magnets embedded in the magnetic core, e.g. interior permanent magnets [IPM]
• CPC Class Codes: H02K 21/46 Motors having additional short-circuited winding for starting as an asynchronous motor
• CPC Class Codes: H02K 29/12 using detecting coils using the machine windings as detecting coil

Abstract

An electric machine that includes a rotor core made of magnetic steel; a stator configured with stationary windings therein; openings disposed within or on the rotor core; and a rotor circuit that is configured to introduce saliency based on an orientation of part of the rotor circuit in relationship to a pole location of the electric machine, where the rotor circuit is made of a conductive, non-magnetic material. A rotor component and various embodiments of electric machines are also disclosed. The present invention has been described in terms of specific embodiment(s), and it is recognized that equivalents, alternatives, and modifications, aside from those expressly stated, are possible and within the scope of the appending claims.

Claims

1. A rotor component comprising:

a rotor circuit configured for use with one of an interior permanent magnet (IPM) machine and a synchronous reluctance machine (SRM), the rotor circuit comprising;

at least one pole circuit, wherein the at least one pole circuit are made of a conductive, non-magnetic material.

2. An electric machine comprising:

a rotor core comprising magnetic steel;

a stator configured with a plurality of stationary windings therein;

a plurality of openings disposed within or on the rotor core; and

a rotor circuit configured to introduce saliency based on an orientation of a portion of the rotor circuit in relationship to a pole location of the electric machine, said rotor circuit made of a conductive, non-magnetic material.

3. The electric machine of claim 2, further comprising a plurality of permanent magnets disposed in the plurality of openings.

4. The electric machine of claim 2, wherein the electric machine is one of an interior permanent magnet (IPM) machine, a permanent magnet (PM) assisted synchronous reluctance machine (SRM), an induction machine, and a SRM.

5. The electric machine of claim 4, the IPM machine comprising one of a single layer IPM, a multi-layer IPM, and a spoke-type IPM.

6. The electric machine of claim 2, wherein the electric machine comprises a traction motor.

7. The electric machine of claim 2, wherein the rotor circuit comprises a plurality of rotor conductors connected to a plurality of connection elements.

8. The electric machine of claim 7, wherein at least one of the plurality of rotor conductors comprise one of a rotor bar, a multi-stranded bar, a multi-stranded wire, and a litz wire.

9. The electric machine of claim 7, wherein a cross-sectional shape of the plurality of rotor conductors is contoured to fit a shape of the plurality of openings.

10. The electric machine of claim 2, wherein the rotor circuit defines a configuration of at least one of a loop, a shifted loop, a cage, a shifted cage, and combinations thereof.

11. The electric machine of claim 3, the rotor circuit comprising a plurality of rotor conductors and one or more connection elements, wherein the plurality of rotor conductors are disposed in a plurality of openings adjacent the plurality of permanent magnets.

12. The electric machine of claim 11, further wherein the plurality of rotor conductors is disposed in one of the plurality of openings.

13. The electric machine of claim 2, the rotor circuit comprising at least one pole circuit.

14. The electric machine of claim 13, wherein the at least one pole circuit comprises a plurality of pole circuits.

15. The electric machine of claim 13, wherein a quantity of the at least one pole circuit equals a quantity of poles.

16. The electric machine of claim 13, wherein a quantity of the at least one pole circuit is less than a quantity of poles.

17. The electric machine of claim 16, wherein a quantity of the at least one pole circuit is half the quantity of poles.

18. The electric machine of claim 2, further comprising a shaft configured to rotate within the electric machine.

19. The electric machine of claim 2, the rotor core further comprising a plurality of laminations.

20. The electric machine of claim 19, the plurality of openings disposed through the plurality of laminations.

21. The electric machine of claim 3, wherein the plurality of magnets and a portion of the rotor circuit are co-located in the plurality of openings.

22. The electric machine of claim 2, wherein the rotor circuit comprises a plurality of loops, wherein the plurality of loops are concentric.

23. A vehicle comprising at least one electric machine of claim 2 thereon, said electric machine configured as a traction motor;

and

a vehicle support frame connected to said electric machine.

24. The vehicle of claim 23, wherein the vehicle comprises one of an off-highway vehicle (OHV), a locomotive, a mining vehicle, and an electric-motorized railcar.

25. An electric machine comprising:

a rotor core;

a stator configured with a plurality of stationary windings therein;

a plurality of openings disposed within the rotor core; and

a rotor circuit structure comprising at least one pole circuit disposed in a predetermined location, wherein said predetermined location is in range that extends from about a q-axis to about a d-axis of the electric machine.

26. An electric machine comprising:

a rotor core;

a stator configured with a plurality of stationary windings therein;

a plurality of openings disposed within the rotor core;

a rotatable shaft therethrough; and

a rotor circuit structure comprising at least one loop or ring of a conductive, non-magnetic material, wherein said at least one loop or ring is substantially concentric about a d-axis of the electric machine.

27. An interior permanent magnet (IPM) machine comprising:

a means for converting electrical energy to rotational energy; and

a means for providing increased magnetic saliency at high frequency excitation.