Sensorless electric machine

• US 9,871,418 B2
• Filed: 12/18/2015
• Issued: 01/16/2018
• 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
• Primary Examiner(s): Truong, Thomas
• Application Number:
  US14/974,848
• Publication Number:
  US 20160105064A1
• Time in Patent Office: 760 Days
• Field of Search: 310181
• 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

A rotor component that comprises a rotor circuit configured for use with either an interior permanent magnet (IPM) machine or a synchronous reluctance machine (SRM) that includes a pole circuit made of a conductive, non-magnetic material and has a midpoint that substantially aligns with a d-axis of the IPM or SRM. An electric machine with a similar rotor component therein or having a loop or ring of a conductive, non-magnetic material that is substantially concentric about a d-axis of the electric machine.

Claims

1. A rotor component having a shifted-ring configuration, comprising:

a rotor core;

a plurality of openings disposed within the rotor core;

a plurality of permanent magnets disposed in the plurality of openings in such a way so as to define a remaining opening at each end of each of the plurality of permanent magnets; and

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 is disposed in a predetermined location, wherein said predetermined location is such that a midpoint of the least one pole circuit substantially aligns with a d-axis of the IPM or SRM, and wherein a portion of the rotor circuit structure and the plurality of permanent magnets are disposed in the same plurality of openings;

a plurality of rotor bars disposed in one or more of the plurality of remaining openings; and

a plurality of connection elements disposed in one or more of the plurality of remaining openings,

wherein rotor bars from adjacent poles are co-located in one of the plurality of remaining openings.

2. An electric machine having a shifted-ring configuration, comprising:

a rotor core;

a stator configured with a plurality of stationary windings therein;

a plurality of openings disposed within the rotor core;

a plurality of permanent magnets disposed in the plurality of openings in such a way so as to define a remaining opening at each end of each of the plurality of permanent magnets; and

a rotor circuit structure comprising at least one pole circuit including a plurality of rotor connectors inserted into the remaining opening of at each end of the permanent magnet and connected by a plurality of connection elements and disposed in a predetermined location, wherein said predetermined location is such that a midpoint of the least one pole circuit substantially aligns with a d-axis of the electric machine, and wherein rotor connectors from adjacent poles are co-located in one of the plurality of remaining openings.

3. The electric machine in claim 2, wherein the plurality of magnets are disposed in a plurality of rows.

4. An electric machine having a shifted-ring configuration comprising:

a rotor core;

a stator configured with a plurality of stationary windings therein;

a first plurality of openings disposed within the rotor core;

a plurality of magnets disposed in the first plurality of openings in such a way so as to define a remaining opening at each end of each of the plurality of permanent magnets;

a rotatable shaft therethrough; and

a rotor circuit structure comprising at least one loop or ring of a conductive, non-magnetic material and including a plurality of rotor bars disposed in one or more of the plurality of remaining openings, a plurality of connection elements disposed in one or more of the plurality of remaining openings, wherein rotor bars from adjacent poles are co-located in one of the plurality of remaining openings, and wherein said at least one loop or ring is substantially concentric about a d-axis of the electric machine, and wherein a portion of the rotor circuit structure.

5. The electric machine of claim 4, wherein the plurality of magnets are disposed in a plurality of rows.

6. The electric machine in claim 4, the rotor core further comprising a second plurality of openings.