Brushless, separately-excited, variable-speed motor and AC generator/alternator with solenoid-wound, biphase AC rotor

• US 6,252,331 B1
• Filed: 09/29/1999
• Issued: 06/26/2001
• Est. Priority Date: 09/18/1997
• Status: Expired due to Fees

• Current Assignee: Donald M. Westergren, James E. Hollopeter, James W. Mildice
• Original Assignee: Donald M. Westergren, James E. Hollopeter, James W. Mildice
• Inventors: Hollopeter, James E., Mildice, James W., Westergren, Donald M.
• Primary Examiner(s): Mullins, Burton S.
• Application Number:
  US09/407,797
• Time in Patent Office: 636 Days
• Field of Search: 310/263, 310/261, 310/168, 310/112, 310/114, 310/113, 310/179, 310/184, 310/185, 310/198, 310/195
• US Class Current: 310/263
• CPC Class Codes: H02K 19/12 characterised by the arrangement of exciting windings, e.g. for self-excitation, compounding or pole-changing
• CPC Class Codes: H02K 19/26 characterised by the arrangement of exciting windings
• CPC Class Codes: H02P 2101/30 for aircraft
• CPC Class Codes: H02P 25/024 controlled by supply frequency
• CPC Class Codes: H02P 7/2855 whereby the speed is regulated by measuring the motor speed and comparing it with a given physical value
• CPC Class Codes: H02P 9/30 using semiconductor devices

Abstract

A rotating electrical machine includes a two-phase rotor having two non-rotating solenoid-wound rotor coil assemblies and two interleaved pole assemblies. Each pole assembly is magnetically coupled to its respective coil assembly and rotates together with the machine shaft. Each pole assembly has four or more elongated pole pieces, two of which couple with one pole of a coil assembly and two of which couple with the other pole of that coil assembly. An exciter circuit independently controls the power variables provided to the rotor with respect to the stator to provide a variable-speed, variable-frequency (VSVF) motor system or VSVF generator system. The exciter energizes the solenoid-wound rotor coils with biphase AC electrical excitation, to produce a radial, rotating magnetic field at the pole pieces.

Claims

1. A rotor for use in an electromechanical machine functioning as either a motor or an alternator, the electromechanical machine having a rotatable shaft along an axis of rotation, the rotor comprising:

a first and a second phase assembly, each of the first and the second phase assembly comprising;

a cup-shaped core concentric with the rotatable shaft;

a coil disposed inside said cup-shaped core and solenoid-wound with respect to the axis of rotation to provide two coaxial poles at a single end of said cup-shaped core, said coil and cup-shaped core non-rotating and fixedly mounted within the electromechanical machine; and

two pole-piece assemblies positioned so that a magnetic field from said two coaxial poles is coupled to said two pole-piece assemblies without direct physical contact, said two pole-piece assemblies fixedly mounted to said rotatable shaft, each polepiece assembly having two or more pole pieces elongated in a direction parallel to said axis of rotation;

wherein said two or more pole pieces of said first phase assembly are interleaved with said two or more pole pieces of said second phase assembly.

2. A electromechanical machine functioning as either a motor or an alternator, said electromechanical machine mountable to a non-rotating fixture, comprising:

a stator fixedly mounted to said non-rotating fixture and concentric with an axis of rotation;

a shaft rotatable along said axis of rotation; and

a rotor having a first and a second rotor phase assembly, each rotor phase assembly comprising;

a cup-shaped core;

a coil disposed inside the cup-shaped core, the coil solenoid-wound with respect to said axis of rotation to provide two poles at a single end of said cup-shaped core, said coil and cup-shaped core non-rotating and fixedly mounted to said non-rotating fixture;

two pole assemblies fixedly mounted to and rotating with said shaft, each pole assembly of said two pole assemblies having a plurality of pole pieces, each pole piece of said plurality of pole pieces elongated in a direction parallel to said axis of rotation and magnetically coupled to at least one of said two poles of said cup-shaped core,

wherein said plurality of pole pieces of said first rotor phase assembly are interleaved with said plurality of pole pieces of said second rotor phase assembly.

3. A hybrid electric vehicle drive system, comprising:

a vehicle drive train;

an engine;

an alternator, comprising;

a stator having three-phase or other polyphase AC windings;

a shaft, mechanically coupled to said engine, said shaft aligned along an axis of rotation and rotatably mounted with respect to said stator; and

a rotor having two single-phase assemblies, each single-phase assembly having a coil, a cup-shaped core, and two pole-piece assemblies, said coil disposed inside said cup-shaped core and solenoid-wound with respect to said axis of rotation to provide two coaxial poles at a single end of said cup-shaped core, said coil and cup-shaped core fixedly mounted and non-rotating with respect to said stator, said two pole-piece assemblies fixedly mounted to and rotating with said shaft, said coil and cup-shaped core positioned adjacent to but not in physical contact with said two pole-piece assemblies to provide magnetic excitation to said two pole-piece assemblies independent of an angular orientation of said two pole piece assemblies about said axis of rotation, each of said two pole-piece assemblies having two or more pole pieces, each of said two or more pole pieces elongated in a direction parallel to said axis of rotation and having an end adjacent to and in magnetic communication with one or more of said two coaxial poles at said cup-shaped core, said two or more pole pieces of one said single-phase assembly interleaved with said two or more pole pieces of another said single-phase assembly; and

a two-phase AC rotor exciter electrically coupled to said rotor for controlling the AC output from said alternator'"'"'s stator; and

a three-phase or other polyphase AC induction, switched reluctance, or permanent magnet motor receiving electrical power directly from said alternator, and mechanically coupled to said vehicle drive train.

4. An electric vehicle drive system comprising:

a vehicle drive train;

a motor, comprising;

a stator, having direct current (DC) windings;

a shaft aligned along an axis of rotation and rotatably mounted with respect to said stator; and

a rotor having a first and a second single-phase assembly, each single-phase assembly having a coil, a cup-shaped core, and two pole assemblies, said coil disposed inside said cup-shaped core and solenoid-wound with respect to said axis of rotation to provide two coaxial poles at a single end of said cup-shaped core, said coil and cup-shaped core fixedly mounted and non-rotating with respect to said stator, said two pole assemblies fixedly mounted to said shaft, said coil and cup-shaped core positioned adjacent to but not in physical contact with said two pole assemblies to provide magnetic excitation to said two pole assemblies independent of an angular orientation of said two pole assemblies about said axis of rotation, each pole assembly having two or more pole pieces, each of said two or more pole pieces elongated in a direction parallel to said axis of rotation and having an end adjacent to and in magnetic communication with one or more of said two coaxial poles at said cup-shaped core, said two or more pole pieces of said first single-phase assembly interleaved with said two or more pole pieces of another said second single-phase assembly; and

a two-phase AC rotor exciter electrically coupled to said rotor for controlling said motor and mechanically coupled to said vehicle drive train.

5. A rotating, electromechanical, separately-excited, machine, which may function as either a motor or an alternator, comprising:

a stator;

a shaft aligned along an axis of rotation and rotatably mounted with respect to said stator; and

a rotor having two single-phase assemblies, each single-phase assembly having a coil, a cup-shaped core, and two pole piece assemblies, said coil disposed inside the cup-shaped core and solenoid-wound with respect to said axis of rotation to provide two coaxial poles at a single end of said cup-shaped core, said coil and cup-shaped core positioned so that a magnetic field from said two coaxial poles is coupled to said two pole piece assemblies to provide magnetic excitation for said two pole piece assemblies, said magnetic excitation independent of an angular orientation of said two pole piece assemblies about said axis of rotation, said coil and cup-shaped core having no direct physical contact to said two pole piece assemblies orto said shaft, said coil and cup-shaped core fixedly mounted and non-rotating with respect to said stator, said two pole piece assemblies fixedly mounted to said shaft, each of said two pole piece assemblies having two or more pole pieces, each of said two or more pole pieces elongated in a direction parallel to said axis of rotation and having an end adjacent to and in magnetic communication with one or more of said two coaxial poles at said cup-shaped core, said two or more pole pieces of one said single-phase assembly interleaved with said two or more pole pieces of another said single-phase assembly.

6. The rotating electromechanical machine claimed in claim 5, wherein said stator has single-phase windings.

7. The rotating electromechanical machine claimed in claim 5, wherein said stator has three-phase windings.

8. The rotating electromechanical machine claimed in claim 5, wherein said machine operates only as a motor, and

said machine'"'"'s stator has direct current (DC) windings.

9. The rotating electromechanical machine claimed in claim 5, wherein said machine operates only as a motor, and

said machine'"'"'s stator has a fixed magnetic field created by permanent magnets.