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Three-phase induction motor

Assignee: NEC Corp
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Filing: 1987-01-07
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Granted: —
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Expires: 2007-01-07
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Abstract

Abstract A three-phase induction motor includes winding slots (1) and a stator winding (4). The number of winding slots (1) per pole and phase is a noninteger. The stator winding (4) is a three-phase balanced winding. A pitch s of the winding satisfies s = (r - t) /r or s = r/ (r + t) (where t is an odd number and r is the order of a harmonic wave to be eliminated). The motor produces less torque ripple.

Inventors

  • 👤 Kiyokazu C/O Nec Corporation Okamoto
  • 👤 Hiroshi Nippon Electric Industry Co. Ltd. Iijima
  • 👤 Tetsuo Nippon Electric Industry Co. Ltd. Endo
  • 👤 Yukio Nippon Electric Industry Co. Ltd. Miyamoto

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-03 18:48
CPC Classifications
H; H02; H02K; H02K3/00; H02K3/04; H02K3/28

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 76 words
A three-phase induction motor characterized by: winding slots (1; 5), the number of said winding slots (1; 5) per pole and phase being a noninteger; and a stator winding (4, 8) wound as a three-phase balanced winding, a pitch s of which satisfies s = (r - t) /r or s = r/ (r + t) (where t is an odd number and r is an order of a harmonic wave (3; 7) to be eliminated).
Claim 2
Dependent Claim 76 words
A three-phase induction motor characterized by: winding slots (1; 5), the number of said winding slots (1; 5) per pole and phase being a noninteger; and a stator winding (4, 8) wound as a three-phase balanced winding, a pitch s of which satisfies s = (r - t) /r or s = r/ (r + t) (where t is an odd number and r is an order of a harmonic wave (3; 7) to be eliminated).
Claim 3
Dependent Claim 10 words
A motor according to claim 1, wherein t = 1.
Claim 4
Dependent Claim 63 words
A motor according to claim 1 or 2, wherein said motor comprises a stator, the number N of slots of which is 15 when a number ℓ of poles is 2, a number m of phases is 3, a number q of slots per pole and phase is 2.5, and the order of the harmonic wave (3; 7) to be eliminated is 5.
Claim 5
Dependent Claim 64 words
A motor according to claim 1 or 2, wherein said motor comprises a stator, a total number N of slots of which is 21 when a number ℓ of poles is 2, a number m of phases is 3, a number q of slots per pole and phase is 3.5, and the order of the harmonic wave (3; 6) to be eliminated is 7.

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