Patent US5661386A successfully refreshed from Google Patents.
US5661386A
Expired / Lapsed
US
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Method for assessing in-service motor efficiency and in-service motor/load efficiency
Assignee: Lockheed Martin Energy Systems Inc
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Filing: 1996-02-13
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Granted: 1997-08-26
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Expires: 2016-02-13
Abstract
Abstract A method and apparatus for assessing the efficiency of an in-service motor. The operating characteristics of the in-service motor are remotely measured. The operating characteristics are then applied to an equivalent circuit for electrical motors. Finally the equivalent circuit is evaluated to determine the performance characteristics of said in-service motor. Based upon the evaluation an individual is able to determine the rotor speed, power output, efficiency, and toque of the in-service motor. Additionally, an individual is able to confirm the calculations by comparing measured values with values obtained as a result of the motor equivalent circuit evaluation.
Inventors
- 👤 John D. Kueck
- 👤 Pedro J. Otaduy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:38
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/34; G01R31/343
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
76 words
A method for monitoring performance characteristics of an in-service motor, comprising the steps of: remotely measuring operating characteristics of said in-service motor; applying said operating characteristics to an equivalent circuit for electrical motors; evaluating said equivalent circuit by using the resistance of the stator to calculate the power loss from the stator to determine at least one performance characteristic of said in-service motor; and confirming the determined at least one performance characteristic of said in-service motor.
Claim 2
Independent Claim
76 words
A method for monitoring performance characteristics of an in-service motor, comprising the steps of: remotely measuring operating characteristics of said in-service motor; applying said operating characteristics to an equivalent circuit for electrical motors; evaluating said equivalent circuit by using the resistance of the stator to calculate the power loss from the stator to determine at least one performance characteristic of said in-service motor; and confirming the determined at least one performance characteristic of said in-service motor.
Claim 3
Dependent Claim
13 words
The method according to claim 1, wherein said motor is an induction motor.
Claim 4
Dependent Claim
40 words
The method according to claim 1, wherein said equivalent circuit includes at least one equivalent circuit parameter selected from the group consisting of stator resistance, stator leakage inductance, rotor resistance, rotor leakage inductance, core resistance, magnetizing inductance, and slip ratio.
Claim 5
Dependent Claim
14 words
The method according to claim 1, wherein said operating characteristics are current and voltage.
Claim 6
Dependent Claim
20 words
The method according to claim 1, wherein one of said performance characteristics is the rotor speed of said in-service motor.
Claim 7
Dependent Claim
20 words
The method according to claim 1, wherein one of said performance characteristics is the power output of said in-service motor.
Claim 8
Dependent Claim
19 words
The method according to claim 1, wherein one of said performance characteristics is the efficiency of said in-service motor.
Claim 9
Dependent Claim
19 words
The method according to claim 1, wherein one of said performance characteristics is the torque of said in-service motor.
Claim 10
Dependent Claim
20 words
The method according to claim 1, wherein one of said performance characteristics is the power factor of said in-service motor.
Claim 11
Independent Claim
84 words
An apparatus for monitoring motor performance characteristics of an in-service motor comprising: means for remotely measuring operating characteristics of said in-service motor; means for applying said operating characteristics to an ac equivalent circuit for electrical motors; means for evaluating said ac equivalent circuit by using the resistance of the stator to calculate the power loss from the stator to determine at least one performance characteristic of said in-service motor; and means for confirming the determined at least one performance characteristic of said in-service motor.
Claim 12
Independent Claim
84 words
An apparatus for monitoring motor performance characteristics of an in-service motor comprising: means for remotely measuring operating characteristics of said in-service motor; means for applying said operating characteristics to an ac equivalent circuit for electrical motors; means for evaluating said ac equivalent circuit by using the resistance of the stator to calculate the power loss from the stator to determine at least one performance characteristic of said in-service motor; and means for confirming the determined at least one performance characteristic of said in-service motor.
Claim 13
Dependent Claim
14 words
The apparatus according to claim 10, wherein said in-service motor is an induction motor.
Claim 14
Dependent Claim
14 words
The apparatus according to claim 11, wherein said operating characteristics are current and voltage.
Claim 15
Dependent Claim
60 words
The apparatus according to claim 10, including means for determining at least one equivalent circuit parameter of said in-service motor selected from the group consisting of stator resistance, stator leakage inductance, rotor resistance, rotor leakage inductance, core resistance, magnetizing inductance, and slip ratio; and further including means for applying said at least one equivalent circuit parameter to said equivalent circuit.
Claim 16
Dependent Claim
19 words
The apparatus according to claim 10, wherein one of said performance characteristics is the slip of said in-service motor.
Claim 17
Dependent Claim
20 words
The apparatus according to claim 10, wherein one of said performance characteristics is the power output of said in-service motor.
Claim 18
Dependent Claim
19 words
The apparatus according to claim 10, wherein one of said performance characteristics is the efficiency of said in-service motor.
Claim 19
Dependent Claim
19 words
The apparatus according to claim 10, wherein one of said performance characteristics is the torque of said in-service motor.
Claim 20
Dependent Claim
20 words
The apparatus according to claim 10, wherein one of said performance characteristics is the power factor of said in-service motor.
References Cited (Backward Citations)
US3434055A
Cited
US4123009A
Cited
US3989991A
Cited
US4141244A
Cited
US4300078A
Cited
US4207510A
Cited
GB2044940A
Cited
US4337427A
Cited
US4423367A
Cited
US4370098A
Cited
US4442393A
Cited
US4616179A
Cited
US4672288A
Cited
US4965513A
Cited
US4777422A
Cited
US5155797A
Cited
US4888996A
Cited
US5153506A
Cited
US5153489A
Cited
US5309089A
Cited
US5388052A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-08-25 | 2001-02-24 | 2001-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-08-25 | 2005-02-24 | 2005-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-08-25 | 2009-02-24 | 2009-08-26 | $7700.00 | Window Closed / Lapsed |