Patent US5754026A successfully refreshed from Google Patents.
US5754026A
Expired / Lapsed
US
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Induction motor control method
Assignee: Aumovio Systems Inc
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Filing: 1997-04-04
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Granted: 1998-05-19
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Expires: 2017-04-04
Abstract
Abstract The present invention provides a method for controlling an induction motor. The method comprises determining an input impedance of the motor at an operating point; determining an input electrical power to the motor at the operating point; and estimating a slip or shaft speed of the motor at the operating point from the input impedance and input electrical power.
Inventors
- 👤 Richard Joseph Hampo
- 👤 MD Abul Masrur
- 👤 John Michael Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:30
CPC Classifications
H; H02; H02P; H02P23/00; H02P23/0004
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
52 words
A method for controlling an induction motor, said method comprising: determining an input impedance of said motor at an operating point; determining an input electrical power to said motor at said operating point; and estimating a slip of said motor at said operating point from said input impedance and input electrical power.
Claim 2
Independent Claim
52 words
A method for controlling an induction motor, said method comprising: determining an input impedance of said motor at an operating point; determining an input electrical power to said motor at said operating point; and estimating a slip of said motor at said operating point from said input impedance and input electrical power.
Claim 3
Dependent Claim
32 words
A method as recited in claim 1, wherein determining an input impedance and determining an input electrical power each include using measured electrical current data from exactly one of said motor's phases.
Claim 4
Dependent Claim
31 words
A method as recited in claim 1, wherein: determining an input impedance and determining an input electrical power each include using measured electrical current data from two of said motor's phases.
Claim 5
Dependent Claim
39 words
A method as recited in claim 1, wherein: said motor is a three-phase motor; and determining an input impedance and determining an input electrical power each include using measured electrical current data from exactly two of said motor's phases.
Claim 6
Dependent Claim
41 words
A method as recited in claim 1, further comprising: estimating a shaft speed of said motor using said slip estimate; determining a commanded current and a commanded electrical speed of said motor using said estimated shaft speed and a commanded torque.
Claim 7
Dependent Claim
29 words
A method as recited in claim 1, further comprising: determining a commanded current and a commanded electrical speed of said motor using said estimated slip and a commanded torque.
Claim 8
Independent Claim
53 words
A method for controlling an induction motor, said method comprising: determining an input impedance of said motor at an operating point; determining an input electrical power to said motor at said operating point; and estimating a shaft speed of said motor at said operating point from said input impedance and input electrical power.
Claim 9
Independent Claim
53 words
A method for controlling an induction motor, said method comprising: determining an input impedance of said motor at an operating point; determining an input electrical power to said motor at said operating point; and estimating a shaft speed of said motor at said operating point from said input impedance and input electrical power.
Claim 10
Dependent Claim
32 words
A method as recited in claim 7, wherein determining an input impedance and determining an input electrical power each include using measured electrical current data from exactly one of said motor's phases.
Claim 11
Dependent Claim
31 words
A method as recited in claim 7, wherein determining an input impedance and determining an input electrical power each include using measured electrical current data from two of said motor's phases.
Claim 12
Dependent Claim
39 words
A method as recited in claim 7, wherein: said motor is a three-phase motor; and determining an input impedance and determining an input electrical power each include using measured electrical current data from exactly two of said motor's phases.
Claim 13
Dependent Claim
41 words
A method as recited in claim 7, further comprising: estimating a shaft speed of said motor using said slip estimate; determining a commanded current and a commanded electrical speed of said motor using said estimated shaft speed and a commanded torque.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-05-18 | 2001-11-17 | 2002-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-05-18 | 2005-11-17 | 2006-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-05-18 | 2009-11-17 | 2010-05-19 | $7700.00 | Window Closed / Lapsed |