Patent US5266891A successfully refreshed from Google Patents.
US5266891A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Auto self test of AC motor system
Assignee: General Electric Co
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Filing: 1990-12-20
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Granted: 1993-11-30
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Expires: 2010-12-20
Abstract
Abstract Apparatus and method for auto-self testing of a power converter and motor system wherein the power converter has three parallel legs, each including two series connected gate-turn-off thyristors (GTO) connected between a pair of DC power source buses. A microprocessor controls the test sequence in which each GTO is individually turned on in a predetermined order so as to create a transient snubber current through the motor and through each GTO when it is turned on. The snubber current and a voltage in each leg is measured and compared to a respective reference to detect wiring errors, and defects in the motor, the GTOs, and other system components. Error messages are generated in response to detection of abnormalities or defects.
Inventors
- 👤 Ajith K. Kumar
- 👤 Thomas D. Stitt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:48
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/40; G01R31/42; G01R31/34; H; H02; H02H; H02H7/00; H02H7/08; H02H7/0833; H02H7/0844; H02M; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H02M7/505; H02M7/515; H02M7/521
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
139 words
An auto self test method, for testing a power converter system having at least one motor means, while the motor means is stopped, the motor means being operatively connected to the power converter system, the power converter having at least one leg, each leg having a first and second series connected control turn-off device wherein each device has a control electrode, the method comprising the steps of: selectively generating control signals for coupling to the control electrode of each device to individually render each device conductive such that transient current flows through the motor means and through the control turn-off device rendered conductive; measuring the transient current; comparing the transient current to a reference current; and generating an indication of defect in response to a substantial difference between the transient current and the reference current, and a power converter.
Claim 2
Dependent Claim
139 words
An auto self test method, for testing a power converter system having at least one motor means, while the motor means is stopped, the motor means being operatively connected to the power converter system, the power converter having at least one leg, each leg having a first and second series connected control turn-off device wherein each device has a control electrode, the method comprising the steps of: selectively generating control signals for coupling to the control electrode of each device to individually render each device conductive such that transient current flows through the motor means and through the control turn-off device rendered conductive; measuring the transient current; comparing the transient current to a reference current; and generating an indication of defect in response to a substantial difference between the transient current and the reference current, and a power converter.
Claim 3
Dependent Claim
42 words
The method of claim 1 further comprising the steps of: detecting the control signals coupled to the control electrode of a selected control turn-off device and verifying that the control signals coupled to the electrode are identical to the control signals generated.
Claim 4
Dependent Claim
61 words
The method of claim 1 further comprising the steps of: detecting the state of conduction of a selected control turn-off device and comparing the detected state of the selected control turn-off device to the control signals coupled to the control electrode of the selected control turn-off device to detect failure of the control turn-off device to respond to the control signals.
Claim 5
Dependent Claim
47 words
The method of claim 1 further comprising the steps of: measuring a voltage in at least one leg of the power converter a period of time after measuring the transient current, and comparing the measured voltage to a reference voltage to detect defects in the power converter.
Claim 6
Dependent Claim
25 words
The method of claim 1 wherein the motor means is a three-phase motor and wherein the transient current flows through each phase of the motor.
Claim 7
Dependent Claim
155 words
An auto self testing system for a power converter system, the power converter system having a power converter and motor means, operatively connected thereto, without the risk of turning on the motor means during testing, wherein the power converter includes at least one leg, each leg having a first and second series connected control turn-off device each including a control electrode, the auto self testing system comprising: means for selectively generating control signals for coupling to the control electrode of each control turn-off device so as to individually render each control turn-off device conductive such that transient current flows through the motor means and the device rendered conductive; means for measuring the transient current operatively connected to the power converter; and means for comparing the transient current to a reference current and for generating an indication of detection of a defect and response to a substantial difference between the transient current and the reference current.
Claim 8
Dependent Claim
155 words
An auto self testing system for a power converter system, the power converter system having a power converter and motor means, operatively connected thereto, without the risk of turning on the motor means during testing, wherein the power converter includes at least one leg, each leg having a first and second series connected control turn-off device each including a control electrode, the auto self testing system comprising: means for selectively generating control signals for coupling to the control electrode of each control turn-off device so as to individually render each control turn-off device conductive such that transient current flows through the motor means and the device rendered conductive; means for measuring the transient current operatively connected to the power converter; and means for comparing the transient current to a reference current and for generating an indication of detection of a defect and response to a substantial difference between the transient current and the reference current.
Claim 9
Dependent Claim
43 words
The system of claim 6 further comprising: means for detecting the control signals coupled to the control electrode of selected control turn-off devices; and means for verifying that the control signals coupled to the control electrode are identical to the control signals generated.
Claim 10
Dependent Claim
65 words
The system of claim 6 further comprising: means for detecting the state of conduction of selected control turn-off devices in the power converter; and means for comparing the detected state of the selected control turn-off devices to the control signals coupled to each respective control electrode of the selected control turn-off devices to detect failure of the control turn-off devices to respond the control signals.
Claim 11
Dependent Claim
49 words
The system of claim 6 further comprising: means for measuring a voltage in at least one leg of the power converter a period of time after the transient current is measured; and means for comprising the measured voltage to a reference voltage to detect defects in the power converter.
Claim 12
Dependent Claim
27 words
The system of claim 6 wherein each leg of the power converter comprises: a snubber circuit including a snubber capacitor in parallel with each control turn-off device.
Claim 13
Dependent Claim
20 words
The system of claim 6 wherein the means for measuring the transient current comprises: at least one current sensing circuit.
Claim 14
Dependent Claim
20 words
The system of claim 11 wherein the means for selectively generating comprises: a microprocessor for controlling generation of control signals.
Claim 15
Dependent Claim
13 words
The system of claim 6 wherein the motor means comprises an AC motor.
Claim 16
Dependent Claim
15 words
The system of claim 6 wherein the motor means comprises multiple AC motors in parallel.
Claim 17
Dependent Claim
23 words
The system of claim 13 wherein the motor comprises a three-phase motor and the transient current flows through each phase of the motor.
Claim 18
Independent Claim
155 words
A system for auto self testing a power converter, including at least one motor means, operatively connected to the power converter, without the risk of rotating the motor means during the test, the power converter including at least one leg having a first and second series connected control turn-off device each including a control electrode, the system comprising: processor means, for controlling generation of control signals and for selectively generating the control signals for coupling to the control electrode of each control turn-off device so as to individually render each control turn-off device conductive such that transient current flows through the motor means and the device rendered conductive; means for measuring the transient current operatively connected to the power converter; and means for comparing the transient current to a reference current and for generating an indication of detection of a defect and response to a substantial difference between the transient current and the reference current.
Claim 19
Independent Claim
155 words
A system for auto self testing a power converter, including at least one motor means, operatively connected to the power converter, without the risk of rotating the motor means during the test, the power converter including at least one leg having a first and second series connected control turn-off device each including a control electrode, the system comprising: processor means, for controlling generation of control signals and for selectively generating the control signals for coupling to the control electrode of each control turn-off device so as to individually render each control turn-off device conductive such that transient current flows through the motor means and the device rendered conductive; means for measuring the transient current operatively connected to the power converter; and means for comparing the transient current to a reference current and for generating an indication of detection of a defect and response to a substantial difference between the transient current and the reference current.
Claim 20
Dependent Claim
47 words
The system of claim 16 wherein the processor means further comprises: means for detecting the control signals coupled to the control electrode of selected control turn-off devices; and means for verifying that the control signals coupled to the control electrode are identical to the control signals generated.
Claim 21
Dependent Claim
69 words
The system of claim 16 wherein the processor means further comprises: means for detecting the state of conduction of selected control turn-off devices in the power converter; and means for comparing the detected state of the selected control turn-off devices to the control signals coupled to each respective control electrode of the selected control turn-off devices to detect failure of the control turn-off devices to respond the control signals.
Claim 22
Dependent Claim
53 words
The system of claim 16 wherein the processor means further comprises: means for measuring a voltage in at least one leg of the power converter a period of time after the transient current is measured; and means for comparing the measure voltage to a reference voltage to detect defects in the power converter.
Claim 23
Dependent Claim
27 words
The system of claim 16 wherein each leg of the power converter includes a snubber circuit including a snubber capacitor in parallel with each control turn-off device.
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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) | 1996-11-29 | 1997-05-31 | 1997-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-11-29 | 2001-05-31 | 2001-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-11-29 | 2005-05-31 | 2005-11-30 | $7700.00 | Window Closed / Lapsed |