Patent US4500834A successfully refreshed from Google Patents.
US4500834A
Expired / Lapsed
US
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Apparatus and method for locating the position of a fault occurring in an electric power transmission system with respect to a monitoring point
Assignee: The General Electric Company PLC
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Filing: 1982-03-29
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Granted: 1985-02-19
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Expires: 2002-03-29
Abstract
Abstract A method and apparatus for locating the position of a fault occurring in an electric power transmission system wherein an indication of the position of the fault with respect to a monitoring point is obtained from the time taken for a transient component of fault signal to travel from the monitoring point to the fault and back to the monitoring point after reflection at the fault.
Inventors
- 👤 Yu M. Ko
- 👤 Keith Cornick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:57
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/08; G01R31/081; G01R31/085; H; H02; H02H; H02H7/00; H02H7/26; H02H7/265
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
112 words
A method of locating the position of a fault occurring in an electric power transmission system with respect to a monitoring point comprising: determining the time taken for a transient component of a fault signal to travel from said monitoring point to the fault and back to said monitoring point after reflection at the fault; and comparing said time taken with the time that a transient signal would take to travel from said monitoring point to the end of a zone of the system to be protected by a protective relay equipment associated with the system and back to the monitoring point, thereby to determine whether the fault lies within said zone.
Claim 2
Independent Claim
112 words
A method of locating the position of a fault occurring in an electric power transmission system with respect to a monitoring point comprising: determining the time taken for a transient component of a fault signal to travel from said monitoring point to the fault and back to said monitoring point after reflection at the fault; and comparing said time taken with the time that a transient signal would take to travel from said monitoring point to the end of a zone of the system to be protected by a protective relay equipment associated with the system and back to the monitoring point, thereby to determine whether the fault lies within said zone.
Claim 3
Dependent Claim
21 words
A method according to claim 1 wherein said time taken commences when said transient component is reflected at said monitoring point.
Claim 4
Dependent Claim
35 words
A method according to claim 1 wherein said time taken commences when said transient component passes the monitoring point after reflection at a point on the side of the monitoring point remote from the fault.
Claim 5
Dependent Claim
27 words
A method according to claim 1 wherein said time taken is measured, thereby to provide an indication of the distance of the fault from said monitoring point.
Claim 6
Independent Claim
129 words
An apparatus for use in locating the position of a fault occurring in an electric power transmission system with respect to a monitoring point comprising: signal generating means for producing an output signal in response to the passage of a transient component of a fault signal away from said monitoring point in a given direction; and comparator means responsive to the time between successive outputs from said signal generating means to determine whether said time is less than the time that a transient signal would take to travel from said monitoring point to the end of a zone of the system to be protected by a protective relay equipment associated with the apparatus and back to the monitoring point, thereby to determine whether the fault lies within said zone.
Claim 7
Independent Claim
129 words
An apparatus for use in locating the position of a fault occurring in an electric power transmission system with respect to a monitoring point comprising: signal generating means for producing an output signal in response to the passage of a transient component of a fault signal away from said monitoring point in a given direction; and comparator means responsive to the time between successive outputs from said signal generating means to determine whether said time is less than the time that a transient signal would take to travel from said monitoring point to the end of a zone of the system to be protected by a protective relay equipment associated with the apparatus and back to the monitoring point, thereby to determine whether the fault lies within said zone.
Claim 8
Dependent Claim
28 words
An apparatus according to claim 5 including timing means for measuring said time, thereby to provide an indication of the distance of the fault from said monitoring point.
Claim 9
Dependent Claim
31 words
An apparatus according to claim 5 including a directional fault detection unit which inhibits operation of the apparatus except for faults in the direction of said zone from the monitoring unit.
Claim 10
Dependent Claim
72 words
An apparatus according to claim 5 wherein the said signal generating means comprises: means for extracting signals representing the fault components (V and I) of the system voltage and current; means for generating from said extracted signals a signal of the form V±IZ where Z is the surge impedence of the system; and differentiating means responsive to said signal of the form V±IZ to produce a pulse corresponding to said transient component.
Claim 11
Dependent Claim
109 words
An apparatus according to claim 5 wherein the said signal generating means comprises: means for extracting signals representing the fault components (V and I) of the system voltage and current; means for generating from said extracted signals a signal of the form V+IZ where Z is the surge impedance of the system; and differentiating means responsive to said signal of the form V+IZ to produce a pulse corresponding to said transient component, the apparatus further including a directional fault detection unit which inhibits operation of the apparatus unless the signal representing I and an appropriate signal of the form V+IZ both reach preset levels at substantially the same time.
Claim 12
Dependent Claim
121 words
An apparatus according to claim 5 wherein the said signal generating means comprises: means for extracting signals representing the fault components (V and I) of the system voltage and current; means for generating from said extracted signals a signal of the form V+IZ where Z is the surge impedance of the system; and differentiating means responsive to said signal of the V+IZ to produce a pulse corresponding to said transient component, the apparatus further including a directional fault detection unit which inhibits operation of the apparatus unless the appropriate signal of the form V+IZ first reaches a preset level within a time after the signal representing I first reaches a preset level equal to the wave transit time of a zone.
Claim 13
Dependent Claim
39 words
An apparatus according to claim 5 including means responsive to the occurrence of a relatively high level transient signal at the monitoring point to provide a rapid indication of a fault at a position close to the monitoring point.
Claim 14
Independent Claim
178 words
An apparatus for use in locating the position of a fault occurring in an electric power transmission system with respect to a monitoring point comprising: first signal generating means for producing an output signal in response to the passage of a transient component of a fault signal past said monitoring point in a direction towards the fault; second signal generating means for producing an output signal in response to the passage of a transient component of a fault signal past said monitoring point in a direction away from the fault; and comparator means responsive to the time between an output of the first signal generating means and the next occurrence of an output from the second signal generating means to determine whether said time is less than the time that a transient signal would take to travel from said monitoring point to the end of a zone of the system to be protected by a protective relay equipment associated with the apparatus and back to the monitoring point, thereby to determine whether the fault lies within said zone.
Claim 15
Independent Claim
178 words
An apparatus for use in locating the position of a fault occurring in an electric power transmission system with respect to a monitoring point comprising: first signal generating means for producing an output signal in response to the passage of a transient component of a fault signal past said monitoring point in a direction towards the fault; second signal generating means for producing an output signal in response to the passage of a transient component of a fault signal past said monitoring point in a direction away from the fault; and comparator means responsive to the time between an output of the first signal generating means and the next occurrence of an output from the second signal generating means to determine whether said time is less than the time that a transient signal would take to travel from said monitoring point to the end of a zone of the system to be protected by a protective relay equipment associated with the apparatus and back to the monitoring point, thereby to determine whether the fault lies within said zone.
Claim 16
Dependent Claim
28 words
An apparatus according to claim 12, including timing means for measuring said time, thereby to provide an indication of the distance of the fault from said monitoring point.
Claim 17
Dependent Claim
31 words
An apparatus according to claim 12, including a directional fault detection unit which inhibits operation of the apparatus except for faults in the direction of said zone from the monitoring unit.
Claim 18
Dependent Claim
72 words
An apparatus according to claim 12, wherein each said signal generating means comprises: means for extracting signals representing the fault components (V and I) of the system voltage and current; means for generating from said extracted signals a signal of the form V±IZ where Z is the surge impedance of the system; and differentiating means responsive to said signal of the form V±IZ to produce a pulse corresponding to said transient component.
Claim 19
Dependent Claim
109 words
An apparatus according to claim 12, wherein each said signal generating means comprises: means for extracting signals representing the fault components (V and I) of the system voltage and current; means for generating from said extracted signals a signal of the form V+IZ where Z is the surge impedance of the system; and differentiating means responsive to said signal of the form V±IZ to produce a pulse corresponding to said transient component, the apparatus further including a directional fault detection unit which inhibits operation of the apparatus unless the signal representing I and an appropriate signal of the form V±IZ both reach preset levels at substantially the same time.
Claim 20
Dependent Claim
122 words
An apparatus according to claim 12, wherein each said signal generating means comprises: means for extracting signals representing the fault components (V and I) of the system voltage and current; means for generating from said extracted signals a signal of the form V±IZ where Z is the surge impedance of the system; and differentiating means responsive to said signal of the form V±IZ to produce a pulse corresponding to said transient component, the apparatus further including a directional fault detection unit which inhibits operation of the apparatus unless the appropriate signal of the form V±IZ first reaches a preset level within a time after the signal representing I first reaches a preset level equal to the wave transit time of said zone.
Claim 21
Dependent Claim
39 words
An apparatus according to claim 12, including means responsive to the occurrence of a relatively high level transient signal at the monitoring point to provide a rapid indication of a fault at a position close to the monitoring point.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-19 | 1988-08-20 | 1989-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-19 | 1992-08-20 | 1993-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-19 | 1996-08-20 | 1997-02-19 | $7700.00 | Window Closed / Lapsed |