GB1603333A - Creación de Inventos y Patentes con Inteligencia Artificial

GB1603333A – Apparatus and method for monitoring faults on electrical lines
– Google Patents

GB1603333A – Apparatus and method for monitoring faults on electrical lines
– Google Patents
Apparatus and method for monitoring faults on electrical lines

Download PDF
Info

Publication number
GB1603333A

GB1603333A
GB12003/78A
GB1200378A
GB1603333A
GB 1603333 A
GB1603333 A
GB 1603333A
GB 12003/78 A
GB12003/78 A
GB 12003/78A
GB 1200378 A
GB1200378 A
GB 1200378A
GB 1603333 A
GB1603333 A
GB 1603333A
Authority
GB
United Kingdom
Prior art keywords
phase
line
voltage
impedance
signal
Prior art date
1977-04-01
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)

Expired

Application number
GB12003/78A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)

BBC Brown Boveri France SA

Original Assignee
BBC Brown Boveri France SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
1977-04-01
Filing date
1978-03-28
Publication date
1981-11-25

1978-03-28
Application filed by BBC Brown Boveri France SA
filed
Critical
BBC Brown Boveri France SA

1981-11-25
Publication of GB1603333A
publication
Critical
patent/GB1603333A/en

Status
Expired
legal-status
Critical
Current

Links

Espacenet

Global Dossier

Discuss

Classifications

H—ELECTRICITY

H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER

H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS

H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection

H02H3/38—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to both voltage and current; responsive to phase angle between voltage and current

H02H3/382—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to both voltage and current; responsive to phase angle between voltage and current involving phase comparison between current and voltage or between values derived from current and voltage

Description

PATENT SPECIFICATION
Application No 12003/78 ( 22) Filed 28 March 1978 Convention Application No 4091/77 Filed I April 1977 in Switzerland (CH) Complete Specification published 25 Nov 1981
INT CL’ H 02 H 3/38 Index at acceptance H 2 K 360 410 42 Y 595 FD JR ( 54) APPARATUS AND METHOD FOR MONITORING FAULTS ON ELECTRICAL LINES ( 71) We, BBC BROWN, BOVERI & COMPANY LIMITED, of Baden, Switzerland, a Swiss Company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:-
This invention relates to a method and apparatus for monitoring an electrical polyphase a c line for faults occurring within a predetermined distance from a measuring location on the line, in which detection signals dependent on the distance between the measuring location and the fault location are formed from the line current and line voltage and are utilized to provide a trigger or trip signal.
Furthermore, the invention relates to apparatus for the performance of such method employing measuring valuereceivers for line current and line voltage for each phase to be monitored of the network system as well as a fault distancemeasuring device for the distance-selective generation of a trigger or trip signal.
One proposal for distance-selective fault monitoring of the aforementioned character is known, for instance, from Brown Boveri Mfitteilungen, 1966, Volume 53, pages 784-790, wherein electronic means detect relative phase angles between different voltage signals, partially derived by means of line simulation impedances, and such voltage signals are subjected to threshold monitoring The trigger or trip curve e g.
in the imaginary input impedance plane in this case is circular On the other hand, a relay trigger or trip curve which can be freely configured, according to the momentary protection requirements, cannot be readily realized, especially where there is used only one measuring system for each monitored phase.
Hence, it is a primary object of the present invention to provide a new and improved method of, and apparatus for, monitoring faults on electrical lines which is not associated with the aforementioned drawbacks and limitations of the prior art proposals.
Another and more specific object of the present invention aims at providing a new and improved distance-selective fault monitoring, whose trigger or trip curve in an imaginary impedance or voltage plane can be defined with comparatively simple means as a polygon having a randomly selectable arrangement of the sides of the polygon or vertices.
According to one aspect of the present invention a method for monitoring an electrical polyphase a c line for faults occurring within a predetermined distance from a measuring location on the line, comprises the steps of forming at least three impedance-image voltage signals proportional to the voltage drop across one reference impedance each, said voltage drop being generated by applying to the respective reference impedance a line current signal indicative of the line current of the phase to be monitored, the said at least three impedance-image voltage signals and their respective reference impedances defining a polygonal triggering region in the impedance plane, deriving a detection signal from each of said impedance-image voltage signals by forming the difference between a corresponding impedance-image voltage signal and a line voltage signal indicative of the line voltage of the monitored phase, deriving at least one further detection signal from at least one non-monitored phase and subjecting phasewise immediately successive ones of said detection signals to a comparison of their relative phase angles with a threshold value of at least 1800 thereby to produce a triggering signal in the event of a fault occurring within said predetermined distance.
A resonant circuit tuned to the fundamental frequency of the line voltage may be provided for at least one phase of the line system differing from the monitored COD cy m en ( 21) ( 31) ( 32) ( 33) ( 44) ( I) ( 52) ( 11) 1 603 333 2 1,603,333 phase, said resonant circuit being connected with the related line voltage of said one phase in a synchronised control connection and with a related line voltagemeasuring value detector to provide said further detection signal.
According to another aspect of the invention apparatus for monitoring an electrical polyphase a c line for Faults occurring within a predetermined distance from a measuring location on the line, comprises means for forming at least three impedance-image voltage signals proportional to the voltage drop across one reference impedance each, said voltage drop being generated by applying to the respective reference impedance a line current signal indicative of the line current of the phase to be monitored, the said at least three impedance-image voltage signals and their respective reference impedances, defining a polygonal triggering region in the impedance plane, means for deriving a detection signal from each of said impedance-image voltage signals by forming the difference between a corresponding impedance-image voltage signal and a line voltage signal indicative of the line voltage of the monitored phase, means for deriving at least one further detection signal from at least one nonmonitored phase, and means for subjecting phase-wise immediately successive ones of said detection signals to a comparison of their relative phase angles with a threshold value of at least 1800, thereby to produce a triggering signal in the event of a fault occurring within said predetermined distance.
The monitored phase of the line may include a line current-measuring value detector connected with a reference impedance, and a line voltage-measuring detector having an output connected to a difference forming circuit, the voltage drop across the reference impedance together with the output of the line voltagemeasuring value detector being applied to said difference forming circuit, and the means for subjecting phase-wise immediately successive ones of said detection signals for comparison of their phase angles may comprise a phase anglemonitoring device having inputs with which there are connected an output of a difference forming circuit.
In the apparatus the said further detection signal may be provided by an additional difference forming circuit and a further line voltage-measuring value detector, an output of the further line voltage-measuring value detector being connected with the additional difference forming circuit so that a phase of the line different from the monitored phase together with an output of the line voltage-measuring detector is connected with monitored phase of the additional difference forming circuit, the output of the additional difference forming circuit being connected with a further input of the phase angle monitoring device.
In the apparatus a resonant circuit tuned to the fundamental frequency of the line voltage may be provided for at least one phase of the line system differing from the monitored phase, said resonant circuit being connected with the related line voltage of said one phase in a synchronized control connection and with a related line voltage-measuring value detector to provide said further detection signal.
The contemplated reference impedances, which determine at least certain of the vertices of the trigger or trip curve, can be freely selected, thereby affording the strived for adaption of the trigger or trip range The impedance-image voltages employed for the formation of the difference signals can be obtained quite simply by applying to the impedances a current signal corresponding to the line current, and equally there can be formed the difference signal required for the phase monitoring while employing a line approximation signal The phase angle monitoring then delivers a simple criterion for the location of the fault within or without the boundary limits of the trigger or trip region in accordance with the position of the line voltage vector within or without, as the case may be, such trigger or trip region, because with a position within the trigger or trip region none of the relative phase angles reaches the boundary value of 1800, whereas externally of such regions always one of such angles is greater than 1800 A threshold value comparison thus delivers an unambiguous, distance-selective trigger or trip signal.
The invention will be better understood and objects other than those set forth above, will become apparent when consideration is given to the following detailed description thereof Such description makes reference to the annexed drawings wherein:Figure 1 is a vector diagram of known impedance-image voltages in the imaginary voltage plane U,-U, for a quadrilateral trigger or trip area having a vertex or corner point at the coordinate-null point; Figure Ia is a vector diagram of the differential signals from impedance-image voltages and from line voltage signal within the trigger or trip area according to Figure I; Figure lb is a vector diagram similar to Figure Ia, but for a line voltage signal externally of the trigger or trip area; Figure 2 is a vector diagram showing the I 1,603,333 1,603,333 relationship during reversal of the current direction in the presence of a fault; Figure 3 is a vector diagram according to the invention incorporating a replacementdifference signal derived from nonmonitored phases; Figure 4 is a vector diagram according to Figure 3, however for reversal of the current direction in the presence of a fault or short-circuit; Figure 5 is a vector diagram according to the invention with an additional image voltage derived from non-monitored phases for the formation of a related difference signal by means of the line-voltage signal; Figure 6 is a circuit diagram of fault distance-measuring equipment functioning according to the previously enumerated diagrams of Figures 3 to 5; Figure 7 is a circuit diagram of a phase angle-monitoring device with threshold monitoring for connection with the measuring apparatus shown in Figure 6; and Figure 8 respectively illustrates signal diagrams as a function of time in Figures 8 (a), Figures 8 (b) and Figures 8 (c) for explaining the function of the circuitry of Figures 6 and 7.
Referring in the First instance of Figures 1, la, lb and 2, there will be initially explained on the basis of the vector diagrams shown therein the function of the fault monitoring In Figure 1 there is shown a quadrilateral trigger or trip region having the vertices or corner points 1, 2, 3 and 4.
The vertices or corner points 2, 3 and 4 are defined by the impedance-image voltages U 2, U 3 and U 4 According to Figure Ia there is then formed with the aid of the line voltage signal U obtained by the measurement as wili be explained more fully later, the difference signals Ud 2 = U 2-UK, Udc=U,-U, and Ud 4 =U 4-UK and additionally a reference signal Udl=-UK which is incorporated into the monitoring of the relative phase angle between all of the vectors starting from the tip of the vector U, and thus determines the coordinate-null point in the form of the vertex or corner point 1 For the here assumed position of the vector tip of the vector UK within the quadrilateral trigger or trip range 1-2-3 4, Figure Ia clearly shows that none of the relative phase angles between the detection signals or phasors i e between the successive difference signals Ud 2, Ud 3, Ud, or between the additional reference signal Ud, and the neighboring difference signals Ud, and Ud, has reached the threshold value 180 This is only first then the case with a position of the vector tip of the vector UK at the boundary of the trigger or trip region I-2-3 On the other hand, with a position of the vector tip of the vector U, externally of the trigger or trip region, as shown in Figure lb, the relative phase angle between Ud 3 and Ud 4 is greater than 180 .
In the case of mutually coupled or intermeshed networks, for instance in the case of parallel lines between two busses or bus bars, it is possible, under circumstances, that in the case of a fault with reversal of the current direction i e reversal of the direction of flow of the energy or power at a measuring location, there will be simulated a fault location within the boundaries ascribed to the protective device of such measuring location This is eliminated with the contemplated fault monitoring, as will be explained more fully hereinafter, by formation of the image voltages determining the vertices as the line currentvoltage drop at the reference impedances in a manner apparent from the showing of Figure 2, because such image voltages, during reversal of the current direction, shift their phase by 1800, and thus, define the now inversely arranged trigger or trip region I-2-3 4, within which the vector U, which is not affected by the reversal of the current direction does not lie For comparison purposes the trigger region of the original current direction has been shown in broken lines in Figure 2.
In the case of a fault occurring close-up to the measuring location, the line voltage then collapses almost to null This corresponds to an equally small value of the vector UY, and renders uncertain triggering or tripping at the region of the coordinatenull point To counteract this, in accordance with the invention, there can be advantageously resorted to the embodiment of Figure 3, where a line voltage signal U, derived from another phase of a multi-phase line system or network or from a number of such other phases by suitable signal mixing or superimposing, is incorporated as a replacement-difference signal or replacement-reference signal in comparison to Figure la and Figure lb e g.
as the replacement for the signal Ud, directly into the phase angle monitoring.
The trigger region 1-2-3-4 thus contains a threshold course which is adequately spaced from the coordinate-null point, because the other phases i e, the phases differing from the momentarily monitored 1,603,333 phase, only are affected in the case of multiphase faults, and therefore, in many cases deliver a sufficiently high measuring voltage As concerns multi-phase faults, especially three-phase faults, there can be utilized so-called remember or sustaining circuits», which approximately continues the course of the line voltage prior to the occurrence of the fault for a certain time, and therefore delivers measuring voltages adequate for the formation of the signal U 5.
Also such fault monitoring is insensitive to faulty tripping or triggering operations due to reversal of the current direction, as illustrated in Figure 4, owing to the transition of the trigger or trip region 1-2-3-4 to the trigger region 1-2 ‘-3 ‘-4 ‘ by virtue of the phase reversal of the corresponding impedance-image voltages.
Another possibility in accordance with the invention for moving the trigger or trip boundary further away from the coordinatenull point contemplates deriving from the line voltage of at least one phase of the line system or network, and which phase differs from the monitored phase, and in a manner as will be explained more fully hereinafter, a voltage signal U and to form therefrom together with the’ line voltage signal U of the monitored phase a difference signal Ed, and to incorporate such into the phase angle monitoring The thus resultant configuration of the trigger or trip region has been shown in Figure 5 Here again there is afforded the possibility of continuing the line voltage signal of the non-monitored phases for the formation of the signal U, in consideration of multi-phase faults.
The phase angle monitoring occurs in accordance with the invention with a threshold monitoring of at least 180 In this way there is obtained an effective boundary of the trigger or trip region, defined by the lines extending between the vertices or corner points 1, 2, 3, 4 The phase angle monitoring in accordance with the invention can also be carried out with threshold monitoring at threshold values which are greater than 1800 In this way there are formed curved boundary line sections of the trigger region between the vertices, something useful for certain purposes.
Now the circuitry shown in Figures 6 and 7 for the performance of fault monitoring according to the aforementioned method aspects, will be seen to comprise a line voltage-measuring value receiver UMR which is connected with the monitored phase R of a three-phase line system or network R, S, T The line voltage-measuring value receiver UMR comprises a voltage converter 50 There is also provided a line current-measuring value receiver IM, likewise connected to the phase R, and comprises a current converter, generally indicated by reference character 60, having three secondary windings 65, each of which applies to a related reference impedance Z 2, Z 3 and Z 4, respectively, serving as the load a line current signal Thus, there appear at these impedances Z 2, Z 7 and Zo the previously discussed impedance-image voltages U 2, U, and U respectively, whereas there directly appears at the secondary winding 55 of the line voltagemeasuring value receiver UMR the line voltage signal U, Differential amplifiers D 2, D 3 and D, are connected in circuit with the line voltage-measuring value receiver UMR and also with the impedances Z 2, Z 3 and Z 4, respectively, delivering at their outputs A 2, A 3 and A, the aforementioned difference signals Ud 2, Ud 3 and Ud 4, respectively By means of an inverter IV, and a reversing switch Sl, which when located in a switched position opposite to that shown in Figure 6, the line voltage-measuring value receiver UMR delivers at its output A, the signal Ud,=-U i e the inverted line voltage signal Thus there are initially prepared the signals required and which are of interest for the modification of the method explained in Figures 1, la and lb.
For the modified method aspects of Figure 3 and Figure 5 the reversing switch S is shifted into the illustrated switch position The line voltage-measuring value receivers UMS and UMT, which are connected to the non-monitored phases S and T, respectively, of Figure 6, deliver to the potentiometers PS and PT adjustable voltage signal components U, and UT These voltage signal components can be superimposed in a summing amplifier SV to form the voltage signal U,=k, U,+k, UT with the adjustable coefficients k, and k, which can be set at the potentiometers PS and PT By means of a further differential amplifier D,, which with a further reversing switch 52 in the illustrated position, to thus deliver the signal U, to its subtraction or negative input, there is formed a difference signal Ud 1 =Ug-UX which appears at the output A, for introduction into the phase angle monitoring, as explained with reference to Figure 5 Upon reversing the position of the reversing switch 52 there is dispensed with the subtraction of UK so that U can be directly incorporated into the phase angle monitoring, as previously discussed in IOC 1 IC I I v 1,603,333 conjuction with Figure 3 By means of a broken line indicated inverter IV 2, shown as a modification, it is furthermore possible to form a voltage signal from the signal U.
shifted by a phase shifter Ph through 90 and corresponding to the coupled or linked voltage between the phases S and T There can be provided resonant circuits SWS and SWT which use the converter-secondary windings as resonant inductances and, as illustrated, appear in the synchronized control connection with the relevant phase voltages (by means of the transformer or converter-primary windings), for sustaining the voltage signals in the case of multi-phase fau its.
The phase angle monitoring circuit PU illustrated in Figure 7 encompasses trigger circuits TR I, TR 2, TR 3 and TR 4 connected with the amplifier outputs Al, A 2, A 3 and A 4, respectively, to form square-wave pulses corresponding to the positive halfwaves of the signals Ud, Ud 2, Ud 3 and Ud 4.
All of the square-wave pulses are superimposed by means of an OR-gate GO having four inputs 70, and the output 75 of which only then carries the logic signal » O » when none of the square-wave pulses is present, i e when there occurs a gap in the superimposing of the total train of squarewave pulses In this case a flip-flop FF, which is reset to its starting state by means of an input RS, is switched such that a subsequently connected AND-gate GU 2 is blocked, whereas when there does not occur any gap in the sequence of squarewave pulses such remains in a preparatory state.
At an input AR there is delivered an excitation signal which is produced in the usual fashion during fault detection, and which, as a function of the position of the vector tip of the vector U, within or without the trigger region, would be switched through to the trigger or trip output AS or be blocked This selection is accomplished by means of an AND-gate GU, which is prepared by the input AR by means of a timing element ZT having a slight timedelay The simultaneously energized or driven monoflop NIF having a reset time corresponding to a period of the network voltage, i e, a period of the repetition frequency of the square-wave pulse train, is connected by means of a further flip-flop F 52 for initially blocking the AND-gate GU, and switches such in accordance with the reset switching of the monoflop MF only then through to the trip output AS if up to the expiration of the reset or return switching time of the monoflop MF there has not occurred any gap in the superimposed train of square-wave pulses Moreover, the dynamic input 80 of the flip-flop FF 1, which is connected with the OR-gate GO, responds to the negative starting edge of such gap, in contrast to the shown inputs 90 and 95 of the monoflop MF and flip-flop FF,.
Now in Figure 8 (a) there shown superimposing of the square-wave pulse sequence according to the positive halfwaves of the detection signals Ud, and Ud, in the case of a phase angle of 1800 between the signals Ud, and Ud, This is the boundary case for the position of the vector tip of UK at the boundary line or extremity of the trigger or trip region The graph of the showing of Figure 8 (b), on the other hand, illustrates superimposing of the square-wave pulse sequence for the case where the position of the signal UK is within the trigger or trip region, for instance according to the showing of Figure Ia Here there does not occur any gap in the superimposed pulse train, because none of the relative phase angles of neighboring signals or square-wave pulses Ud, to Ud, has reached 1800 On the other hand, with superimposing of the signals of the squarewave pulse train according to the graph as shown in Figure 8 (c), corresponding to a position of the vector tip U, outside of the trigger or trip region, there occurs a gap, the negative starting edge of which blocks an excitation signal in the manner explained above in conjunction with the circuitry of Figure 7, whereas such, in the case of the pulse graphs of Figures 8 (a) and 8 (b), after expiration of a time interval corresponding to a network voltage period, is switchedthrough for performing a triggering or tripping operation In this way there is insured for the effectiveness of the phase angle monitoring with the circuitry PU shown in Figure 7, and equally for the entire distance-selective fault monitoring.
Basically, there also can be employed other types of known phase angle monitoring or phase angle detection.
In contrast to heretofore known equipment having an effective combination of a number of measuring systems which as a function of time operate in parallel and the fault selection first can be accomplished upon the presence of evaluation or result signals delivered by all of the measuring systems, the monitoring system of the present invention has the notable advantage of greater operational security In the case of multiple systems with possibly differently rapidly operating partial measuring systems it can happen that in the interval between preparing the different partial results there occurs a change in the operating state of the line system, so that the finally present partial results, which are to be combined with one another, are predicated upon different conditions and -under circumstances no longer are compatible with one another.
1,603,333

Claims (7)

WHAT WE CLAIM IS:-

1 A method of monitoring an electrical polyphase a c line for faults occurring within a predetermined distance from a measuring location on the line, comprising the steps of forming at least three impedance-image voltage signals proportional to the voltage drop across one reference impedance each, said voltage drop being generated by applying to the respective reference impedance a line current signal indicative of the line current of the phase to be monitored, the said at least three impedance-image voltage signals and their respective reference impedances defining a polygonal triggering region in the impedance plane, deriving a detection signal from each of said impedance-image voltage signals by forming the difference between a corresponding impedance-image voltage signal and a line voltage signal indicative of the line voltage of the monitored phase, deriving at least one further detection signal from at least one non-monitored phase and subjecting phasewise immediately successive ones of said detection signals to a comparison of their relative phase angles with a threshold value of at least 180 thereby to produce a triggering signal in the event of a fault occurring within said predetermined distance.

2 A method as claimed in Claim 1, wherein a resonant circuit tuned to the fundamental frequency of the line voltage is provided for at least one phase of the line system differing from the monitored phase, said resonant circuit being connected with the related line voltage of said one phase in a synchronized control connection and with a related line voltage-measuring value detector to provide said further detection signal.

3 Apparatus for monitoring an electrical polyphase a c line for faults occurring within a predetermined distance from a measuring location on the line, comprising means for forming at least three impedanceimage voltage signals proportional to the voltage drop across one reference impedance each, said voltage drop being generated by applying to the respective reference impedance a line current signal indicative of the line current of the phase to be monitored, the said at least three impedance-image voltage signals and their respective reference impedances defining a polygonal triggering region in the impedance plane, means for deriving a detection signal from each of said impedance-image voltage signals by forming the difference between a corresponding impedance-image voltage signal and a line voltage signal indicative of the line voltage of the monitored phase, means for deriving at least one further detection signal from at least one nonmonitored phase, and means for subjecting phase-wise immediately successive ones of said detection signals to a comparison of their relative phase angles with a threshold value of at least 1800, thereby to produce a triggering signal in the event of a fault occurring within said predetermined distance.

4 Apparatus as claimed in Claim 3, wherein the monitored phase of the line includes a line current-measuring value detector connected with a reference impedance, and a line voltage-measuring detector having an output connected to a difference forming circuit, the voltage drop across the reference impedance together with the output of the line voltagemeasuring value detector being applied to said difference forming circuit, and the means for subjecting phase-wise immediately successive ones of said detection signals for comparison of their phase angles comprises a phase anglemonitoring device having inputs with which there are connected an output of a difference forming circuit.

Apparatus as claimed in Claim 3 or Claim 4, wherein said further detection signal is provided by an additional difference forming circuit and a further line voltage-measuring value detector, an output of the further line voltage-measuring value detector being connected with the additional difference forming circuit so that a phase of the line different from the monitored phase together with an output of the line voltage-measuring detector is connected with the monitored phase of the additional difference forming circuit, the output of the additional difference forming circuit being connected with a further input of the phase angle monitoring device.

6 Apparatus as claimed in any one of Claims 3 to 5, wherein a resonant circuit tuned to the fundamental frequency of the line voltage is provided for at least one phase of the line system differing from the monitored phase, said resonant circuit being connected with the related line voltage of said one phase in a synchronized control connection and with a related line voltage-measuring value detector to provide said further detection signal.

7 A method for monitoring an electrical polyphase a c line for faults substantially as hereinbefore described with reference to Figures 3 to 8 of the accompanying drawings.
I 15 12 C 1,603,333 8 Apparatus for monitoring an electrical polyphase a c line for faults substantially as ereinbefore described with reference to Figures 3 to 8 of the accompanying drawings.
EDWARD EVANS & CO, Chancery House, 53-64 Chancery Lane, London, WC 2 A, ISD.
Agent for the Applicants.
Printed for Her Majesty’s Stationery Office, by the Courier Press, Leamington Spa 1981 Published by The Patent Office, 25 Southampton Buildings, London, WC 2 A IAY, from which copies may be obtained.

GB12003/78A
1977-04-01
1978-03-28
Apparatus and method for monitoring faults on electrical lines

Expired

GB1603333A
(en)

Applications Claiming Priority (1)

Application Number
Priority Date
Filing Date
Title

CH409177A

CH612046A5
(en)

1977-04-01
1977-04-01

Publications (1)

Publication Number
Publication Date

GB1603333A
true

GB1603333A
(en)

1981-11-25

Family
ID=4269653
Family Applications (1)

Application Number
Title
Priority Date
Filing Date

GB12003/78A
Expired

GB1603333A
(en)

1977-04-01
1978-03-28
Apparatus and method for monitoring faults on electrical lines

Country Status (18)

Country
Link

US
(1)

US4249124A
(en)

JP
(1)

JPS53123850A
(en)

AR
(1)

AR215493A1
(en)

AT
(1)

AT362011B
(en)

AU
(1)

AU517285B2
(en)

BE
(1)

BE865542A
(en)

BR
(1)

BR7802003A
(en)

CA
(1)

CA1121461A
(en)

CH
(1)

CH612046A5
(en)

DE
(1)

DE2720168A1
(en)

DK
(1)

DK142178A
(en)

ES
(1)

ES468439A1
(en)

FR
(1)

FR2386173A1
(en)

GB
(1)

GB1603333A
(en)

IT
(1)

IT1094051B
(en)

NL
(1)

NL7803375A
(en)

SE
(1)

SE443478B
(en)

YU
(2)

YU58678A
(en)

Families Citing this family (9)

* Cited by examiner, † Cited by third party

Publication number
Priority date
Publication date
Assignee
Title

CH640675A5
(en)

1978-06-01
1984-01-13
Bbc Brown Boveri & Cie

METHOD AND DEVICE FOR DETERMINING THE ERROR DIRECTION WITH REGARD TO A MEASURING PLACE ON ELECTRICAL LINES.

DK147663C
(en)

1980-12-16
1985-05-28
Phoenix Tagpag

ASPHALT LAYING MACHINE

US4667152A
(en)

1985-10-17
1987-05-19
Hayes Raymond M
Method of and system for determining locations of sources of harmonics in a power distribution network

US4803635A
(en)

1985-11-07
1989-02-07
Kabushi Kaisha Toshiba
Information data output device for electric-power systems

US4931684A
(en)

1988-12-23
1990-06-05
Westinghouse Electric Corp.
Digitally scanned extended electron source in vacuum

JPH0324458U
(en)

1989-07-17
1991-03-13

US5796258A
(en)

1997-01-30
1998-08-18
Abb Power T&D Company, Inc.
Adaptive quadrilateral characteristic distance relay

US7221140B2
(en)

2004-03-16
2007-05-22
Tyco Electronics Power Systems, Inc.
Circuit, method and system for providing one or more phase voltages from input voltages

EP2443718B1
(en)

2009-06-15
2014-04-23
ABB Technology AG
An arrangement for protecting equipment of a power system

Family Cites Families (7)

* Cited by examiner, † Cited by third party

Publication number
Priority date
Publication date
Assignee
Title

FR1436596A
(en)

1965-01-22
1966-04-29
Compteurs Comp D

Distance protection device using ultra-fast solid-state relays

DE1588532C3
(en)

1966-04-11
1975-03-06
Meidensha Electric Mfg. Co. Ltd.

Distance relay

DE1538444A1
(en)

1966-12-27
1969-10-02
Denzel Dr Ing P

Distance protection with polygonal tripping area

FR1597420A
(en)

1968-07-05
1970-06-29

US3700919A
(en)

1971-02-22
1972-10-24
Allis Chalmers Mfg Co
Phase shift detector

CA976614A
(en)

1972-10-26
1975-10-21
Canadian General Electric Company Limited
Inhibited power supplies

GB1422346A
(en)

1972-11-28
1976-01-28

1977

1977-04-01
CH
CH409177A
patent/CH612046A5/xx
not_active
IP Right Cessation

1977-05-05
DE
DE19772720168
patent/DE2720168A1/en
active
Granted

1977-07-12
FR
FR7721479A
patent/FR2386173A1/en
active
Pending

1978

1978-03-07
AT
AT162378A
patent/AT362011B/en
not_active
IP Right Cessation

1978-03-13
YU
YU00586/78A
patent/YU58678A/en
unknown

1978-03-13
YU
YU00587/78A
patent/YU58778A/en
unknown

1978-03-23
CA
CA000299627A
patent/CA1121461A/en
not_active
Expired

1978-03-24
JP
JP3401478A
patent/JPS53123850A/en
active
Granted

1978-03-27
US
US05/890,794
patent/US4249124A/en
not_active
Expired – Lifetime

1978-03-28
GB
GB12003/78A
patent/GB1603333A/en
not_active
Expired

1978-03-30
SE
SE7803624A
patent/SE443478B/en
not_active
IP Right Cessation

1978-03-30
NL
NL7803375A
patent/NL7803375A/en
not_active
Application Discontinuation

1978-03-30
DK
DK142178A
patent/DK142178A/en
not_active
IP Right Cessation

1978-03-31
ES
ES468439A
patent/ES468439A1/en
not_active
Expired

1978-03-31
BE
BE186439A
patent/BE865542A/en
unknown

1978-03-31
IT
IT21828/78A
patent/IT1094051B/en
active

1978-03-31
BR
BR7802003A
patent/BR7802003A/en
unknown

1978-03-31
AR
AR271657A
patent/AR215493A1/en
active

1978-04-03
AU
AU34728/78A
patent/AU517285B2/en
not_active
Expired

Also Published As

Publication number
Publication date

JPS6231565B2
(en)

1987-07-09

AR215493A1
(en)

1979-10-15

ES468439A1
(en)

1978-12-16

SE443478B
(en)

1986-02-24

NL7803375A
(en)

1978-10-03

FR2386173A1
(en)

1978-10-27

AU3472878A
(en)

1979-10-11

DE2720168C2
(en)

1989-01-19

CA1121461A
(en)

1982-04-06

SE7803624L
(en)

1978-10-02

AU517285B2
(en)

1981-07-23

YU58778A
(en)

1982-06-30

IT7821828D0
(en)

1978-03-31

IT1094051B
(en)

1985-07-26

ATA162378A
(en)

1980-09-15

BR7802003A
(en)

1978-12-19

DK142178A
(en)

1978-10-02

US4249124A
(en)

1981-02-03

YU58678A
(en)

1982-06-30

AT362011B
(en)

1981-04-27

BE865542A
(en)

1978-07-17

JPS53123850A
(en)

1978-10-28

CH612046A5
(en)

1979-06-29

DE2720168A1
(en)

1978-10-05

Información de contacto