CN108287295B - Power line ground fault position finding method and system - Google Patents
Power line ground fault position finding method and system Download PDFInfo
- Publication number
- CN108287295B CN108287295B CN201810083323.XA CN201810083323A CN108287295B CN 108287295 B CN108287295 B CN 108287295B CN 201810083323 A CN201810083323 A CN 201810083323A CN 108287295 B CN108287295 B CN 108287295B
- Authority
- CN
- China
- Prior art keywords
- line
- fault
- ground fault
- phase
- current
- Prior art date
- 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.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 46
- 238000012360 testing method Methods 0.000 claims abstract description 53
- 238000012545 processing Methods 0.000 claims abstract description 22
- 230000005540 biological transmission Effects 0.000 claims description 13
- 238000012544 monitoring process Methods 0.000 claims description 8
- 238000004458 analytical method Methods 0.000 claims description 7
- 230000007935 neutral effect Effects 0.000 claims description 5
- 238000007599 discharging Methods 0.000 claims description 4
- 238000012423 maintenance Methods 0.000 claims description 4
- 238000007405 data analysis Methods 0.000 claims description 3
- 230000001105 regulatory effect Effects 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 208000025274 Lightning injury Diseases 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 210000001503 joint Anatomy 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/08—Locating faults in cables, transmission lines, or networks
- G01R31/081—Locating faults in cables, transmission lines, or networks according to type of conductors
- G01R31/085—Locating faults in cables, transmission lines, or networks according to type of conductors in power transmission or distribution lines, e.g. overhead
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
- Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
- Y04S10/00—Systems supporting electrical power generation, transmission or distribution
- Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
- Y04S10/52—Outage or fault management, e.g. fault detection or location
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Locating Faults (AREA)
Abstract
The invention provides a method and a system for searching a ground fault position of a power line. The method comprises the following steps: the transformer substation acquires ground fault information, and a line with a power line ground fault in the substation and a ground fault phase in a three-phase line are determined according to the acquired ground fault information; and sequentially opening the circuit breakers of all the user incoming line switch cabinets of the determined faulty line and judging whether the in-station earth fault disappears. If the fault disappears, the line equipment with the ground fault position below the user incoming line switch cabinet breaker is determined, and the process is finished. If the fault position is not disappeared, determining that the fault position is in the main circuit or the user T-connection circuit of the main circuit, and further testing and finding out the ground fault position. The system comprises a ground fault information acquisition device, a fault line and fault phase determining device, an analog current transmitting device, a field current testing device and an information data processing device. The invention is simple and easy to operate, and can rapidly and effectively judge the position where the ground fault occurs.
Description
Technical Field
The invention relates to the technical field of high-voltage power line power supply fault detection, in particular to a method and a system for searching a power line ground fault position.
Background
High-voltage power lines are an important transmission mode for power supply in enterprises and public institutions and residents, and most of the power lines are supplied with power jointly by power cables and overhead lines. In high-voltage power overhead lines, single-phase earth faults of the lines often occur due to increased power load, worsening of the surrounding environment of the lines, severe weather changes such as lightning strokes, strong winds, ice and snow, more line cable "T" users, faults of user side equipment and the like. Although the ground fault searching method and the device are more, such as a small current ground line selecting device is arranged in a station, a zero sequence current of a protecting device is monitored in an alarm mode, a line ground fault indicator is arranged, and the like, the method and the device can only detect a fault line, but cannot effectively detect the ground fault position. Particularly, in a power supply system with a neutral point not grounded, single-phase grounding faults are easy to cause two-phase grounding short circuits along with the time extension, so that accidents are expanded, and the safe and reliable operation of the power supply system is endangered.
The 35kV power line of the neutral point ungrounded power grid system is mostly a single-core cable, and compared with a three-core system-package cable, the 35kV power line is widely applied due to the remarkable advantages of large current-carrying capacity and small bending radius. The neutral point is not tripped when the power line of the power grid system is in single-phase complete grounding fault, the regulation prescribes that the grounding operation is allowed to be carried out for not more than two hours, but the capacitance current is larger when some power supply systems are in single-phase grounding, the arc is not easy to extinguish when the power supply systems are in grounding, arc grounding overvoltage is generated, the grounding fault is easy to cause two-phase grounding short circuit along with the time extension, and the accident is enlarged. In order to prevent further expansion of accidents and ensure normal electricity consumption of production equipment, when a ground fault occurs in a power line, the ground fault point needs to be found out as soon as possible and overhauled in time.
Therefore, aiming at the problems of low efficiency and poor accuracy of searching the ground fault point of the power line, prolonged time of searching the ground fault line and easy expansion of faults, a method and a system for searching the ground fault point of the power line are needed to realize quick searching of the ground fault point, cut off the ground fault point as soon as possible, recover the power line supply and meet the requirement of stable production.
Disclosure of Invention
The invention aims to provide a method and a system for searching a grounding fault position of a power line, which can realize rapid searching of the grounding fault position.
In order to solve the technical problems, the invention discloses the following technical scheme:
in one aspect, a method for locating a ground fault of a power line is provided. The power line ground fault position searching method comprises the following steps:
the transformer substation acquires ground fault information, and determines which phase of a power line and a three-phase line in which the ground fault occurs in the substation is the ground fault phase according to the acquired ground fault information;
and sequentially disconnecting all the circuit breakers of the user incoming line switch cabinets of the determined line with the ground fault, checking whether the ground fault in the transformer substation is disappeared or not by disconnecting one circuit breaker of the user incoming line switch cabinet each time, if so, determining the line equipment with the fault position below the circuit breaker of the user incoming line switch cabinet which is disconnected last, and if not, determining the user T-connection line with the fault position at the main line or the main line.
The above method for searching the position of the ground fault of the power line, for the case that the user load carried by the determined line with the ground fault is the power supply of the dual-power line, further comprises, before the circuit breakers of the user incoming line switch cabinet are disconnected in sequence: and regulating the user load loop to be supplied by a fault-free power supply line in the double power supply lines.
With the above-described power line ground fault location finding method, after the step of determining that the fault location is in the main line or the subscriber T-connect line of the main line if the ground fault does not disappear, the method further includes the steps of:
disconnecting the isolating switches at the two sides of the line incoming switch cabinet of each user on the determined line with the ground fault, switching the line with the ground fault from operation to maintenance, discharging the cable line load side of the line feeding the switch cabinet with the ground fault through the ground wire, and removing the hung ground wire;
a current generator is sequentially installed between a three-phase cable line of the feed-out line switch cabinet and the ground, current sent by the current generator is adjusted to a current set value, and when the current generator is installed each time to send out the set current value, the current value on the three-phase cable line is respectively tested on the load side of an outgoing cable of the feed-out line switch cabinet, so that the situation that which line in the three-phase line is a fault phase line in the field is further confirmed;
a current generator is arranged between a ground fault phase line and the ground of the feed-out line switch cabinet, and the current sent by the current generator is adjusted to a current set value;
the method comprises the steps that current values on three-phase cable lines are respectively tested on a rod No. 1 of a determined grounding fault line, and if the current test value of one phase of line is a set current value and other two phases of lines have no current value, the power line with the fault position behind the rod No. 1 is determined; and if no current value exists in the three-phase line, determining the cable line with the fault position between the outgoing cable of the feed-out switch cabinet and the No. 1 rod.
The above-mentioned method for finding a ground fault location of a power line further includes, after the step of determining that the fault location is a line after the No. 1 pole if the current test value of one phase line is a set current value and the other two phases lines are not current values:
testing the current values on three-phase lines at the T-connection cable line of the main line where the determined ground fault line occurs, and if the current test value of one phase line is a set current value and the other two phases of lines have no current value, determining the related power equipment with the fault position before the user T-connection cable line or the user inlet side isolating switch; if the three-phase lines have no current value, determining that the fault position is on the main line between the No. 1 rod and the current T contact or on the main line after the current T contact and the user side line thereof.
In the above method for searching the ground fault position of the power line, after the step of determining that the fault position is between the number 1 pole and the current measured T junction on the main line or the main line after the current measured T junction and the user side line thereof, in the case that the main line has a plurality of user T-junction lines, the method further includes testing the current values on the three-phase line at the next user T-junction cable line and analyzing and determining the line ground fault position, and so on.
The above method for searching the ground fault position of the power line further comprises, after determining that the fault position is on the main line between the No. 1 pole and the current measured T-junction or on the main line after the current measured T-junction and the user side line thereof if no current value exists in the three-phase line test:
testing the current values on the three-phase cable lines at the positions from the terminal rod of the determined grounding fault line to the cable on the user side, and if the current test value of one phase of the cable is a set current value and the other two phases of the cable have no current value, determining the related power equipment of the fault position before the terminal rod reaches the cable on the user side or the disconnecting switch on the user side; and if no current value exists in the three-phase line, determining that the fault position is on the main line between the No. 1 rod and the terminal rod.
For the above power line ground fault location finding method, the ground fault information includes a name of the ground fault line, a fault phase, a ground type, a bus where the ground fault is located, a zero sequence voltage of the ground fault line, and a zero sequence current action value.
In another aspect, a power line ground fault location finding system is provided. The system for searching the ground fault position of the power line comprises a ground fault information acquisition device, a fault line and fault phase determination device, an analog current transmission device, a field current testing device and an information data processing device, wherein the ground fault information acquisition device is connected with the fault line and fault phase determination device, the information data processing device is respectively connected with the fault line and fault phase determination device, the analog current transmission device and the field current testing device,
the ground fault information acquisition device is used for acquiring ground fault information when a power line has a ground fault;
the fault line and fault phase determining device is used for analyzing according to the fault information acquired by the ground fault information acquisition device and determining which phase of the line and the three-phase line in which the ground fault of the power line occurs is the ground fault phase;
the analog current transmitting device is used for providing and transmitting analog output set current for the ground fault line;
the field current testing device is used for carrying out field phase-by-phase testing on the ground fault line to which the simulated fault current is added;
the information data processing device is used for analyzing information data, and analyzing, comparing and processing the field current test value from the field current testing device and the analog current transmission value from the analog current transmission device.
For the above power line ground fault location finding system, the ground fault information includes a name of the ground fault line, a fault phase, a ground type, a bus where the ground fault is located, a zero sequence voltage of the ground fault line, and a zero sequence current action value.
For the power line ground fault position searching system, the ground fault information acquisition device adopts a background monitoring microcomputer and/or a low-current ground fault line selection device.
The method and the system for searching the grounding fault position of the power line are simple and easy to operate, and the position where the grounding fault occurs can be rapidly and effectively judged, so that the searching efficiency and the accuracy of the grounding fault position of the power line are greatly improved, the power failure time is shortened, the fault hazard is reduced, the labor intensity of line inspection staff is lightened, the grounding fault point is cut off as soon as possible, the power line supply is recovered, the power supply reliability is improved, and the stable production requirement is met.
Drawings
The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. In the drawings:
FIG. 1 is a wiring test chart of a power line ground fault location finding system according to one embodiment of the present invention;
FIG. 2 is a flow chart of a method for locating a ground fault of a power line according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of a power line ground fault location finding system according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention and the corresponding drawings. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The terms first, second and the like in the description and in the claims and in the above-described figures, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the present application described herein may be implemented in other sequences than those illustrated herein.
The method and the system for searching the grounding fault position of the power line are suitable for single-phase complete grounding faults (namely metallic grounding) of the power line. The method and the system for searching the grounding fault position of the power line are used for the 35kV power line of a neutral point ungrounded power grid system, most of the cable lines of the voltage class are single-core cables, and the cable lines of the power line are the 35kV single-core cables.
Fig. 1 is a wiring test chart of a power line ground fault location finding system according to an embodiment of the present invention. As shown in fig. 1, the three-phase lines include a-phase, B-phase, and C-phase lines. The main power line output from the substation feeder switch cabinet 100 is fed to the power consumer via poles 1, 2, … … to the terminal pole, in the example shown in fig. 1, the T-tap cable line is connected to the first subscriber feeder switch cabinet 110 at pole 9 and the T-tap cable line is connected to the second subscriber feeder switch cabinet 120 at pole 10 (terminal pole).
Fig. 2 is a flowchart of a method for locating a ground fault of a power line according to an embodiment of the present invention. As shown in fig. 1 and 2, the power line ground fault location finding method of this embodiment includes the steps of:
step S1, the transformer substation collects ground fault information, and according to the collected ground fault information, which phase of a power line and a three-phase line in which the ground fault occurs in the substation is the ground fault phase is determined. The specific process is as follows:
the transformer station collects ground fault information of the power line, wherein the ground fault information can comprise the name of the ground fault line, a fault phase, a ground type, a bus where the ground fault is located, zero sequence voltage of the ground fault line and a zero sequence current action value. In the embodiment of the invention, the name of the ground fault line, the occurrence time of the ground fault, the three-phase voltage indication value of the bus where the ground fault line is located and the zero sequence current action value can be directly displayed on a background monitoring microcomputer display of the transformer substation. Additionally or alternatively, the ground fault line name, the bus where the ground is located, the zero sequence voltage of the ground fault line, and the zero sequence current action value may also be displayed by the low current ground line selection device. Thus, the ground fault information collection can be completed by adopting a background monitoring microcomputer and/or a low-current ground line selection device.
For example, through analysis, the type of fault that occurs can be determined to be a single phase complete ground fault of the power line if the collected ground fault information is such that: the secondary opening triangular winding of the PT of the bus where the grounding fault line is located generates a zero sequence voltage of 100V, and the zero sequence current action value is higher than the zero sequence current set value; in the three-phase voltage value of the bus where the grounding line is located, the grounding fault phase voltage is 0, and other normal two phases are raised to line voltages. Further, according to the collected ground fault information, it is analyzed and confirmed that a single-phase complete ground fault occurs in a certain power line, and it is possible to determine which phase in the three-phase line is the ground fault phase.
And S2, sequentially opening the circuit breakers of the line incoming switch cabinets 110 and 120 of all users on the determined ground fault line, and checking whether the ground fault in the transformer substation disappears by opening the circuit breaker of one user line incoming switch cabinet each time. If the fault is disappeared, the line equipment of which the fault position is below the finally opened user incoming line switch cabinet breaker is determined, and the process is ended. If not, determining that the fault position is in the main line or the user T-connection line of the main line, and the flow proceeds to step S3. The specific process is as follows:
sequentially disconnecting all the line-incoming side breakers of the grounding fault line, wherein each time the breaker of one line-incoming switch cabinet of the user is disconnected, close attention is paid to whether the system grounding in the transformer substation where the grounding line is located is changed or not in real time, and if the line grounding fault disappears, the line equipment of which the grounding fault position is below the breaker of the line-incoming switch cabinet of the user which is disconnected last is determined; if the ground fault still exists, the relevant power equipment of the line ground fault position before the main line of the power line or the T-connection cable of the user and the user side incoming line breaker is determined.
If the user load is dual power, before the step of disconnecting the line-in-line side circuit breakers of all users of the ground fault line in sequence, the method further comprises: and respectively carrying out loop closing adjustment on the user loads carried by the determined lines with the ground faults one by one to supply power by the other power supply lines without faults.
And S3, disconnecting the isolating switches at the two sides of each user incoming line switch cabinet 110 and 120 in the determined line with the ground fault, switching the line with the ground fault from operation to maintenance, discharging the cable line load side of the line with the ground fault fed out of the switch cabinet through the ground wire, and removing the hung ground wire. The specific process is as follows:
disconnecting the isolating switches at the two sides of the user incoming switch cabinets 110 and 120 of the fault line respectively, switching the operation of the ground fault line from maintenance, discharging the power cable fully to the ground through the ground wire at the load side of the cable line in the ground fault line outgoing switch cabinet, and then removing the hung ground wire.
Step S4, sequentially installing the current generator 101 between the three-phase cable lines of the feed-out switchgear 100 and the ground, adjusting the current sent by the current generator 101 to the current set value, and for each time the current generator 101 is installed to send out the set current value, testing the current value on the three-phase cable lines on the load side of the feed-out cable of the feed-out switchgear 100, so as to further confirm which line in the three-phase lines is the fault phase line. The current generator can be an alternating current generator, a microcomputer relay protection tester or a microcomputer protection checking instrument, or can be other current generating instruments such as a travelling lamp transformer.
Assuming that in step S1, a certain feeding-out line in the substation is determined to be a fault line and a fault phase line is determined to be an a-phase line by the background monitoring microcomputer of the substation, a lead L and a lead N of the current generator 101 are sequentially connected between the three-phase cable line and the ground of the feeding-out switch cabinet 100, and the current generated by the current generator 101 is adjusted to a current set value of, for example, 5A, the current value of each phase cable line may be measured by respectively clamping the clamp ammeter 102 shown in fig. 1 on the three-phase cable line of the feeding-out switch cabinet 100. If the clamp ammeter 102 measures a current value of 5A on one of the cable lines and at this time, no current value or a current value as small as about 0.1A is measured on the other two-phase cable lines, it indicates that the phase line connected to the current generator 101 is a fault phase line, i.e., an a-phase line. If the clamp ammeter 102 measures zero current values of the three-phase cable lines, it indicates that the current generator 101 is connected between any one of the other normal two-phase lines and ground. The lines measured by the clamp ammeter 102 are all cable lines.
The set current value outputted from the current generator 101 may be set to 5A, or may be set to another suitable current value such as 3A or 10A.
In step S5, a current generator 101 is installed between the ground fault phase line of the feed-out switchgear 100 and ground, and the current generated by the current generator 101 is adjusted to a current set value. The specific process is as follows:
the back door of the ground fault line feed-out line switch cabinet 100 is opened, the lead L and the lead N of the current generator 101 are respectively connected between the ground fault phase cable joint and the ground of the line feed-out line cable of the ground fault line feed-out line switch cabinet 100, the current generator is adjusted to output a certain set current value, for example, an alternating current value of 5A, is added between the ground fault phase cable terminal joint and the ground, and is always output, and the following test is performed.
And S6, testing the current values on the three-phase cable lines at the rod 1 of the determined ground fault line respectively. If the current test value of one phase line is the set current value and the other two phases lines have no current value, the line with the fault position behind the No. 1 bar is determined, and the flow proceeds to step S7. If none of the three-phase lines has a current value, a cable line with a fault position between the outgoing cable of the outgoing-line-feeding switch cabinet 100 and the rod No. 1 is determined, and the flow is ended. The specific process is as follows:
taking the current set value as 5A as an example, the clamp ammeter 102 is used for testing and recording the current value on the three-phase cable line at the rod 1 of the determined ground fault line. If the measured current value of one phase cable has a current value of 5A and the other two phases cable have no current value, determining a power line with the line ground fault position behind the No. 1 rod through comparison and analysis; if no current value is measured on all three phase cabling, cabling is determined where the line ground fault is between the outgoing cable of the feeder switch cabinet 100 and rod number 1.
And S7, testing the current values of the three-phase cable lines at all the T-joint cable lines of the main line of the determined ground fault line respectively. If the current value of one phase of the lines is the set current value and the other two phases of the lines have no current value, determining that the fault position is the relevant power equipment before the user connects the cable line or the user enters the user side isolating switch, and ending the flow. If none of the three-phase lines has a current value, determining that the fault position is on the main line between the No. 1 pole and the current T contact or on the main line and the user side line after the current T contact, and proceeding to step S8. The specific process is as follows:
taking the current set value of 5A as an example, at the T-junction subscriber line of the main line of the determined ground fault line, such as the No. 9 pole T-junction subscriber cable shown in fig. 1, the current values on the three-phase cable lines are respectively tested and recorded by using the clamp type ammeter 102. If the current value of one phase line is 5A and the other two phases of lines have no current value, determining the relevant power equipment of the line ground fault position before the user T connects the cable or the user side disconnecting switch through comparison analysis. If no current value is measured on the three-phase cable, determining that the line ground fault position is on the overhead main line between the No. 1 rod and the T junction or the power main line after the T junction and the user side line thereof. Here, the T-connection refers to that a certain user on a main power (overhead) line between the No. 1 pole and the terminal pole connects a section of line to supply power to equipment thereof through a cable or overhead line, and the section of line is called a T-connection line.
In the case of multiple T-junction lines on the main line, after the step of determining that the fault location is on the overhead main line between the number 1 pole and the currently measured T-junction or on the power main line after the currently measured T-junction and its customer side line, the method further includes testing the current values on the three-phase line at the next T-junction cable line, respectively, and analyzing to determine the line ground fault location, and so on.
In step S8, the current values on the three-phase cable lines are tested at the terminal poles (i.e. the 10-pole shown in fig. 1) to the user-side cable in the determined line where the ground fault occurs, respectively. If the current value of one phase line is the set current value and the other two phases of lines have no current value, determining the related power equipment of the fault position before the terminal rod reaches the user side cable line or the user isolating switch, and ending the flow. If the three-phase lines have no current value, determining that the fault position is on the main line between the No. 1 rod and the terminal rod, and ending the flow. The specific process is as follows:
taking the current set value of 5A as an example, at the terminal pole of the determined ground fault line, i.e. the pole 10 shown in fig. 1 to the subscriber side cable, the current values on the three-phase cable line are respectively tested and recorded by using the clamp ammeter 102. If the measured current value of one phase of cable is 5A and the current values of other two phases of cables are not found, determining the relevant power equipment of the line ground fault position before the line-in-line side disconnecting switch from the terminal rod to the user-side cable line or the 10-rod user through comparison and analysis; and if no current value is measured on the three-phase cable lines, determining that the line ground fault position is on the main power overhead line between the No. 1 rod and the No. 10 rod.
Specifically, in order to improve the fault finding efficiency, the order of the ground fault finding test can be further optimized and adjusted in real time according to any one or more of the line, the load, the external environment and the fault information provided by the user in actual operation.
Fig. 3 is a schematic structural diagram of a power line ground fault location finding system according to an embodiment of the present invention. As shown in fig. 3, the power line ground fault location finding system provided by this embodiment includes a ground fault information acquisition device 31, a fault line and fault phase determination device 32, an analog current transmission device 33, a field current test device 34, and an information data processing device 35. The ground fault information collection device 31 is connected to a faulty line and faulty phase determination device 32. The information data processing device 35 is connected to the fault line and fault phase determining device 32, the analog current transmitting device 33, and the field current testing device 34, respectively.
The ground fault information collection device 31 is used for collecting ground fault information when a ground fault occurs in the power line.
The fault line and fault phase determining device 32 is configured to analyze according to the fault information collected by the ground fault information collecting device 31, and determine which phase of the line and the three-phase line where the ground fault of the power line occurs is the ground fault phase.
The analog current transmitting means 33 is for supplying and transmitting an analog output setting current for the ground fault line. The analog current transmitting device 33 may include a current generator 101, and the current generator 101 may be an ac generator, a microcomputer relay protection tester, a microcomputer protection checking instrument, or a line lamp transformer. When the line on which the ground fault occurs fails and is sufficiently discharged, a specific current value can be analog-output to the ground fault phase line by the analog current transmitting device 33, and the set current value output by the debug can be transmitted to the information data processing device 35.
The field current testing device 34 is used for performing field phase-by-phase testing on the ground fault line to which the simulated fault current is applied. When an analog current is applied to the ground fault line, the field current testing device 34 transmits the measured current value to the information data processing device 35. The field current testing device 34 may include a clamp ammeter 102.
The information data processing device 35 is used for information data analysis, and performs data analysis, comparison and processing on the field current test value from the field current testing device 34 and the analog current transmission value from the analog current transmission device 33. The data processing device may generally be a central processing unit. The data processing device 35 is connected to the fault line and fault phase determining device 32, the analog current transmitting device 33 and the field current testing device 34, respectively, and determines the ground fault position by receiving data transmitted from each device and analyzing and comparing the received data.
Specifically, the ground fault information collection device 31 collects ground fault information when a ground fault occurs in the power line. The ground fault information collection device 31 can collect the name, fault occurrence time, three-phase voltage indication value, zero-sequence voltage and zero-sequence current action value of the bus where the ground fault line is located. In the embodiment of the invention, the line name, the occurrence time of the ground fault, the three-phase voltage indication value of the bus where the ground fault line is located and the zero sequence current action value can be directly displayed on a background monitoring microcomputer display. Additionally or alternatively, the ground fault line name, the bus where the ground is located, the zero sequence voltage of the ground fault line, and the zero sequence current action value may also be displayed by the low current ground line selection device. Thus, the ground fault information collection device 31 may employ a background monitoring microcomputer and/or a low current ground line selection device. When the power line has a ground fault, the background monitoring microcomputer and/or the low-current ground line selection device transmits the collected fault information data to the fault line and fault phase determination device 32 for analysis and processing.
The working process of the power line ground fault position finding system provided by the embodiment is as follows:
when the power line has a ground fault, the ground fault information data acquisition device 31 acquires ground fault information data first; transmitting the fault information data to a fault line and fault phase determining device 32, and determining which phase of the line and the three-phase line in which the ground fault of the power line occurs is the ground fault phase by the fault line and fault phase determining device 32; transmitting an analog current to between the ground fault phase line and the ground through the analog current transmitting means 33, and transmitting the set current value outputted by the debugging to the information data processing means 35; the field current testing device 34 can perform field test on the ground fault line to which the analog current is added; the data processing device performs analysis and comparison processing on the field test current value and the analog current transmission value, and determines the position of the ground fault.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims (3)
1. A method for locating a ground fault location of a power line, the method being used for locating a single-phase complete ground fault location of the power line, and for a power line of a 35kV single-core cable of a neutral point ungrounded power grid system, the method comprising:
the transformer substation acquires ground fault information, and determines which phase of a power line and a three-phase line in which the ground fault occurs in the substation is the ground fault phase according to the acquired ground fault information;
sequentially disconnecting all the circuit breakers of the user incoming line switch cabinets of the determined line with the ground fault, checking whether the ground fault in the transformer substation is disappeared or not by disconnecting one circuit breaker of the user incoming line switch cabinet each time, if so, determining the line equipment with the fault position below the circuit breaker of the user incoming line switch cabinet which is disconnected last, and if not, determining the user T-connection line with the fault position at the main line or the main line;
for the situation that the user load carried by the determined line with the ground fault is used for supplying power to the double-power-supply line, before the circuit breakers of the user incoming line switch cabinet are sequentially disconnected, the method further comprises the following steps: the user load is closed and regulated to be supplied by a fault-free power supply line in the double power supply lines;
after the step of determining that the fault location is in the main line or the subscriber T-connect line of the main line if the ground fault does not disappear, further comprising the steps of:
disconnecting the isolating switches on the two sides of each user incoming line switch cabinet on the determined line with the ground fault, switching the line with the ground fault from operation to maintenance, discharging the cable line load side of the ground fault line outgoing line switch cabinet through the ground wire, and removing the hung ground wire;
a current generator is sequentially installed between a three-phase cable line of the feed-out line switch cabinet and the ground, current sent by the current generator is adjusted to a current set value, and when the current generator is installed each time to send out the set current value, the current value on the three-phase cable line is respectively tested on the load side of an outgoing cable of the feed-out line switch cabinet, so that the situation that which line in the three-phase line is a fault phase line in the field is further confirmed;
a current generator is arranged between a ground fault phase line and the ground of the feed-out line switch cabinet, and the current sent by the current generator is adjusted to a current set value; opening a rear door of a feed-out line switch cabinet of a ground fault line, respectively connecting a lead L and a lead N of a current generator between an outgoing line cable grounding fault phase cable joint of the feed-out line switch cabinet and the ground, and adjusting the current generator to output a set current value;
the method comprises the steps that current values on three-phase cable lines are respectively tested on a rod No. 1 of a determined grounding fault line, and if the current test value of one phase of line is a set current value and other two phases of lines have no current value, the power line with the fault position behind the rod No. 1 is determined; if no current value exists in the three-phase lines, determining a cable line with a fault position between an outgoing cable of the feed-out line switch cabinet and a No. 1 rod; the method comprises the steps that a clamp type ammeter is used for testing and recording current values on three-phase cable lines at a rod No. 1 of a determined ground fault line, and if a set current value is measured on one-phase cable and no current value is measured on other two-phase cable lines, a power line with the ground fault position behind the rod No. 1 is determined through comparison and analysis; if no current value is measured on the three-phase cable lines, determining a cable line between an outgoing cable of the outgoing-line feeding switch cabinet and a No. 1 rod at the position of the line ground fault;
after the step of determining the line having the fault position after the No. 1 bar if the current test value of one phase line is the set current value and the other two phase lines are not current values, further comprising:
testing the current values on three-phase lines at the T-connection cable line of the main line where the determined ground fault line occurs, and if the current test value of one phase line is a set current value and the other two phases of lines have no current value, determining the related power equipment with the fault position before the user T-connection cable line or the user inlet side isolating switch; if the three-phase lines have no current value, determining that the fault position is between the No. 1 rod and the current T contact point or the main line after the current T contact point and the user side line thereof;
under the condition that a plurality of user T-connection lines are arranged on the main line, after the step of determining that the fault position is between the No. 1 pole and the main line between the current measured T-junction or the main line after the current measured T-junction and the user side line thereof, respectively testing the current value on the three-phase line at the position of the next user T-connection cable line, analyzing and determining the line grounding fault position, and the like;
after the step of determining that the fault position is on the main line between the number 1 pole and the currently measured T-junction or on the main line after the currently measured T-junction and the user side line thereof if none of the three-phase line tests has a current value, the method further comprises:
testing the current values on the three-phase cable lines at the positions from the terminal rod of the determined grounding fault line to the cable on the user side, and if the current test value of one phase of the cable is a set current value and the other two phases of the cable have no current value, determining the related power equipment of the fault position before the terminal rod reaches the cable on the user side or the disconnecting switch on the user side; if no current value exists in the three-phase line, determining that the fault position is on the main line between the No. 1 rod and the terminal rod;
the ground fault information includes the name of the ground fault line, the time of occurrence of the fault, the phase of the fault, the type of ground, the bus in which the ground fault is located, the zero sequence voltage of the ground fault line, and the zero sequence current action value.
2. A search system applying the electric power line ground fault location search method according to claim 1, characterized by comprising a ground fault information acquisition means, a fault line and fault phase determination means, an analog current transmission means, a field current test means, and an information data processing means, wherein the ground fault information acquisition means is connected to the fault line and fault phase determination means, the information data processing means is connected to the fault line and fault phase determination means, the analog current transmission means, and the field current test means, respectively,
the ground fault information acquisition device is used for acquiring ground fault information when a power line has a ground fault;
the fault line and fault phase determining device is used for analyzing according to the fault information acquired by the ground fault information acquisition device and determining which phase of the line and the three-phase line in which the ground fault of the power line occurs is the ground fault phase;
the analog current transmitting device is used for providing and transmitting analog output set current for the ground fault line;
the field current testing device is used for carrying out field phase-by-phase testing on the ground fault line to which the simulated fault current is added;
the information data processing device is used for analyzing information data, and carrying out data analysis, comparison and processing on the field current test value from the field current test device and the analog current transmission value from the analog current transmission device;
the ground fault information comprises the name of a ground fault line, fault occurrence time, fault phases, a ground type, a bus where the ground fault is located, zero sequence voltage of the ground fault line and a zero sequence current action value.
3. The system according to claim 2, wherein the ground fault information acquisition device employs a background monitoring microcomputer and/or a low current ground line selection device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810083323.XA CN108287295B (en) | 2018-01-29 | 2018-01-29 | Power line ground fault position finding method and system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810083323.XA CN108287295B (en) | 2018-01-29 | 2018-01-29 | Power line ground fault position finding method and system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108287295A CN108287295A (en) | 2018-07-17 |
| CN108287295B true CN108287295B (en) | 2024-01-30 |
Family
ID=62836015
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810083323.XA Active CN108287295B (en) | 2018-01-29 | 2018-01-29 | Power line ground fault position finding method and system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108287295B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111880110B (en) * | 2019-04-15 | 2021-08-27 | 山东大学 | Single-phase earth fault disappearance judgment method and system for neutral point non-effective earthing system |
| CN110542829A (en) * | 2019-08-15 | 2019-12-06 | 贵州电网有限责任公司 | direct-current grounding judgment device and method for power distribution network below 35kV |
| CN110568316A (en) * | 2019-10-16 | 2019-12-13 | 国网四川省电力公司绵阳供电公司 | Method for quickly selecting line of ground fault of low-current grounding system |
| CN112445201B (en) * | 2020-11-19 | 2022-06-10 | 东风汽车集团有限公司 | Remote troubleshooting and fault positioning method and device |
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101303387A (en) * | 2008-04-09 | 2008-11-12 | 中国石油化工股份有限公司胜利油田分公司临盘采油厂 | Direct current injection type route selecting positioning system and method thereof |
| CN201173956Y (en) * | 2008-04-09 | 2008-12-31 | 中国石油化工股份有限公司胜利油田分公司临盘采油厂 | DC infusion type route selecting positioning system |
| CN102103179A (en) * | 2009-12-21 | 2011-06-22 | 黄洪全 | Distance-measuring and positioning method and device for failure of power transmission line |
| CN102508119A (en) * | 2011-12-09 | 2012-06-20 | 江苏镇安电力设备有限公司 | Method for positioning earth faults of parallel loop of IT (Isolation-Terre) power system |
| CN103323743A (en) * | 2013-06-10 | 2013-09-25 | 山西太钢不锈钢股份有限公司 | Method for looking up ground faults by means of integrated automation transformer substation background machine |
| CN103353573A (en) * | 2013-06-18 | 2013-10-16 | 国家电网公司 | Rapid test stopping method of power grid grounding fault |
| CN103529357A (en) * | 2013-08-02 | 2014-01-22 | 吉林省电力有限公司长春供电公司 | Method for determining section of single-phase ground fault of 10kV power distribution system |
| CN103760467A (en) * | 2014-01-27 | 2014-04-30 | 西安兴汇电力科技有限公司 | Method for inspecting single-phase earth fault point of power distribution network |
| WO2014089899A1 (en) * | 2012-12-10 | 2014-06-19 | 国家电网公司 | Distribution network phase-to-earth fault location method and location device based on transient signal wavelet transformation |
| CN104101812A (en) * | 2013-04-09 | 2014-10-15 | 北京映翰通网络技术股份有限公司 | Single-phase grounding fault detection and positioning method and system for low-current grounding power distribution network |
| CN105610137A (en) * | 2015-09-25 | 2016-05-25 | 国网山东省电力公司济南供电公司 | Centralized power-distribution-system single phase grounding fault elimination method |
| CN106771881A (en) * | 2017-01-23 | 2017-05-31 | 国网山东省电力公司德州供电公司 | The method and device of Single-phase Ground Connection Failure is positioned in star-like three-phase ungrounded power systems |
| CN106959404A (en) * | 2017-05-31 | 2017-07-18 | 山东钢铁股份有限公司 | A kind of method and system for searching power line short-circuit abort situation |
-
2018
- 2018-01-29 CN CN201810083323.XA patent/CN108287295B/en active Active
Patent Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201173956Y (en) * | 2008-04-09 | 2008-12-31 | 中国石油化工股份有限公司胜利油田分公司临盘采油厂 | DC infusion type route selecting positioning system |
| CN101303387A (en) * | 2008-04-09 | 2008-11-12 | 中国石油化工股份有限公司胜利油田分公司临盘采油厂 | Direct current injection type route selecting positioning system and method thereof |
| CN102103179A (en) * | 2009-12-21 | 2011-06-22 | 黄洪全 | Distance-measuring and positioning method and device for failure of power transmission line |
| CN102508119A (en) * | 2011-12-09 | 2012-06-20 | 江苏镇安电力设备有限公司 | Method for positioning earth faults of parallel loop of IT (Isolation-Terre) power system |
| WO2014089899A1 (en) * | 2012-12-10 | 2014-06-19 | 国家电网公司 | Distribution network phase-to-earth fault location method and location device based on transient signal wavelet transformation |
| CN104101812A (en) * | 2013-04-09 | 2014-10-15 | 北京映翰通网络技术股份有限公司 | Single-phase grounding fault detection and positioning method and system for low-current grounding power distribution network |
| CN103323743A (en) * | 2013-06-10 | 2013-09-25 | 山西太钢不锈钢股份有限公司 | Method for looking up ground faults by means of integrated automation transformer substation background machine |
| CN103353573A (en) * | 2013-06-18 | 2013-10-16 | 国家电网公司 | Rapid test stopping method of power grid grounding fault |
| CN103529357A (en) * | 2013-08-02 | 2014-01-22 | 吉林省电力有限公司长春供电公司 | Method for determining section of single-phase ground fault of 10kV power distribution system |
| CN103760467A (en) * | 2014-01-27 | 2014-04-30 | 西安兴汇电力科技有限公司 | Method for inspecting single-phase earth fault point of power distribution network |
| CN105610137A (en) * | 2015-09-25 | 2016-05-25 | 国网山东省电力公司济南供电公司 | Centralized power-distribution-system single phase grounding fault elimination method |
| CN106771881A (en) * | 2017-01-23 | 2017-05-31 | 国网山东省电力公司德州供电公司 | The method and device of Single-phase Ground Connection Failure is positioned in star-like three-phase ungrounded power systems |
| CN106959404A (en) * | 2017-05-31 | 2017-07-18 | 山东钢铁股份有限公司 | A kind of method and system for searching power line short-circuit abort situation |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108287295A (en) | 2018-07-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108287295B (en) | Power line ground fault position finding method and system | |
| US7400150B2 (en) | Remote fault monitoring in power lines | |
| US8861155B2 (en) | High-impedance fault detection and isolation system | |
| CN106950459B (en) | Distributed single-phase earth fault judgment method | |
| CN101291054B (en) | Diagnosis and protection method for residue current of ground fault in electrical power system | |
| CN108614180B (en) | Single-phase earth fault line searching method | |
| RU2583452C2 (en) | Directed detection of resistive ground fault and rupture of conductor of medium voltage | |
| CN108132425A (en) | Power grid distribution line failure on-line monitoring method and system | |
| CN108303614B (en) | 10kV cable network low-current grounding system fault positioning system and method | |
| Kasztenny et al. | Detection of incipient faults in underground medium voltage cables | |
| CN110221115B (en) | Method, device and equipment for determining single-phase grounding capacitance current | |
| CN201051663Y (en) | Single phase ground failure location device for neutral point indirect ground power grid | |
| CN106026053A (en) | Single phase earth fault positioning and isolating system and method based on low-excitation impedance transformer | |
| Hong et al. | Detection of open conductor fault using multiple measurement factors of feeder RTUs in power distribution networks with DGs | |
| Bjerkan et al. | Locating earth-faults in compensated distribution networks by means of fault indicators | |
| CN108051693A (en) | A kind of method of the raising earth fault judgment accuracy based on TAS devices | |
| Nikander et al. | Utilizing the ring operation mode of medium voltage distribution feeders | |
| JP2006220481A (en) | Method and apparatus of detecting electrostatic type high-pressure synchronous phase | |
| Velayudham et al. | Locating ground fault in distribution systems using smart meter | |
| Gudzius et al. | Characteristics of fault detection system for smart grid distribution network | |
| CN111208391A (en) | Line ground fault finder adopting alternating current and direct current signals and detection method | |
| Loukkalahti et al. | Helen Electricity Network Ltd.'s process towards high level of supply reliability | |
| RU2293342C2 (en) | METHOD FOR DETERMINING POSITION AND DISTANCE FOR ONE-PHASED GROUNDING SPOT IN ELECTRIC NETWORKS OF 6-35 kV WITH ISOLATED OR COMPENSATED NEUTRAL | |
| CN115980438A (en) | Method and system for acquiring double-bus electric energy metering voltage of transformer substation | |
| Li et al. | Research on Single-phase Grounding Fault Handling True Test of Primary and Secondary Integration Circuit Breaker |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |