CN115248375A - Online monitoring device and method for isolating switch - Google Patents
Online monitoring device and method for isolating switch Download PDFInfo
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- CN115248375A CN115248375A CN202210698682.2A CN202210698682A CN115248375A CN 115248375 A CN115248375 A CN 115248375A CN 202210698682 A CN202210698682 A CN 202210698682A CN 115248375 A CN115248375 A CN 115248375A
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- 238000000034 method Methods 0.000 title claims abstract description 34
- 238000012806 monitoring device Methods 0.000 title claims description 18
- 230000008859 change Effects 0.000 claims abstract description 69
- 238000012544 monitoring process Methods 0.000 claims abstract description 27
- 238000005259 measurement Methods 0.000 claims description 17
- 238000004590 computer program Methods 0.000 claims description 6
- 238000004891 communication Methods 0.000 claims description 5
- 238000012545 processing Methods 0.000 claims description 4
- 238000001914 filtration Methods 0.000 claims description 3
- 230000008569 process Effects 0.000 abstract description 7
- 238000010586 diagram Methods 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 3
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
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- 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
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
- G01R31/3271—Testing of circuit interrupters, switches or circuit-breakers of high voltage or medium voltage devices
- G01R31/3272—Apparatus, systems or circuits therefor
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K13/00—Thermometers specially adapted for specific purposes
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
-
- 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
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
- G01R31/3271—Testing of circuit interrupters, switches or circuit-breakers of high voltage or medium voltage devices
- G01R31/3272—Apparatus, systems or circuits therefor
- G01R31/3274—Details related to measuring, e.g. sensing, displaying or computing; Measuring of variables related to the contact pieces, e.g. wear, position or resistance
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H9/00—Details of switching devices, not covered by groups H01H1/00 - H01H7/00
- H01H9/16—Indicators for switching condition, e.g. "on" or "off"
- H01H9/167—Circuits for remote indication
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- Keying Circuit Devices (AREA)
Abstract
The device provides a high-frequency signal for the isolating switch through a high-frequency power supply circuit, measures the resistance value of the isolating switch through a loop resistance measuring circuit to obtain a first resistance value change curve, determines a second resistance value change curve of the isolating switch by combining the contact temperature in a measuring period and a pre-stored temperature-resistance value corresponding relation, corrects the first resistance value change curve through the second resistance value change curve to finally obtain a change curve of a contact resistance, and thus, the influence of external interference on a resistance measuring result in the measuring process can be reduced, the measuring result accurately reflects the change of the contact resistance, and the reliability of fault monitoring of the isolating switch is improved.
Description
Technical Field
The application belongs to the technical field of online monitoring of electric power systems, and particularly relates to an online monitoring device and method for an isolating switch.
Background
The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.
The isolating switch is usually a high-voltage isolating switch, is used for a line with rated voltage of 1kV or more, establishes a reliable insulating gap after opening, separates equipment or the line to be overhauled from a power supply by an obvious disconnection point so as to ensure the safety of maintainers and equipment, can change the line according to the operation requirement, has a simple structure, and plays an important role in a high-voltage distribution network.
When the disconnecting switch is used for a long time, the contact resistance of a contact of the disconnecting switch is increased, the contact generates heat, and the contact can be damaged seriously, so that the transmission and distribution of electric energy and the safe and reliable operation of a system are influenced. Most of the existing on-line monitoring devices for the disconnecting switch adopt a method for measuring loop resistance to judge the contact quality of the disconnecting switch, but the on-line monitoring devices can be influenced by external environments such as rain, snow, electromagnetic interference and the like in the resistance measuring process, so that the measuring result cannot directly reflect the change of contact resistance, and the reliability of fault monitoring of the disconnecting switch is low.
Disclosure of Invention
In order to solve the problems, the application provides an on-line monitoring device and method for an isolating switch, and aims to improve the accuracy of a monitoring result of the isolating switch and enable the monitoring result to accurately reflect the change of contact resistance of a contact.
In order to achieve the above object, the present application mainly includes the following aspects:
in a first aspect, an embodiment of the present application provides an online monitoring device for a disconnecting switch, including: the temperature measuring circuit comprises a controller, a high-frequency power supply circuit, a loop resistance measuring circuit and a temperature measuring circuit;
the high-frequency power supply circuit is connected to two ends of the isolating switch and provides a high-frequency signal for the isolating switch; the loop resistance measuring circuit is used for measuring the resistance value of the isolating switch; the temperature measuring circuit is used for measuring the temperature of the contact of the isolating switch; the controller is used for determining a first resistance value change curve of the isolating switch according to the resistance value acquired in the measuring period; determining a second resistance value change curve of the isolating switch according to the contact temperature in the measuring period and the pre-stored corresponding relation of the temperature and the resistance value; and correcting the first resistance value change curve according to the second resistance value change curve, determining the corrected curve as the change curve of the contact resistor, and sending the change curve to the remote control terminal.
In one possible embodiment, the high frequency power supply circuit includes a high frequency power supply and a low frequency filter circuit, which are connected in series with each other and connected across the isolating switch.
In one possible implementation, the loop resistance measuring circuit includes a pre-amplifier circuit, an AD conversion circuit, and an arithmetic processing circuit.
In one possible embodiment, the controller is configured to determine a mean value of a first resistance value of the first resistance value variation curve and a second resistance value of the second resistance value variation curve at each time point in the measurement cycle as the resistance value of the contact resistor.
In a possible embodiment, the controller is further configured to determine a mean value of the variation curve of the contact resistance, and filter resistance value data of which the difference value from the mean value exceeds a preset threshold value.
In one possible implementation mode, the controller sequentially transmits each resistance value in the variation curve of the contact point resistance to the remote control end through the wireless communication circuit.
In a second aspect, an embodiment of the present application provides an online monitoring method for a disconnecting switch, including:
acquiring the resistance value and the contact temperature of the isolating switch;
determining a first resistance value change curve of the isolating switch according to the resistance value acquired in the measuring period;
determining a second resistance value change curve of the isolating switch according to the contact temperature in the measuring period and the pre-stored corresponding relation of the temperature and the resistance value;
and correcting the first resistance value change curve according to the second resistance value change curve, determining the corrected curve as the change curve of the contact resistor, and sending the change curve to the remote control terminal.
In one possible embodiment, the method further comprises: and filtering resistance value data of which the difference value with the mean value exceeds a preset threshold value according to the mean value of the change curve of the contact resistance.
In a third aspect, an embodiment of the present application provides a computer device, including: a processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, the processor and the memory communicate with each other through the bus when a computer device runs, and the machine-readable instructions, when executed by the processor, perform the steps of the method for monitoring the on-line monitoring of the disconnector as described in any one of the possible embodiments of the first aspect.
In a fourth aspect, the present application provides a computer-readable storage medium, where a computer program is stored, where the computer program is executed by a processor to perform the steps of the method for monitoring an online disconnector as described in any one of the possible implementation manners of the first aspect.
The beneficial effect of this application:
the application provides an isolator on-line measuring device, provide high frequency signal for isolator through high frequency power supply circuit, measure isolator's resistance through return circuit resistance measurement circuit, obtain first resistance change curve, and combine the corresponding relation of contact temperature and the temperature-resistance of prestoring in the measurement cycle, confirm isolator's second resistance change curve, revise first resistance change curve through second resistance change curve, with the change curve of finally obtaining contact resistance, and like this, can reduce the influence to the resistance measurement result because of external disturbance in the measurement process, make the measurement result accurately reflect contact resistance's change, thereby improve isolator fault monitoring's reliability.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the application and, together with the description, serve to explain the application and are not intended to limit the application.
Fig. 1 is a schematic structural diagram of an online monitoring device for a disconnecting switch according to an embodiment of the present disclosure;
fig. 2 is a second schematic structural diagram of an online monitoring device for a disconnecting switch according to an embodiment of the present disclosure;
fig. 3 is a schematic flowchart of an online monitoring method for a disconnector provided in the embodiment of the present application;
fig. 4 is a schematic diagram of a computer device provided in an embodiment of the present application.
Detailed Description
The present application will be further described with reference to the following drawings and examples.
It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.
At present, the contact quality of the isolating switch is usually judged by a method for measuring loop resistance, and in the actual measurement process, especially for monitoring the outdoor isolating switch, the measurement result is influenced by external environments such as rain, snow, electromagnetic interference and the like, so that the measurement result cannot directly reflect the change of contact resistance of the isolating switch, and the reliability of fault monitoring of the isolating switch is low. Based on the above, the application provides an on-line monitoring device and method for an isolating switch, which are used for improving the accuracy of the monitoring result of the isolating switch and enabling the monitoring result to accurately reflect the change of contact resistance of a contact.
Example one
Referring to fig. 1, fig. 1 is a schematic structural diagram of an online monitoring device for a disconnecting switch provided in an embodiment of the present application, and as shown in fig. 1, an online monitoring device for a disconnecting switch includes: the controller 110, the high-frequency power supply circuit 120, the loop resistance measuring circuit 130 and the temperature measuring circuit 140;
the high-frequency power circuit 120 is connected to two ends of the isolating switch 150, and provides a high-frequency signal for the isolating switch 150; the loop resistance measuring circuit 130 is used for measuring the resistance value of the isolating switch 150; the temperature measuring circuit 140 is used for measuring the temperature of the contact of the isolating switch 150; the controller 110 is configured to determine a first resistance value change curve of the isolating switch 150 according to the resistance value obtained in the measurement period; determining a second resistance value change curve of the isolating switch 150 according to the contact temperature in the measurement period and a pre-stored corresponding relation of the temperature and the resistance value; and correcting the first resistance value change curve according to the second resistance value change curve, determining the corrected curve as the change curve of the contact resistor, and sending the change curve to the remote control terminal.
In specific implementation, due to the fact that the contact resistance of the contact is increased, the temperature of the contact is increased, and under the environment of rain, snow, electromagnetic interference and the like, the measurement of the temperature of the contact is relatively stable, but the conversion process between the temperature of the contact and the resistance is relatively complex, and the temperature change is not obvious. Therefore, in the embodiment, the second resistance value change curve of the isolating switch is obtained through the temperature-resistance corresponding relation, and is used for correcting the resistance measurement value so as to improve the accuracy of the measurement result.
Specifically, a high-frequency power supply circuit transmits high-frequency waves to an isolating switch, and then a loop resistance measuring circuit obtains the resistance value of the isolating switch by measuring the voltage and the current of the high-frequency waves; the temperature of the contact of the isolating switch is measured by additionally arranging a temperature measuring circuit, and the measured resistance value and temperature data are sent to the controller. The controller determines a first resistance value change curve of the isolating switch according to the resistance value acquired in the measuring period, determines a second resistance value change curve of the isolating switch according to the measured contact temperature and the pre-stored temperature-resistance value corresponding relation, corrects the first resistance value change curve according to the second resistance value change curve, determines the corrected curve as the change curve of the contact resistance and sends the change curve to the remote control end.
As an alternative embodiment, as shown in fig. 2, the high frequency power circuit 120 includes a high frequency power source 121 and a low frequency filter circuit 122, and the high frequency power source 121 and the low frequency filter circuit 122 are connected in series with each other and connected to both ends of the isolation switch. In specific implementation, the high-frequency power supply transmits high-frequency waves to the isolating switch, and the low-frequency filter circuit blocks low-frequency current through high-frequency current to prevent power-frequency voltage from entering a measuring loop.
As an alternative embodiment, the loop resistance measuring circuit 130 includes a pre-amplifier circuit 131, an AD converter circuit 132, and an arithmetic processing circuit 133. In specific implementation, the resistance value of the signals at two ends of the isolating switch is obtained through the preamplifier circuit, the AD conversion circuit and the operation processing circuit, and the resistance value can be measured by adopting a voltage reduction method.
As an alternative embodiment, the controller 110 is configured to determine a mean value of a first resistance value of the first resistance value variation curve and a second resistance value of the second resistance value variation curve at each time point in the measurement cycle as the resistance value of the contact resistor. In a specific implementation, a mean value of the resistances at each time in the first resistance value change curve and the second resistance value change curve may be calculated, and the mean value may be determined as the resistance value of the contact resistor, or corresponding weights may be set, and the resistance value of the contact resistor may be calculated according to the corresponding weights.
As an optional embodiment, the controller 110 is further configured to determine a mean value of a variation curve of the contact resistance, and filter resistance value data of which a difference value from the mean value exceeds a preset threshold value. In specific implementation, in order to enable the measurement result to directly reflect the change of the contact resistance, after the change curve of the contact resistance is obtained, the abnormal resistance value can be filtered according to the mean value of the change curve.
As an alternative embodiment, the controller 110 sequentially transmits each resistance value in the variation curve of the contact resistance to the remote control terminal through the wireless communication circuit. In particular implementations, the wireless communications circuitry includes GPRS, wiFi, zigbee, and like wireless communications circuitry.
Example two
Referring to fig. 3, fig. 3 is a schematic flow chart of an online monitoring method for a disconnector according to an embodiment of the present disclosure. As shown in fig. 3, this embodiment further provides an online monitoring method for a disconnecting switch, including:
s301: acquiring the resistance value and the contact temperature of the isolating switch;
s302: determining a first resistance value change curve of the isolating switch according to the resistance value obtained in the measuring period;
s303: determining a second resistance value change curve of the isolating switch according to the contact temperature in the measuring period and the pre-stored corresponding relation of the temperature and the resistance value;
s304: and correcting the first resistance value change curve according to the second resistance value change curve, determining the corrected curve as the change curve of the contact resistor, and sending the change curve to the remote control terminal.
As an optional implementation, further comprising: and filtering resistance value data of which the difference value with the mean value exceeds a preset threshold value according to the mean value of the change curve of the contact resistance.
The method for monitoring the disconnecting switch on line in the embodiment is based on the same inventive concept as the device for monitoring the disconnecting switch on line, so the specific implementation manner of the method for monitoring the disconnecting switch on line can be found in the embodiment section of the device for monitoring the disconnecting switch on line in the foregoing, and is not described herein again.
EXAMPLE III
Referring to fig. 4, fig. 4 is a schematic diagram of a computer device according to an embodiment of the present application. As shown in fig. 4, the computer device 400 includes a processor 410, a memory 420, and a bus 430.
The memory 420 stores machine-readable instructions executable by the processor 410, when the computer device 400 runs, the processor 410 communicates with the memory 420 through the bus 430, and when the machine-readable instructions are executed by the processor 410, the steps of the online monitoring method for the disconnecting switch in the method embodiment shown in fig. 3 may be executed.
Example four
Based on the same application concept, embodiments of the present application further provide a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the steps of the online monitoring method for a disconnector described in the above method embodiments are executed.
It will be understood by those skilled in the art that all or part of the processes of the methods of the embodiments described above can be implemented by a computer program, which can be stored in a computer-readable storage medium, and when executed, can include the processes of the embodiments of the methods described above. The storage medium may be a magnetic disk, an optical disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), or the like.
The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims (10)
1. The utility model provides a isolator on-line monitoring device which characterized in that includes: the temperature measuring circuit comprises a controller, a high-frequency power supply circuit, a loop resistance measuring circuit and a temperature measuring circuit;
the high-frequency power supply circuit is connected to two ends of the isolating switch and provides a high-frequency signal for the isolating switch; the loop resistance measuring circuit is used for measuring the resistance value of the isolating switch; the temperature measuring circuit is used for measuring the temperature of the contact of the isolating switch; the controller is used for determining a first resistance value change curve of the isolating switch according to the resistance value acquired in the measuring period; determining a second resistance value change curve of the isolating switch according to the corresponding relation between the contact temperature in the measuring period and the pre-stored temperature-resistance value; and correcting the first resistance value change curve according to the second resistance value change curve, determining the corrected curve as the change curve of the contact resistor, and sending the change curve to the remote control terminal.
2. The on-line monitoring device for the disconnecting switch according to claim 1, wherein the high-frequency power supply circuit comprises a high-frequency power supply and a low-frequency filter circuit, and the high-frequency power supply and the low-frequency filter circuit are connected in series with each other and connected to two ends of the disconnecting switch.
3. The on-line monitoring device for the isolating switch according to claim 1, wherein the loop resistance measuring circuit comprises a pre-amplifying circuit, an AD converting circuit and an operation processing circuit.
4. The on-line monitoring device for the isolating switch as claimed in claim 1, wherein the controller is configured to determine a mean value of a first resistance value of the first resistance value variation curve and a second resistance value of the second resistance value variation curve at each time in the measurement period as the resistance value of the contact resistor.
5. The on-line monitoring device for the isolating switch as claimed in claim 1, wherein the controller is further configured to filter resistance value data, in which a difference value between a mean value of the variation curves of the contact resistance and the contact resistance exceeds a preset threshold value, according to the mean value.
6. The on-line monitoring device for the disconnecting switch according to claim 1, wherein the controller sequentially transmits each resistance value in the variation curve of the contact resistance to the remote control terminal through the wireless communication circuit.
7. An online monitoring method for a disconnecting switch is characterized by comprising the following steps:
acquiring the resistance value and the contact temperature of the isolating switch;
determining a first resistance value change curve of the isolating switch according to the resistance value acquired in the measuring period;
determining a second resistance value change curve of the isolating switch according to the contact temperature in the measuring period and the pre-stored corresponding relation of the temperature and the resistance value;
and correcting the first resistance value change curve according to the second resistance value change curve, determining the corrected curve as the change curve of the contact resistor, and sending the change curve to the remote control terminal.
8. The online monitoring method for the disconnecting switch according to claim 7, further comprising the following steps: and determining the mean value of the change curve of the contact resistance, and filtering resistance value data of which the difference value with the mean value exceeds a preset threshold value.
9. A computer device, comprising: a processor, a memory and a bus, wherein the memory stores machine readable instructions executable by the processor, the processor and the memory communicate through the bus when a computer device runs, and the machine readable instructions are executed by the processor to execute the steps of the isolating switch online monitoring method according to any one of claims 7 to 8.
10. A computer-readable storage medium, characterized in that the computer-readable storage medium has stored thereon a computer program which, when being executed by a processor, performs the steps of the method for on-line monitoring of a disconnector according to any one of claims 7-8.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210698682.2A CN115248375A (en) | 2022-06-20 | 2022-06-20 | Online monitoring device and method for isolating switch |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210698682.2A CN115248375A (en) | 2022-06-20 | 2022-06-20 | Online monitoring device and method for isolating switch |
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| CN115248375A true CN115248375A (en) | 2022-10-28 |
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| CN202210698682.2A Pending CN115248375A (en) | 2022-06-20 | 2022-06-20 | Online monitoring device and method for isolating switch |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117589841A (en) * | 2024-01-04 | 2024-02-23 | 中国第一汽车股份有限公司 | Wide-range oxygen sensor, testing circuit and testing method |
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2022
- 2022-06-20 CN CN202210698682.2A patent/CN115248375A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117589841A (en) * | 2024-01-04 | 2024-02-23 | 中国第一汽车股份有限公司 | Wide-range oxygen sensor, testing circuit and testing method |
| CN117589841B (en) * | 2024-01-04 | 2024-05-14 | 中国第一汽车股份有限公司 | Wide-range oxygen sensor, testing circuit and testing method |
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