CN114878959A - GPS time synchronization precision detection method for cable fault online distance measurement - Google Patents

GPS time synchronization precision detection method for cable fault online distance measurement Download PDF

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Publication number
CN114878959A
CN114878959A CN202210398079.2A CN202210398079A CN114878959A CN 114878959 A CN114878959 A CN 114878959A CN 202210398079 A CN202210398079 A CN 202210398079A CN 114878959 A CN114878959 A CN 114878959A
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China
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pulse
cable fault
signal
traveling wave
gps time
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CN202210398079.2A
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Chinese (zh)
Inventor
许强
袁奇
叶頲
何邦乐
王骁迪
原佳亮
朱亦嘉
楼铁城
吴辰斌
顾黄晶
谢素娟
魏康妮
张伟
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State Grid Shanghai Electric Power Co Ltd
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State Grid Shanghai Electric Power Co Ltd
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Priority to CN202210398079.2A priority Critical patent/CN114878959A/en
Publication of CN114878959A publication Critical patent/CN114878959A/en
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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
    • G01R31/08—Locating faults in cables, transmission lines, or networks
    • G01R31/081—Locating faults in cables, transmission lines, or networks according to type of conductors
    • G01R31/083—Locating faults in cables, transmission lines, or networks according to type of conductors in cables, e.g. underground
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • 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

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Locating Faults (AREA)

Abstract

The invention relates to a GPS time synchronization precision detection method for cable fault online distance measurement, which comprises the following steps: collecting a cable fault traveling wave signal, and extracting a traveling wave head characteristic signal from the cable fault traveling wave signal; simulating a traveling wave head characteristic signal through a pulse generator to generate pulse signals, and respectively transmitting the pulse signals to a plurality of cable fault on-line distance measuring devices, wherein each cable fault on-line distance measuring device completes GPS time synchronization; and acquiring the pulse signal trigger time recorded by each cable fault on-line distance measuring device, and taking the difference between every two pulse signal trigger times as a GPS time setting error. Compared with the prior art, the invention provides the detection method which is simple to operate and convenient to realize for the GPS time synchronization error of the cable fault online distance measurement.

Description

GPS time synchronization precision detection method for cable fault online distance measurement
Technical Field
The invention relates to the technical field of power cables, in particular to a GPS time synchronization precision detection method for cable fault online distance measurement.
Background
With the development of the GPS technology, the precise time synchronization double-end traveling wave method based on the GPS is realized. The double-end traveling wave method calculates the fault position by calculating the time difference of the fault traveling wave reaching the two ends of the line, and the ranging precision is not influenced by the line length, the fault position, the fault type, the grounding resistance and other factors. For cable fault on-line location, the key is that the location device can accurately record the time of the fault traveling wave reaching the two ends of the line. The traditional transmission line traveling wave distance measurement has low requirement on errors, generally requires within 500 meters, corresponds to a GPS time synchronization error of 1 microsecond, and the cable fault on-line distance measurement requires the GPS time synchronization error to be within dozens of nanoseconds so as to ensure that the fault positioning error is within ten meters.
At present, a GPS time synchronization system applied to power equipment is mainly implemented by the following methods: hard time synchronization, soft time synchronization and coding time synchronization. The GPS time synchronization scheme is increasingly perfected, and the time synchronization accuracy is greatly improved by combining hard and soft time synchronization and improving code time synchronization, but the methods for verifying the GPS time synchronization accuracy are very few. Therefore, a method for checking the GPS time synchronization accuracy of a plurality of cable fault online distance measuring devices is urgently needed so as to verify the positioning accuracy of cable fault online distance measurement.
Disclosure of Invention
The invention aims to overcome the defect of insufficient verification of the on-line distance measurement and positioning accuracy of the cable fault in the prior art, and provides a GPS time synchronization accuracy detection method for the on-line distance measurement of the cable fault, which is simple in operation and convenient to implement, according to the trigger principle of the on-line distance measurement of the cable fault.
The purpose of the invention can be realized by the following technical scheme:
a GPS time synchronization precision detection method for cable fault online distance measurement comprises the following steps:
collecting a cable fault traveling wave signal, and extracting a traveling wave head characteristic signal from the cable fault traveling wave signal;
simulating the traveling wave head characteristic signal by a pulse generator to generate pulse signals, and respectively transmitting the pulse signals to a plurality of cable fault on-line distance measuring devices, wherein each cable fault on-line distance measuring device completes GPS time synchronization;
and acquiring the pulse signal trigger time recorded by each cable fault on-line distance measuring device, and taking the difference between every two pulse signal trigger times as a GPS time setting error.
Further, the lengths of the signal output lines of the pulse generator connected between the cable fault on-line distance measuring devices are equal.
Further, the pulse generator comprises a pulse generating unit, a display unit, an operating unit and a first control unit, wherein the first control unit is respectively connected with the pulse generating unit, the display unit and the operating unit, and the pulse generating unit is used for generating pulse signals with different pulse widths, amplitudes and rise times; the operation unit is used for setting pulse parameters; the display unit is used for displaying the currently set pulse parameters; the first control unit is used for receiving the pulse parameter signal, transmitting the pulse parameter signal to the display unit, calculating a pulse instruction according to the pulse parameter signal, and sending the pulse instruction to the pulse generation unit.
Further, different traveling wave head characteristic signals in the cable fault signal are simulated by setting different pulse widths, amplitudes and rise times.
Furthermore, the cable fault on-line distance measuring device comprises a GPS time comparing unit, a triggering unit, a second control unit and a background data unit, wherein the second control unit is respectively connected with the GPS time comparing unit, the triggering unit and the background data unit, and the GPS time comparing unit is used for receiving GPS satellite signals so as to acquire time information and send the time information to the second control unit; the trigger unit is used for receiving the pulse signal, generating a trigger signal and pulse data and sending the trigger signal and the pulse data to the second control unit; the second control unit is used for recording trigger time according to the received trigger signal and sending the trigger time and the received pulse data to the background data unit; and the background data unit is used for storing the trigger time and the pulse data transmitted by the second control unit.
Further, the average value of the GPS time setting errors is obtained by carrying out a plurality of tests under the same pulse signal, and the average value is used as a final GPS time setting error checking result.
And further, the traveling wave waveform data stored in the cable fault on-line distance measuring device is directly called as the cable fault traveling wave signal.
And further, acquiring a cable fault traveling wave signal from the cable through the oscilloscope and the traveling wave signal sensor.
Further, the traveling wave signal sensor comprises a voltage traveling wave sensor or a current traveling wave sensor.
Further, after the cable fault traveling wave signals are obtained, the rising time, the amplitude and the pulse width of the traveling wave head are measured, and the traveling wave head characteristic signals of a plurality of groups of cable faults are obtained.
Compared with the prior art, the invention has the following advantages:
(1) aiming at the GPS time synchronization error of the cable fault on-line distance measurement, a detection method which is simple in operation and convenient to realize is provided, and the GPS time synchronization error is obtained by respectively comparing the signal trigger time through simulating the traveling wave head characteristic signal of the fault signal and respectively transmitting the traveling wave head characteristic signal to each cable fault on-line distance measurement device which is synchronized by time.
(2) The method can simultaneously test more than two cable fault on-line distance measuring devices, the triggering time of the devices is pairwise differenced to obtain the time difference, and the efficiency of testing the GPS time synchronization precision is improved.
(3) The method provides that the pulse generator can simulate the traveling wave heads of various cable faults, and the triggering effectiveness of the device under different fault conditions on the site is tested and verified for many times.
Drawings
FIG. 1 is a system block diagram of a GPS time synchronization accuracy detection method for cable fault online distance measurement provided in an embodiment of the present invention;
fig. 2 is a system block diagram of an online cable fault distance measuring device provided in an embodiment of the present invention;
fig. 3 is a system block diagram of a pulse generator provided in 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 clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be obtained by a person skilled in the art without inventive step based on the embodiments of the present invention, are within the scope of protection of the present invention.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or the orientations or positional relationships that the products of the present invention are conventionally placed in use, and are only used for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.
It should be noted that the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.
Furthermore, the terms "horizontal", "vertical" and the like do not imply that the components are required to be absolutely horizontal or pendant, but rather may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.
Example 1
As shown in fig. 1, the present embodiment provides a method for checking accuracy of GPS time synchronization for online distance measurement of cable faults, including the following steps:
collecting a cable fault traveling wave signal, and extracting a traveling wave head characteristic signal from the cable fault traveling wave signal;
simulating a traveling wave head characteristic signal through a pulse generator to generate pulse signals, and respectively transmitting the pulse signals to a plurality of cable fault on-line distance measuring devices, wherein each cable fault on-line distance measuring device completes GPS time synchronization;
and acquiring the pulse signal trigger time recorded by each cable fault on-line distance measuring device, and taking the difference between every two pulse signal trigger times as a GPS time setting error.
The lengths of signal output lines of the pulse generator connected among the cable fault on-line distance measuring devices are equal.
In the scheme, firstly, the characteristics of a traveling wave head collected when a cable fault occurs are extracted, a pulse generator is used for simulating the wave head signal, then the signal is used for triggering a plurality of cable fault online distance measuring devices synchronously completed by a GPS, finally, the recorded triggering time is checked in a background of the online distance measuring devices, and the difference between the triggering times of the devices is the GPS time setting error.
Structurally, the scheme comprises the pulse generator and the cable fault on-line distance measuring device, and the pulse generator is used for triggering the cable fault on-line distance measuring device. The pulse generator comprises a pulse generating unit, a display unit, an operation unit and a control unit; the cable fault on-line distance measuring device comprises a GPS time setting unit, a triggering unit, a control unit and a background data unit. When the inspection method is used, the number of the cable fault online distance measuring devices is at least 2.
Specifically, as shown in the figure, the pulse generator comprises a pulse generating unit, a display unit, an operating unit and a first control unit, wherein the first control unit is respectively connected with the pulse generating unit, the display unit and the operating unit, and the pulse generating unit is used for generating pulse signals with different pulse widths, amplitudes and rise times; the operation unit is used for setting pulse parameters; the display unit is used for displaying the currently set pulse parameters; the first control unit is used for receiving the pulse parameter signal, transmitting the pulse parameter signal to the display unit, calculating a pulse instruction according to the pulse parameter signal, and sending the pulse instruction to the pulse generation unit.
Different traveling wave head characteristic signals in the cable fault signal are simulated by setting different pulse widths, amplitudes and rise times in the pulse generator.
As shown in fig. 2, the cable fault on-line distance measuring device includes a GPS time comparing unit, a triggering unit, a second control unit and a background data unit, the second control unit is respectively connected to the GPS time comparing unit, the triggering unit and the background data unit, the GPS time comparing unit is used for receiving GPS satellite signals, so as to obtain time information and send the time information to the second control unit; the trigger unit is used for receiving the pulse signal, thereby generating a trigger signal and pulse data and sending the trigger signal and the pulse data to the second control unit; the second control unit is used for recording the trigger time according to the received trigger signal and sending the trigger time and the received pulse data to the background data unit; the background data unit is used for storing the trigger time and the pulse data transmitted by the second control unit. The average value of the GPS time synchronization errors is obtained by testing for multiple times under the same pulse signal and is used as the final GPS time synchronization error checking result
The method for extracting the wave head characteristics of the cable fault traveling wave comprises two implementation modes: firstly, the traveling wave waveform data stored in the cable fault on-line distance measuring device is directly called to be used as a cable fault traveling wave signal; and secondly, acquiring a cable fault traveling wave signal from the cable through an oscilloscope and a traveling wave signal sensor, wherein the traveling wave signal sensor comprises a voltage traveling wave sensor or a current traveling wave sensor.
When the device is used, after the rising time, the amplitude and the pulse width characteristic of the cable fault traveling wave head are extracted, the rising time, the amplitude and the pulse width of the pulse generator are set according to the extracted traveling wave head characteristic. And connecting a pulse generator and the trigger ports of the plurality of cable fault on-line distance measuring devices by using a signal output line, outputting pulse signals of the pulse generator, checking background trigger time of the cable fault on-line distance measuring devices, and calculating a trigger time difference between the two devices. The cable fault traveling wave characteristics are related to the length, the fault position and the fault property of the cable, and a pulse generator can be used for simulating a plurality of fault traveling wave heads (different rise times, amplitudes and pulse widths); in order to reduce GPS time synchronization precision errors caused by triggering, the lengths of signal output lines from a pulse generator to two or more cable fault online devices are equal; according to the principle of the detection method, the method is used as a detection method for the GPS time synchronization precision of more than two cable fault online distance measuring devices, and in order to obtain more accurate time difference results, multiple tests are required to be carried out under the same trigger condition to obtain an average value.
The specific implementation process of the scheme in this embodiment includes the following steps:
s1: and extracting the wave head characteristics of the cable fault traveling wave. The method comprises the following steps of firstly, directly calling traveling wave waveform data in a background data unit of the cable fault on-line distance measuring device; and secondly, acquiring the cable fault traveling wave by using a voltage/current traveling wave sensor equipped with an oscilloscope and a cable fault online distance measuring device. After a plurality of cable fault traveling wave waveforms are obtained, the rise time, the amplitude and the pulse width of the traveling wave head are analyzed and measured, and a plurality of groups of cable fault traveling wave head characteristics are obtained.
S2: and waiting for the GPS synchronization of the devices. And electrifying the cable fault on-line distance measuring devices, observing the indication state of the GPS time synchronization unit, and waiting for completing the synchronization of the GPS clock.
S3: and simulating the wave head characteristics of the traveling wave of the cable fault. And (3) setting corresponding pulse rise time, amplitude and pulse width in an operation unit of the pulse generator according to the wave head characteristics of the cable fault traveling wave extracted in the step (1).
S4: and simultaneously triggering a plurality of cable fault on-line distance measuring devices by using a pulse generator. And connecting the pulse generator to the trigger ports of the multiple cable fault online distance measuring devices by using signal output lines with equal length, and outputting pulse signals by the pulse generating unit.
S5: and taking the device record and counting. After each cable fault on-line distance measuring device is triggered, the triggering time is automatically recorded and stored according to the GPS clock, the data of the background data unit of each device are read, the triggering time of all the devices is counted, the time difference between the two devices is calculated, and the average value is obtained through multiple tests under the same condition.
The foregoing detailed description of the preferred embodiments of the invention has been presented. It should be understood that numerous modifications and variations could be devised by those skilled in the art in light of the present teachings without departing from the inventive concepts. Therefore, the technical solutions available to those skilled in the art through logic analysis, reasoning and limited experiments based on the prior art according to the concept of the present invention should be within the scope of protection defined by the claims.

Claims (10)

1. A GPS time synchronization precision detection method for cable fault online distance measurement is characterized by comprising the following steps:
collecting a cable fault traveling wave signal, and extracting a traveling wave head characteristic signal from the cable fault traveling wave signal;
simulating the traveling wave head characteristic signal by a pulse generator to generate pulse signals, and respectively transmitting the pulse signals to a plurality of cable fault on-line distance measuring devices, wherein each cable fault on-line distance measuring device completes GPS time synchronization;
and acquiring the pulse signal trigger time recorded by each cable fault on-line distance measuring device, and taking the difference between every two pulse signal trigger times as a GPS time setting error.
2. The method for checking the accuracy of the GPS time synchronization for the online distance measurement of the cable faults as claimed in claim 1, wherein the lengths of the signal output lines of the pulse generator connecting the cable fault online distance measurement devices are equal.
3. The GPS time tick accuracy test method for cable fault online distance measurement according to claim 1, wherein the pulse generator comprises a pulse generation unit, a display unit, an operation unit and a first control unit, the first control unit is respectively connected with the pulse generation unit, the display unit and the operation unit, and the pulse generation unit is used for generating pulse signals with different pulse widths, amplitudes and rise times; the operation unit is used for setting pulse parameters; the display unit is used for displaying the currently set pulse parameters; the first control unit is used for receiving the pulse parameter signal, transmitting the pulse parameter signal to the display unit, calculating a pulse instruction according to the pulse parameter signal, and sending the pulse instruction to the pulse generation unit.
4. The GPS time synchronization accuracy detection method for the cable fault online distance measurement as claimed in claim 3, wherein different travelling wave head characteristic signals in the cable fault signal are simulated by setting different pulse widths, amplitudes and rise times.
5. The GPS time tick precision test method for the cable fault online distance measurement according to claim 1, wherein the cable fault online distance measurement device comprises a GPS time tick unit, a trigger unit, a second control unit and a background data unit, the second control unit is respectively connected with the GPS time tick unit, the trigger unit and the background data unit, the GPS time tick unit is used for receiving GPS satellite signals, thereby acquiring time information and sending the time information to the second control unit; the trigger unit is used for receiving the pulse signal, generating a trigger signal and pulse data and sending the trigger signal and the pulse data to the second control unit; the second control unit is used for recording trigger time according to the received trigger signal and sending the trigger time and the received pulse data to the background data unit; and the background data unit is used for storing the trigger time and the pulse data transmitted by the second control unit.
6. The method for checking the accuracy of the GPS time synchronization used for the online distance measurement of the cable fault as claimed in claim 1, wherein the average value of the GPS time synchronization errors is obtained by performing a plurality of tests under the same pulse signal as the final GPS time synchronization error checking result.
7. The GPS time synchronization accuracy inspection method for the cable fault online distance measurement as claimed in claim 1, characterized in that the traveling wave waveform data stored in the cable fault online distance measurement device is directly called as the cable fault traveling wave signal.
8. The method for testing the accuracy of the GPS time synchronization for the online distance measurement of the cable fault as claimed in claim 1, wherein the cable fault traveling wave signal is collected from the cable by an oscilloscope and a traveling wave signal sensor.
9. The method for checking the accuracy of the GPS time synchronization for the cable fault online distance measurement as claimed in claim 8, wherein the traveling wave signal sensor comprises a voltage traveling wave sensor or a current traveling wave sensor.
10. The GPS time synchronization precision detection method for cable fault online distance measurement according to claim 1, wherein after the cable fault traveling wave signal is obtained, a plurality of groups of traveling wave head characteristic signals of the cable fault are obtained by measuring the rise time, the amplitude and the pulse width of the traveling wave head.
CN202210398079.2A 2022-04-12 2022-04-12 GPS time synchronization precision detection method for cable fault online distance measurement Pending CN114878959A (en)

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CN202210398079.2A CN114878959A (en) 2022-04-12 2022-04-12 GPS time synchronization precision detection method for cable fault online distance measurement

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210398079.2A CN114878959A (en) 2022-04-12 2022-04-12 GPS time synchronization precision detection method for cable fault online distance measurement

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