CN115825649A - Cable fault point midpoint traveling wave distance measurement online positioning system based on current magnetic signal and parameter optimization variational modal decomposition - Google Patents
Cable fault point midpoint traveling wave distance measurement online positioning system based on current magnetic signal and parameter optimization variational modal decomposition Download PDFInfo
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- CN115825649A CN115825649A CN202211478552.4A CN202211478552A CN115825649A CN 115825649 A CN115825649 A CN 115825649A CN 202211478552 A CN202211478552 A CN 202211478552A CN 115825649 A CN115825649 A CN 115825649A
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- 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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Abstract
The invention discloses a cable fault point midpoint traveling wave distance measurement online positioning system based on current magneto-induced signals and parameter optimization variational modal decomposition. The main components comprise a power cable to be detected, a current magnetic signal extraction sensor, an analog signal program control amplifier, an A/D converter, a micro processor, a 4G communication module, a Web client server, a numerical calculation server and a client display terminal. The invention relates to the technical field of power cable fault location. The invention has the advantages that power failure is not needed, normal production is not influenced, the non-contact current magnetic signal extraction sensor is used for measuring current data in the cable at the head end, the middle point and the tail end of the three-phase cable (the head end and the tail end are mainly used for calculating middle point data, and the head end and the tail end are used for carrying out auxiliary measurement when the noise is overlarge or other factors are interfered), the traveling wave head is calibrated by using the variation mode decomposition of parameter optimization in the numerical calculation server, the position information of a fault point is obtained after calculation by using the proposed middle point traveling wave method, and the man-machine interaction can be carried out.
Description
Technical Field
The invention relates to the field of power cable fault location, in particular to a cable fault point midpoint traveling wave location on-line positioning system based on current magnetic signals and parameter optimization variational modal decomposition.
Background
As the service life of the power network increases, the probability of failure occurrence increases, and it is necessary to locate the failure in time, which not only can accelerate the maintenance time, but also can accelerate the processing speed of the subsequent operation. Aiming at the problems of incomplete detection, power failure detection and the like existing in the conventional diagnosis method in the field of power cable fault location, the system for locating the midpoint traveling wave location of the cable fault point on line based on the current magneto-induced signal and parameter optimization variational modal decomposition is provided. The method comprises the steps of extracting a current signal of a power cable by using a midpoint traveling wave ranging method and a non-contact type current magneto-induced signal extraction sensor, carrying out phase-mode conversion, obtaining a traveling wave component, obtaining wave head data by applying parameter optimization variation mode decomposition, further calculating a fault position, and transmitting information to a user.
The traditional distance measurement method for the power cable is as follows:
a single-ended distance measurement method: and the single-end distance measurement method only extracts the fault electrical quantity at one end of the line, calibrates the time when the initial fault traveling wave reaches the measuring end and the time when the reflected wave reaches the measuring end, and substitutes the time into a single-end distance measurement formula to determine the fault position.
Double-end distance measurement: and extracting fault electrical quantities at the head end and the tail end of the line by a double-end distance measurement method, calibrating the time when the initial fault traveling wave reaches the head end and the tail end, and substituting the time into a double-end distance measurement formula to determine the fault position.
The two methods have the problem that the traveling wave speed needs to be acquired in advance for calculation, but the line parameters are greatly influenced by the environment, and the traveling wave speed is also influenced accordingly.
The traditional calibration method of the traveling wave head is wavelet transformation and Hilbert-Huang transformation, and the distance measurement error of the currently adopted methods such as wavelet transformation, empirical mode decomposition and the like is large, and even the risk of failure is possible. In order to solve the problems, the distance measurement method is used in actual measurement, and the cable fault point midpoint traveling wave distance measurement online positioning system based on current magnetic signals and parameter optimization variational modal decomposition is provided.
Disclosure of Invention
Technical problem to be solved
Aiming at the defects of the prior art, the invention provides a cable fault point midpoint traveling wave ranging on-line positioning system based on current magneto-induced signals and parameter optimization variational modal decomposition, and solves the problems of overlarge measurement error caused by inaccurate wave speed and overlarge calculation error caused by inaccurate traveling wave head calibration in the conventional ranging method in the field of power cable ranging.
(II) technical scheme
In order to achieve the purpose, the invention is realized by the following technical scheme: a cable fault point midpoint traveling wave distance measurement online positioning system based on current magneto-induced signals and parameter optimization variational modal decomposition comprises a sensing layer, a transmission layer, a platform layer and an application layer, and the structure comprises a current magneto-induced signal sending end, a current magneto-induced signal receiving end and a human-computer interaction end. The main components comprise a power cable to be detected, a current magnetic signal extraction sensor, an analog signal program control amplifier, an A/D converter, a micro processor, a 4G communication module, a Web client server, a numerical calculation server and a client display terminal.
The output end of a current magnetic signal extraction sensor in the current magnetic signal sending end is electrically connected with the input end of an analog signal program-controlled amplifier through a lead, the output end of the analog signal program-controlled amplifier is electrically connected with the output end of an A/D converter through a lead, the output end of the A/D converter is electrically connected with the input end of a microprocessor through a lead, the microprocessor realizes the transmission of current magnetic signals with a current magnetic signal receiving layer through a 4G communication module, the current magnetic signals enter a numerical calculation server for fault distance calculation after being preprocessed through a denoising program, the numerical calculation server realizes the transmission of fault position information with a human-computer interaction layer through a 4G communication module, and a Web client server in the human-computer interaction layer is connected with a network client display terminal.
Preferably, the current magnetic signal extraction sensor is respectively connected with three phases of electricity of the power cable, and the three signals respectively come from the three phases of electricity A, B and C of the power cable.
Preferably, the signal collected by the current magnetic signal sensor is sent to an analog signal program control amplifier, and the output signal of the analog signal program control amplifier is sent to an A/D converter.
Preferably, the digital signal output by the a/D converter is sent to a microprocessor, and the data preprocessed by the microprocessor through operation is wirelessly transmitted to a current magneto-induced signal receiving end through a 4G communication module.
Preferably, the preprocessed current magnetic signal data are sent to a numerical calculation server for fault distance calculation after passing through a denoising program.
Preferably, the fault location information output by the numerical calculation server is wirelessly transmitted to a Web client server of the human-computer interaction terminal through the 4G communication module.
Preferably, a client can obtain the cable fault position information and the processing suggestion only by accessing the Web client server through the client display terminal, so that maintenance operation is performed.
Preferably, the current magnetic signal extraction sensor is used for extracting current magnetic signals of three phases A, B and C of the power cable, and the sensing layer is used for collecting, analyzing and processing the current magnetic signals.
Preferably, the transmission layer is used for transmitting the signal data to the Web server, the Web server sorts the data and then sends the data to the cable fault distance numerical calculation server, and the platform layer is used for calculating and analyzing the data from the Web server by a cable fault point midpoint traveling wave distance measurement algorithm of parameter optimization variational modal decomposition, and sending the result back to the Web server.
Preferably, the application layer is configured to display the diagnosis result on the user terminal through the Web server.
Preferably, three-phase current and voltage signals at two ends are coupled with each other, and a newly proposed phase-mode transformation matrix is adopted for decoupling, wherein the phase-mode transformation matrix is as follows:
the phase-mode transformation calculation formula is as follows:
wherein u is a ,u b ,u c ,i a ,i b ,i c Fault voltage and current travelling wave u on A, B and C phase lines 0 ,u α ,u β ,i 0 ,i α ,i β Respectively are the 0 mode, alpha mode and beta mode components of the voltage and current traveling wave.
Preferably, the power cable fault location is classified:
a fault occurs ON the MO and a fault occurs ON the ON;
wherein, MO is the power cable left side, and ON is the power cable right side.
Preferably, the velocity is calculated by the formula
The fault distance is calculated by the formula
Wherein t is 1 The moment at which the travelling wave passes the midpoint for the first time, t 2 The moment t when the first traveling wave passes through the midpoint after being reflected by the bus M 3 The moment when the first traveling wave passes through the midpoint after being reflected by the bus N.
Preferably, the cable fault distance numerical calculation server decomposes the traveling wave characteristics by using variational modal decomposition optimized by an Ulva-gull optimization algorithm, performs wave head calibration by using a Teager-Kaiser energy operator, and performs fault positioning by using the obtained time data.
(III) advantageous effects
The utility model provides a mid point travelling wave range finding on-line positioning system of cable fault point based on electric current magnetic signal and parameter optimization variational modal decomposition. Compared with the prior art, the method has the following beneficial effects: the sensor comprises a sensing layer, a transmission layer, a platform layer and an application layer, wherein the sensor structure comprises a current magnetic signal sending end, a current magnetic signal receiving end and a human-computer interaction end. The main components comprise a power cable to be detected, a current magnetic signal extraction sensor, an analog signal program control amplifier, an A/D converter, a micro processor, a 4G communication module, a Web client server, a numerical calculation server and a client display terminal. By using the invention, power-off is not needed, the influence of wave speed on traveling wave distance measurement is eliminated, and the wave head calibration is more accurate. The non-contact current magnetic signal extraction sensor is used for measuring current data in a cable at the head end, the middle point and the tail end of a three-phase cable (the main calculation of the middle point data is performed, and the head end and the tail end perform auxiliary measurement in order to prevent overlarge noise or other factors from interfering), and obtaining the position information of a fault point after calculation.
Drawings
FIG. 1 is a schematic block diagram of the system architecture of the present invention
FIG. 2 is a schematic block diagram illustrating the structure of the sensing layer, the transport layer, the platform layer and the application layer of the present invention in FIG. 2
FIG. 3 and FIG. 4 are schematic diagrams of the midpoint traveling wave method
FIG. 5 is a flowchart of a variational modal decomposition algorithm optimized by the Woofer optimization algorithm
Detailed Description
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 only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1-5, an embodiment of the present invention provides a technical solution: an on-line location system for mid-point traveling wave distance measurement of cable fault points based on current magnetic signals and parameter optimization variation modal decomposition,
the sensor comprises a sensing layer, a transmission layer, a platform layer and an application layer, wherein the sensor structure comprises a current magnetic signal sending end, a current magnetic signal receiving end and a human-computer interaction end. The main components comprise a power cable to be detected, a current magnetic signal extraction sensor, an analog signal program control amplifier, an A/D converter, a micro processor, a 4G communication module, a Web client server, a numerical calculation server and a client display terminal.
In the embodiment of the invention, the output ends of current magnetic signal extraction sensors in a current magnetic signal sending end are electrically connected with the input end of an analog signal program control amplifier through a lead, the output end of the analog signal program control amplifier is electrically connected with the output end of an A/D converter through a lead, the output end of the A/D converter is electrically connected with the input end of a microprocessor through a lead, the microprocessor realizes the transmission of current magnetic signals with a current magnetic signal receiving layer through a 4G communication module, the current magnetic signals enter a numerical calculation server for fault distance calculation after being preprocessed through a denoising program, the numerical calculation server realizes the transmission of fault position information with a human-computer interaction layer through a 4G communication module, and a Web client server in the human-computer interaction layer is connected with a network client display terminal.
In the embodiment of the invention, the signal collected by the current magnetic signal sensor is sent to the analog signal program control amplifier, and the output signal of the analog signal program control amplifier is sent to the A/D converter. And the digital signal output by the A/D converter is sent to a microprocessor, and the data preprocessed by the microprocessor operation is wirelessly transmitted to a current magneto-induced signal receiving end through a 4G communication module. And sending the preprocessed current magnetic signal data into a numerical calculation server for fault distance calculation after passing through a denoising program. And the fault position information output by the numerical calculation server is wirelessly transmitted to a Web client server of a man-machine interaction end through a 4G communication module. And the client can obtain the cable fault position information and the processing suggestion only by accessing the Web client server through the client display terminal, so that the maintenance operation is carried out.
In the embodiment of the invention, the current magnetic signal extraction sensor is used for extracting current magnetic signals of three-phase power A, B and C of the power cable, and the sensing layer is used for collecting, analyzing and processing the current magnetic signals. The transmission layer is used for transmitting signal data to the Web server, the Web server sorts the data and then transmits the data to the cable fault distance numerical calculation server, and the platform layer is used for calculating and analyzing the data from the Web server by a cable fault point midpoint traveling wave distance measurement algorithm of parameter optimization variational modal decomposition, and transmitting the result back to the Web server. And the application layer is used for displaying the diagnosis result on the user terminal through the Web server.
In the embodiment of the invention, three-phase current and voltage signals at two ends are coupled with each other, and decoupling is carried out by adopting a newly proposed phase-mode transformation matrix, wherein the phase-mode transformation matrix is as follows:
the phase-mode transformation calculation formula is as follows:
wherein u is a ,u b ,u c ,i a ,i b ,i c Fault voltage and current travelling wave u on A, B and C phase lines 0 ,u α ,u β ,i 0 ,i α ,i β Respectively are the 0 mode, alpha mode and beta mode components of the voltage and current traveling wave.
In the embodiment of the invention, the fault positions of the power cables are classified: a fault occurs ON the MO and a fault occurs ON the ON;
wherein, MO is the power cable left side, and ON is the power cable right side.
The velocity is calculated by the formula
The fault distance is calculated by the formula
Wherein t is 1 The moment at which the travelling wave passes the midpoint for the first time, t 2 The time when the first traveling wave passes through the midpoint after being reflected by the bus M, t 3 The moment when the first traveling wave passes through the midpoint after being reflected by the bus N.
In the embodiment of the invention, the cable fault distance numerical calculation server decomposes the traveling wave characteristics by using variational modal decomposition optimized by an Ulva optimization algorithm, performs wave head calibration by using a Teager-Kaiser energy operator, and performs fault positioning by using the obtained time data.
In conclusion, the invention does not need power failure, monitors on line, does not influence normal production, eliminates the influence of wave speed on traveling wave distance measurement, and has more accurate wave head calibration. According to the method, traveling wave head data are obtained after extraction and operation of power cable current signals, the problem of distance measurement errors caused by inaccurate wave speed in the traditional traveling wave distance measurement method is solved by using a midpoint traveling wave method, and the wave head calibration is more accurate by using parameter optimization variational modal decomposition.
And those not described in detail in this specification are well within the skill of those in the art. It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (11)
1. The utility model provides a cable fault point mid point travelling wave range finding on-line positioning system based on electric current magnetic signal and parameter optimization variational modal decomposition which characterized in that: the sensor comprises a sensing layer, a transmission layer, a platform layer and an application layer, wherein the sensor structure comprises a current magnetic signal sending end, a current magnetic signal receiving end and a human-computer interaction end. The main components comprise a power cable to be detected, a current magnetic signal extraction sensor, an analog signal program control amplifier, an A/D converter, a micro processor, a 4G communication module, a Web client server, a numerical calculation server and a client display terminal;
the output end of a current magnetic signal extraction sensor in the current magnetic signal sending end is electrically connected with the input end of an analog signal program-controlled amplifier through a lead, the output end of the analog signal program-controlled amplifier is electrically connected with the output end of an A/D converter through a lead, the output end of the A/D converter is electrically connected with the input end of a microprocessor through a lead, the microprocessor realizes the transmission of current magnetic signals with a current magnetic signal receiving layer through a 4G communication module, the current magnetic signals enter a numerical calculation server for fault distance calculation after being preprocessed through a denoising program, the numerical calculation server realizes the transmission of fault position information with a human-computer interaction layer through a 4G communication module, and a Web client server in the human-computer interaction layer is connected with a network client display terminal.
2. The cable fault point midpoint traveling wave ranging on-line positioning system based on current magnetic signals and parameter optimization variational modal decomposition as claimed in claim 1, wherein: the current magnetic signal extraction sensor is respectively connected with three phases of electricity of the power cable, and the three signals respectively come from three phases of electricity A, B and C of the power cable.
3. The cable fault point midpoint traveling wave ranging on-line positioning system based on current magnetic signals and parameter optimization variational modal decomposition as claimed in claim 2, wherein: and sending the signal acquired by the current magnetic signal sensor to an analog signal program control amplifier, and sending the output signal of the analog signal program control amplifier to an A/D converter.
4. The cable fault point midpoint traveling wave ranging on-line positioning system based on current magnetic signals and parameter optimization variational modal decomposition as claimed in claim 3, wherein: and the digital signal output by the A/D converter is sent to a microprocessor, and the data preprocessed by the microprocessor operation is wirelessly transmitted to a current magneto-induced signal receiving end through a 4G communication module. And sending the preprocessed current magnetic signal data into a numerical calculation server for fault distance calculation after passing through a denoising program. And the fault position information output by the numerical calculation server is wirelessly transmitted to a Web client server of a man-machine interaction end through a 4G communication module.
5. The cable fault point midpoint traveling wave ranging on-line positioning system based on the current magnetic signal and the parameter optimization variational modal decomposition as claimed in claim 4, wherein: and the client can obtain the cable fault position information and the processing suggestion only by accessing the Web client server through the client display terminal, so that the maintenance operation is carried out.
6. The cable fault point midpoint traveling wave ranging on-line positioning system based on current magnetic signals and parameter optimization variational modal decomposition as claimed in claim 1, wherein: the current magnetic signal extraction sensor is used for extracting current magnetic signals of three-phase power A, B and C of the power cable, and the sensing layer is used for collecting, analyzing and processing the current magnetic signals.
7. The cable fault point midpoint traveling wave ranging on-line positioning system based on current magnetic signals and parameter optimization variational modal decomposition as claimed in claim 1, wherein: the transmission layer is used for transmitting signal data to the Web server, the Web server sorts the data and then transmits the data to the cable fault distance numerical calculation server, and the platform layer is used for calculating and analyzing the data from the Web server by a cable fault point midpoint traveling wave distance measurement algorithm of parameter optimization variational modal decomposition, and transmitting the result back to the Web server.
8. The cable fault point midpoint traveling wave ranging on-line positioning system based on current magnetic signals and parameter optimization variational modal decomposition as claimed in claim 1, wherein: and the application layer is used for displaying the diagnosis result on the user terminal through the Web server.
9. The cable fault point midpoint traveling wave ranging on-line positioning system based on current magnetic signals and parameter optimization variational modal decomposition as claimed in claim 1, wherein: three-phase current and voltage signals at two ends are coupled with each other, and decoupling is carried out by adopting a newly proposed phase-mode transformation matrix, wherein the phase-mode transformation matrix is as follows:
the phase-mode transformation calculation formula is as follows:
wherein u is a ,u b ,u c ,i a ,ib,i c Fault voltage and current travelling wave u on A, B and C phase lines 0 ,u α ,u β ,i 0 ,i α ,i β Respectively are the 0 mode, alpha mode and beta mode components of the voltage and current traveling wave.
10. The cable fault point midpoint traveling wave ranging on-line positioning system based on current magnetic signals and parameter optimization variational modal decomposition as claimed in claim 1, wherein: classifying the fault positions of the power cables:
a fault occurs ON the MO and a fault occurs ON the ON;
wherein, MO is the power cable left side, and ON is the power cable right side.
The velocity is calculated by the formula
The fault distance is calculated by the formula
Wherein t is 1 The moment when the travelling wave passes the midpoint for the first time, t 2 The moment t when the first traveling wave passes through the midpoint after being reflected by the bus M 3 The moment when the first traveling wave passes through the midpoint after being reflected by the bus N.
11. The cable fault point midpoint traveling wave ranging on-line positioning system based on current magnetic signals and parameter optimization variational modal decomposition as claimed in claim 4, wherein: and the cable fault distance numerical calculation server decomposes the traveling wave characteristics by using variational modal decomposition optimized by an Ulva-gull optimization algorithm, performs wave head calibration by using a Teager-Kaiser energy operator, and performs fault positioning by using the obtained time data.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116466181A (en) * | 2023-04-11 | 2023-07-21 | 特斯联科技集团有限公司 | System, method and storage medium for detecting fault artificial intelligence of buried cable |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116466181A (en) * | 2023-04-11 | 2023-07-21 | 特斯联科技集团有限公司 | System, method and storage medium for detecting fault artificial intelligence of buried cable |
| CN116466181B (en) * | 2023-04-11 | 2023-11-21 | 特斯联科技集团有限公司 | System, method and storage medium for detecting fault artificial intelligence of buried cable |
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