Power cable partial discharge positioning test simulation method and system

Abstract

The invention discloses a power cable partial discharge positioning test simulation method and system. The method comprises the steps that a multifunctional signal source simulates a partial discharge point to send out a first signal and a second signal at a preset time interval; transmitting the first signal through a first analog power cable, measuring the first signal through a first sensor arranged on the first analog power cable, and recording a first moment when the first signal is measured; transmitting a second signal through a second analog power cable, measuring the second signal through a second sensor arranged on the second analog power cable, and recording a second moment when the second signal is measured; and determining the position of the partial discharge point based on the difference between the first moment and the second moment. According to the power cable partial discharge positioning test simulation method and system, a partial discharge signal on a line is simulated without arranging a long-distance cable, and the position of a partial discharge point can be rapidly calculated through the time difference of the partial discharge pulse reaching the two ends of the cable.

Description

Technical Field

[0001] The present invention relates to the technical field of cable detection, and more specifically, to a method and system for simulating a partial discharge location test of a power cable. Background Art

[0002] High-voltage cables are an important part of the power system. The intelligent integrated high-voltage cable network operation comprehensive monitoring and management system is an effective means to ensure the safe operation of cables, enhance the power supply capacity of cables, improve the operation and management level of power cables, and improve the safety and stability of power grids. It is an important part of realizing the intelligentization of power grids. At present, the existing cable transmission capacity is constantly challenged. With the continuous advancement of the overhead line underground project, the intelligentization of power transmission and transformation is getting higher and higher. The problem of high-voltage power cable operation status monitoring is particularly prominent. Under normal circumstances, the operation status management of high-voltage cable lines is mainly based on regular inspections. Many insulation defects and potential faults cannot be discovered in time. At present, the offline detection of cables is gradually being converted to online monitoring to realize the identification and positioning of partial discharge types, timely forecast the insulation level of cable lines, and prevent sudden failures of high-voltage cables, which will be conducive to the reliable operation of cable networks.

[0003] Therefore, a technology is needed to realize the simulation technology of partial discharge location test of power cables. Summary of the invention

[0004] The technical solution of the present invention provides a power cable partial discharge location test simulation method and system to solve the problem of how to perform test simulation on power cable partial discharge location.

[0005] In order to solve the above problems, the present invention provides a power cable partial discharge location test simulation method, the method comprising:

[0006] The multifunctional signal source simulates the local discharge point to send out a first signal and a second signal at predetermined time intervals;

[0007] Transmitting the first signal through a first simulated power cable, measuring the first signal through a first sensor disposed on the first simulated power cable, and recording a first moment when the first signal is measured;

[0008] transmitting the second signal through a second simulated power cable, measuring the second signal through a second sensor disposed on the second simulated power cable, and recording a second time when the second signal is measured;

[0009] The location of the partial discharge point is determined based on the difference between the first time and the second time.

[0010] Preferably, the method further comprises: controlling the predetermined time interval and number of times of the first signal and the second signal sent by the multifunctional signal source by a control unit.

[0011] Preferably, it includes: the first signal is a partial discharge signal; the second signal is a partial discharge signal, a square wave signal or a sine wave signal, and the output signal can be switched according to different tests.

[0012] Preferably, the first simulated power cable and the second simulated power cable are both no longer than 1 meter.

[0013] Preferably, determining the location of the partial discharge point based on the difference between the first moment and the second moment includes:

[0014]

[0015] Among them, L AB is the cable length; v is the transmission speed of the partial discharge signal; t A is the first moment; t B This is the second moment.

[0016] Preferably, the predetermined time interval between the first signal and the second signal sent by the multifunctional signal source is: 1 microsecond, 2 microseconds, 5 microseconds, 10 microseconds or 20 microseconds.

[0017] Preferably, the multifunctional signal source sends the first signal and the second signal five times.

[0018] Based on another aspect of the present invention, the present invention provides a power cable partial discharge location test simulation system, the system comprising:

[0019] A multifunctional signal source, used for simulating a local discharge point to send out a first signal and a second signal at a predetermined time interval;

[0020] a first output channel, configured to transmit the first signal through a first simulated power cable, measure the first signal through a first sensor disposed on the first simulated power cable, and record a first moment when the first signal is measured;

[0021] a second output channel, for transmitting the second signal through a second simulated power cable, measuring the second signal through a second sensor disposed on the second simulated power cable, and recording a second time when the second signal is measured;

[0022] A control unit is used to determine the position of the partial discharge point based on the difference between the first moment and the second moment.

[0023] Preferably, it further comprises: the control unit is further used to control the predetermined time interval and number of times of the first signal and the second signal sent by the multifunctional signal source.

[0024] Preferably, it includes: the first signal is a partial discharge signal; the second signal is a partial discharge signal, a square wave signal or a sine wave signal, and the output signal can be switched according to different tests.

[0025] Preferably, the first simulated power cable and the second simulated power cable are both no longer than 1 meter.

[0026] Preferably, the control unit is used to determine the position of the partial discharge point based on the difference between the first moment and the second moment, wherein the calculation formula is:

[0027]

[0028] Among them, L AB is the cable length; v is the transmission speed of the partial discharge signal; t A is the first moment; t B This is the second moment.

[0029] Preferably, the predetermined time interval between the first signal and the second signal sent by the multifunctional signal source is: 1 microsecond, 2 microseconds, 5 microseconds, 10 microseconds or 20 microseconds.

[0030] Preferably, the multifunctional signal source sends the first signal and the second signal five times.

[0031] The technical solution of the present invention provides a method and system for simulating a local discharge location test of a power cable, wherein the method includes: simulating a local discharge point to send a first signal and a second signal at a predetermined time interval through a multifunctional signal source; transmitting the first signal through a first simulated power cable, measuring the first signal through a first sensor arranged at the first simulated power cable, and recording the first moment when the first signal is measured; transmitting the second signal through a second simulated power cable, measuring the second signal through a second sensor arranged at the second simulated power cable, and recording the second moment when the second signal is measured; determining the location of the local discharge point based on the difference between the first moment and the second moment. The present invention provides a method and system for simulating a local discharge location test of a power cable, which can simulate a local discharge signal on a line without the need to arrange a long-distance cable, and can quickly calculate the location of the local discharge point through the time difference of the local discharge pulse reaching both ends of the cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] A more complete understanding of exemplary embodiments of the present invention may be obtained by referring to the following drawings:

[0033] Figure 1 A flow chart of a power cable partial discharge location test simulation method according to a preferred embodiment of the present invention;

[0034] Figure 2 It is a structural diagram of a power cable partial discharge location test simulation device according to a preferred embodiment of the present invention;

[0035] Figure 3 It is a schematic diagram of the principle of a partial discharge location test for laying power cables according to a preferred embodiment of the present invention;

[0036] Figure 4 The present invention is a structural diagram of a power cable partial discharge location test simulation system according to a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0037] Now, exemplary embodiments of the present invention are described with reference to the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to disclose the present invention in detail and completely and to fully convey the scope of the present invention to those skilled in the art. The terms used in the exemplary embodiments shown in the accompanying drawings are not intended to limit the present invention. In the accompanying drawings, the same units / elements are marked with the same reference numerals.

[0038] Unless otherwise specified, the terms (including technical terms) used herein have the commonly understood meanings to those skilled in the art. In addition, it is understood that the terms defined in commonly used dictionaries should be understood to have the same meanings as those in the context of the relevant fields, and should not be understood as idealized or overly formal meanings.

[0039] Figure 1 The present invention is a flow chart of a power cable partial discharge location test simulation method according to a preferred embodiment of the present invention.

[0040] There are many types of power cable partial discharge detection and positioning equipment. Before they are put into use, they often need to be tested for performance. Their performance tests are mainly aimed at partial discharge detection functions, including signal sensitivity, linearity and anti-interference performance, but there is a lack of testing for the positioning function of the product. The main principle of its positioning function is as follows: Figure 3 As shown, the calculation formula for the location of the local discharge point is as follows:

[0041]

[0042] Among them, L PD is the location of the local discharge signal, L AB is the length of the cable between sensor A and sensor B, t Bis the time required for the partial discharge signal to be transmitted to sensor B, t A is the time required for the partial discharge signal to be transmitted to sensor A, and v is the speed at which the partial discharge signal propagates along the cable.

[0043] The present invention is known (t B -t A ) and v, L can be calculated PD Therefore, for the power cable partial discharge detection and positioning equipment, the positioning function test is mainly aimed at (t B -t A During the implementation process, the cable required for this real-type test is about 30 kilometers long, which consumes high manpower and material costs.

[0044] In view of the shortcomings or defects of the prior art, the present invention provides a power cable partial discharge positioning test simulation method, which can simulate the partial discharge signal on the line without the need to lay long-distance cables. The location of the partial discharge point can be quickly calculated through the time difference between the partial discharge pulse reaching the two ends of the cable.

[0045] Assuming the cable length is 30 km, the transmission speed of the partial discharge signal is 3×10 8 m / s, the calculation formula of partial discharge point is:

[0046]

[0047] like Figure 1 As shown, the present invention provides a power cable partial discharge location test simulation method, the method comprising:

[0048] Step 101: simulating a local discharge point to send out a first signal and a second signal at a predetermined time interval by a multifunctional signal source;

[0049] Preferably, the method further comprises: controlling, by a control unit, a predetermined time interval and number of times of the first signal and the second signal sent by the multifunctional signal source.

[0050] Preferably, it includes: the first signal is a partial discharge signal; the second signal is a partial discharge signal, a square wave signal or a sine wave signal, and the output signal can be switched according to different tests.

[0051] Preferably, the predetermined time interval between the first signal and the second signal sent by the multifunctional signal source is: 1 microsecond, 2 microseconds, 5 microseconds, 10 microseconds or 20 microseconds.

[0052] Preferably, the multifunctional signal source sends the first signal and the second signal five times.

[0053] The multifunctional signal source of the present invention simulates a local discharge point to send out a first local discharge signal and a second signal separated by a predetermined time interval;

[0054] The invention also comprises a signal source control unit which is connected to and controls the multifunctional signal source.

[0055] The signal source control unit of the present invention controls the time intervals at which the multifunctional signal source sends signals to the first output channel and the second output channel respectively.

[0056] The signal source control unit of the present invention controls the number of times the multifunctional signal source sends signals to the first output channel and the second output channel respectively.

[0057] Step 102: transmitting a first signal through a first simulated power cable, measuring the first signal through a first sensor provided on the first simulated power cable, and recording a first moment when the first signal is measured;

[0058] The first output channel of the present invention simulates a power cable and is connected to a channel multifunctional signal source to transmit a first partial discharge signal from the multifunctional signal source. The first sensor is arranged on the first output channel to measure the first partial discharge signal of the channel, and the first signal is a partial discharge signal.

[0059] Step 103: transmitting a second signal through a second simulated power cable, measuring the second signal through a second sensor disposed on the second simulated power cable, and recording a second time when the second signal is measured;

[0060] Preferably, the first simulated power cable and the second simulated power cable are both no longer than 1 meter.

[0061] The second output channel of the present invention simulates a power cable and is connected to the channel multi-function signal source to transmit a second signal from the multi-function signal source;

[0062] A second sensor is provided at the second output channel to measure a second signal of the channel,

[0063] In the power cable partial discharge location test simulation device of the present invention, the second signal of the channel is a partial discharge signal, a square wave signal or a sine wave signal, and the output signal can be switched according to different tests.

[0064] The first output channel and the second output channel of the present invention are both no longer than 1 meter.

[0065] Step 104: Determine the location of the partial discharge point based on the difference between the first moment and the second moment.

[0066] Preferably, determining the location of the partial discharge point based on the difference between the first moment and the second moment includes:

[0067]

[0068] Among them, L AB is the cable length; v is the transmission speed of the partial discharge signal; t A is the first moment; t B For the second moment.

[0069] The control unit of the present invention connects the first sensor and the second sensor to obtain a first moment when the first sensor collects a first local signal and a second moment when the second sensor collects a second signal.

[0070] The control unit of the present invention obtains the position of the simulated partial discharge point based on the difference between the first moment and the second moment.

[0071] In the present invention, a signal acquisition and display device is provided which is connected to a first output channel and a second output channel to display a first partial discharge signal and a second signal separated by a predetermined time interval.

[0072] The control unit of the present invention comprises a processor and a timer.

[0073] like Figure 2 As shown, a power cable partial discharge location test simulation method proposed by the present invention is based on a power cable partial discharge location test simulation device, and the test simulation device includes:

[0074] A multifunctional signal source, which simulates a partial discharge point to send out a first partial discharge signal and a second signal separated by a predetermined time interval,

[0075] a first output channel simulating a power cable and connected to a channel multi-function signal source to transmit a first partial discharge signal from the multi-function signal source,

[0076] A second output channel simulating a power cable and connected to a channel multi-function signal source to deliver a second signal from the multi-function signal source,

[0077] A first sensor is provided in a first output channel to measure a first partial discharge signal of the channel,

[0078] A second sensor is provided at the second output channel to measure a second signal of the channel,

[0079] A control unit is connected to the first sensor and the second sensor to obtain a first moment when the first sensor collects the first local signal and a second moment when the second sensor collects the second signal.

[0080] The present invention obtains the position of the simulated partial discharge point based on the difference between the first moment and the second moment. By obtaining the difference between the first moment and the second moment, the position of the simulated partial discharge point can be obtained accordingly, and the arrangement of the first output channel and the second output channel can avoid laying a 30km-level cable.

[0081] In a preferred embodiment of the power cable partial discharge location test simulation device of the present invention, it also includes a signal source control unit connected to and controlling the multifunctional signal source.

[0082] In a preferred embodiment of the channel power cable partial discharge location test simulation device, the channel signal source control unit controls the time intervals at which the multifunctional signal source sends signals to the first output channel and the second output channel respectively.

[0083] In a preferred embodiment of the power cable partial discharge location test simulation device of the present invention, the signal source control unit controls the number of times the multifunctional signal source sends signals to the first output channel and the second output channel respectively.

[0084] In a preferred embodiment of the power cable partial discharge location test simulation device of the present invention, the first signal is a partial discharge signal.

[0085] In a preferred embodiment of the power cable partial discharge location test simulation device of the present invention, the second signal is a partial discharge signal, a square wave signal or a sine wave signal, and the output signal can be switched for different tests.

[0086] In a preferred embodiment of the power cable partial discharge location test simulation device of the present invention, it also includes a signal acquisition and display device connected to the first output channel and the second output channel to display the first partial discharge signal and the second signal separated by a predetermined time interval.

[0087] In a preferred embodiment of the power cable partial discharge location test simulation device of the present invention, both the first output channel and the second output channel are no more than 1 meter.

[0088] In a preferred embodiment of the power cable partial discharge location test simulation device of the present invention, the control unit includes a processor and a timer.

[0089] In a preferred embodiment of the power cable partial discharge location test simulation device of the present invention, the multifunctional signal source sends a total of 5 groups of signals to the first output channel and the second output channel respectively, and the predetermined time intervals can be set to 1 microsecond, 2 microseconds, 5 microseconds, 10 microseconds and 20 microseconds respectively. Further, multiple measurements such as 5 measurement results are obtained to obtain whether the power cable partial discharge location function can be realized.

[0090] In a preferred embodiment of the power cable partial discharge location test simulation device of the present invention, it also includes a signal acquisition and display device connected to the first output channel and the second output channel to display the first partial discharge signal and the second signal separated by a predetermined time interval.

[0091] In a preferred embodiment of the power cable partial discharge location test simulation device of the present invention, the signal acquisition and display device includes a liquid crystal screen.

[0092] In a preferred embodiment of the power cable partial discharge location test simulation device of the present invention, the control unit includes a processor and a timer.

[0093] In the present invention, the multifunctional signal source sends out two partial discharge signals through two output channels successively, and the interval time of the two output signals is adjusted according to the positioning accuracy required by the test. The sensor of the power cable partial discharge positioning and measuring device is placed on the line, and the device can output partial discharge signals, square wave signals, and sine wave signals, and the output signals can be switched for different tests.

[0094] In the present invention, the first output channel and the second output channel are arranged in parallel to avoid introducing additional time delay into any output channel, so as to ensure the accuracy of the present invention.

[0095] Figure 4 The present invention is a structural diagram of a power cable partial discharge location test simulation system according to a preferred embodiment of the present invention.

[0096] like Figure 4 As shown, the present invention provides a power cable partial discharge location test simulation system, the system comprising:

[0097] A multifunctional signal source 401, used for simulating a local discharge point to send out a first signal and a second signal at a predetermined time interval;

[0098] The first output channel 402 is used to transmit a first signal through a first simulated power cable, measure the first signal through a first sensor provided on the first simulated power cable, and record a first moment when the first signal is measured;

[0099] The second output channel 403 is used to transmit a second signal through a second simulated power cable, measure the second signal through a second sensor provided on the second simulated power cable, and record a second time when the second signal is measured;

[0100] The control unit 404 is configured to determine the location of the partial discharge point based on the difference between the first moment and the second moment.

[0101] Preferably, the system further comprises: a control unit 404, further configured to control the predetermined time interval and number of times of the first signal and the second signal sent by the multifunctional signal source.

[0102] Preferably, it includes: the first signal is a partial discharge signal; the second signal is a partial discharge signal, a square wave signal or a sine wave signal, and the output signal can be switched according to different tests.

[0103] Preferably, the first simulated power cable and the second simulated power cable are both no longer than 1 meter.

[0104] Preferably, the control unit is used to determine the position of the partial discharge point based on the difference between the first moment and the second moment, wherein the calculation formula is:

[0105]

[0106] Among them, L AB is the cable length; v is the transmission speed of the partial discharge signal; t A is the first moment; t B For the second moment.

[0107] Preferably, the predetermined time interval between the first signal and the second signal sent by the multifunctional signal source is: 1 microsecond, 2 microseconds, 5 microseconds, 10 microseconds or 20 microseconds.

[0108] Preferably, the multifunctional signal source sends the first signal and the second signal five times.

[0109] The present invention proposes a power cable partial discharge location test simulation method, which comprises the following steps:

[0110] The simulated partial discharge point sends a first partial discharge signal and a second partial discharge signal separated by a predetermined time interval,

[0111] Simulating a power cable and connecting a channel multi-function signal source to transmit a first partial discharge signal from the multi-function signal source,

[0112] Simulates a power cable and connects a channel multi-function signal source to transmit a second signal from the multi-function signal source,

[0113] Measuring the first partial discharge signal,

[0114] Measure the second signal,

[0115] A first time instant at which the first sensor collects the first local signal and a second time instant at which the second sensor collects the second signal are obtained.

[0116] The method of the present invention further comprises:

[0117] The position of the simulated partial discharge point is obtained based on the difference between the first time instant and the second time instant.

[0118] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes. The schemes in the embodiments of the present invention may be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0119] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0120] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0121] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0122] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0123] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

[0124] The invention has been described above with reference to a few embodiments. However, it is readily apparent to a person skilled in the art that other embodiments than the ones disclosed above are equally within the scope of the invention, as defined by the appended patent claims.

[0125] Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to "a / / the [means, component, etc.]" are to be openly interpreted as at least one instance of a means, component, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not necessarily have to be performed in the exact order disclosed, unless explicitly stated otherwise.

Claims

1. A method for simulating a partial discharge location test of a power cable, the method comprising: The multifunctional signal source simulates the local discharge point to send out a first signal and a second signal at predetermined time intervals; Transmitting the first signal through a first simulated power cable, measuring the first signal through a first sensor disposed on the first simulated power cable, and recording a first moment when the first signal is measured; transmitting the second signal through a second simulated power cable, measuring the second signal through a second sensor disposed on the second simulated power cable, and recording a second time when the second signal is measured; The location of the partial discharge point is determined based on the difference between the first time and the second time.

2. The method according to claim 1, further comprising: The predetermined time interval and number of times of the first signal and the second signal sent by the multifunctional signal source are controlled by a control unit.

3. The method according to claim 1, comprising: The first signal is a partial discharge signal; the second signal is a partial discharge signal, a square wave signal or a sine wave signal, and the output signal is switched according to different tests. 4 . The method according to claim 1 , wherein the first simulated power cable and the second simulated power cable are both no longer than 1 meter.

5. The method according to claim 1, wherein determining the location of the partial discharge point based on the difference between the first moment and the second moment comprises: Among them, L AB is the cable length; v is the transmission speed of the partial discharge signal; t A is the first moment; t B This is the second moment. 6 . The method according to claim 1 , wherein the predetermined time interval between the first signal and the second signal sent by the multifunctional signal source is: 1 microsecond, 2 microseconds, 5 microseconds, 10 microseconds or 20 microseconds.

7. The method according to claim 2, wherein the multifunctional signal source sends the first signal and the second signal five times.

8. A power cable partial discharge location test simulation system, the system comprising: A multifunctional signal source, used for simulating a local discharge point to send out a first signal and a second signal at a predetermined time interval; a first output channel, configured to transmit the first signal through a first simulated power cable, measure the first signal through a first sensor disposed on the first simulated power cable, and record a first moment when the first signal is measured; a second output channel, for transmitting the second signal through a second simulated power cable, measuring the second signal through a second sensor disposed on the second simulated power cable, and recording a second time when the second signal is measured; A control unit is used to determine the position of the partial discharge point based on the difference between the first moment and the second moment.

9. The system according to claim 8, further comprising: The control unit is further used to control the predetermined time interval and number of times of the first signal and the second signal sent by the multifunctional signal source.

10. The system according to claim 8, comprising: The first signal is a partial discharge signal; the second signal is a partial discharge signal, a square wave signal or a sine wave signal, and the output signal is switched according to different tests.

11. The system of claim 8, wherein the first simulated power cable and the second simulated power cable are each no longer than 1 meter.

12. The system according to claim 8, wherein the control unit is configured to determine the location of the partial discharge point based on the difference between the first moment and the second moment, wherein the calculation formula is: in, L AB is the cable length; v is the transmission speed of the partial discharge signal; t A is the first moment; t B This is the second moment.

13. The system according to claim 8, wherein the predetermined time interval between the first signal and the second signal sent by the multifunctional signal source is 1 microsecond, 2 microseconds, 5 microseconds, 10 microseconds or 20 microseconds.

14. The system according to claim 9, wherein the multifunctional signal source sends the first signal and the second signal five times.

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