Cable partial discharge detection positioning system and method based on synchronization pulse and time compensation

Abstract

This application discloses a cable partial discharge detection and location system and method based on synchronous pulse and time compensation, relating to the field of cable partial discharge detection and location technology. The system includes a host computer and multiple detection and location devices. The host computer is responsible for marking the detection and location devices and identifying the master and slave devices. The master device generates a first synchronous compensation pulse signal on the cable shield grounding wire according to a synchronous compensation command; the slave device generates a second synchronous compensation pulse signal based on this signal. The master device determines the timing based on the two synchronous compensation pulse signals, and the host computer calculates the compensation time for the slave device based on the timing. The master and slave devices perform time compensation on the partial discharge signal acquired by the slave device according to the synchronous acquisition and location command from the host computer; the host computer determines the cable partial discharge location based on the partial discharge signals acquired by the master and slave devices. This application improves the time synchronization accuracy of partial discharge signal acquisition between the master and slave devices, thereby improving the location accuracy of the partial discharge point.

Description

Technical Field

[0001] This application relates to the field of cable partial discharge detection and location technology, and in particular to a cable partial discharge detection and location system and method based on synchronous pulse and time compensation. Background Technology

[0002] In power systems, the operating status of power cables is crucial to the stability of power transmission. Partial discharge location provides clear guidance for cable maintenance. Currently, in cable handover testing and live-line monitoring, multiple detection and location devices are often deployed along a single cable line to detect and locate partial discharge using the double-end method. The double-end method is a technological trend due to its high accuracy and reliable principle; however, it requires high-precision time synchronization at both ends of the cable to determine the absolute time of the partial discharge pulse arrival at each end.

[0003] In existing technologies, cable distributed partial discharge detection and positioning devices often employ GPS, BeiDou, or fiber optic synchronization. However, GPS or BeiDou signals are susceptible to weather and operating environment fluctuations, resulting in significant variations in synchronization accuracy. Furthermore, GPS or BeiDou signals can only be received outdoors in unobstructed conditions, and indoor cable terminal joint detection often fails to receive GPS or BeiDou signals, limiting its application environment. Fiber optic synchronization is also problematic due to the difficulty and high cost of direct burial of cables. In summary, existing dual-end methods suffer from poor reliability, accuracy, and environmental limitations in practical engineering applications due to limitations in synchronization methods (unstable satellite signals and difficult fiber optic deployment). Summary of the Invention

[0004] The purpose of this application is to provide a cable partial discharge detection and positioning system and method based on synchronization pulse and time compensation, which can improve the time synchronization accuracy between detection points and realize accurate detection and positioning of distributed partial discharge in cables.

[0005] To achieve the above objectives, this application provides the following solution: This application provides a cable partial discharge detection and location system based on synchronous pulse and time compensation, comprising: The host computer and multiple detection and positioning devices.

[0006] The host computer is used to mark adjacent detection and positioning devices within the target area and to determine the master and slave devices.

[0007] The host is used for: According to the synchronization compensation command output by the host computer, a first synchronization compensation pulse signal is generated on the shielding grounding wire of the cable in the target area, and a second synchronization compensation pulse signal generated by the slave device according to the first synchronization compensation pulse signal is received.

[0008] The timing time is determined based on the first synchronization compensation pulse signal and the second synchronization compensation pulse signal, and then sent to the host computer.

[0009] The host computer is also used to determine the compensation time based on the timing time, and output periodic synchronous acquisition and positioning commands after the compensation time is determined.

[0010] The host computer is also configured to, upon receiving a periodic synchronous acquisition and positioning command output by the host computer, generate a first synchronous acquisition pulse signal on the shielded grounding wire of the cable within the target area, and acquire a first partial discharge signal on the shielded grounding wire of the cable within the target area acquired under the first synchronous acquisition pulse signal.

[0011] The slave device is used for: Based on the first synchronous acquisition pulse signal and the compensation time, a compensation interval and a second synchronous acquisition pulse signal are generated, and a second partial discharge signal on the shield grounding wire of the cable in the target area acquired under the compensation interval and a third partial discharge signal on the shield grounding wire of the cable in the target area acquired under the second synchronous acquisition pulse signal are obtained; the next moment after the last moment corresponding to the second partial discharge signal is the first moment corresponding to the third partial discharge signal.

[0012] The host computer is also used to determine the location of partial discharge of the cable within the target area based on the first partial discharge signal, the second partial discharge signal, and the third partial discharge signal.

[0013] Secondly, this application provides a method for detecting and locating partial discharge in cables based on synchronization pulses and time compensation, including: The host computer marks adjacent detection and positioning devices within the target area to identify the master and slave devices.

[0014] The host computer, according to the synchronization compensation command output by the host computer, generates a first synchronization compensation pulse signal on the shield grounding wire of the cable in the target area, and receives a second synchronization compensation pulse signal generated by the slave computer according to the first synchronization compensation pulse signal.

[0015] The timing time is determined based on the first synchronization compensation pulse signal and the second synchronization compensation pulse signal, and then sent to the host computer.

[0016] The host computer determines the compensation time based on the timing time, and outputs periodic synchronous acquisition and positioning commands after the compensation time is determined.

[0017] When the host computer receives the periodic synchronous acquisition and positioning command output by the host computer, it excites a first synchronous acquisition pulse signal on the shielding grounding wire of the cable in the target area, and acquires the first partial discharge signal on the shielding grounding wire of the cable in the target area acquired under the first synchronous acquisition pulse signal.

[0018] The slave device generates a compensation interval and a second synchronous acquisition pulse signal based on the first synchronous acquisition pulse signal and the compensation time. It then acquires a second partial discharge signal on the shielded grounding wire of the cable within the target area acquired under the compensation interval and a third partial discharge signal on the shielded grounding wire of the cable within the target area acquired under the second synchronous acquisition pulse signal. The time following the last moment corresponding to the second partial discharge signal is the first moment corresponding to the third partial discharge signal.

[0019] The host computer determines the location of partial discharge in the cable within the target area based on the first partial discharge signal, the second partial discharge signal, and the third partial discharge signal.

[0020] According to the specific embodiments provided in this application, this application has the following technical effects: 1. By setting up a host computer and multiple detection and positioning devices, multiple detection and positioning devices are arranged on a single cable line, with one device placed at each intermediate joint. The detection and positioning devices inject synchronous pulse signals into the shielding grounding wire of the cable joint. By detecting the high-frequency partial discharge signal on the shielding grounding wire of the intermediate cable joint, the partial discharge condition of the cable is detected and located. For short-distance or long-distance cable lines with multiple intermediate joints, no other equipment is needed. The method of injecting synchronous pulse signals into the shielding grounding wire of the cable joint as the synchronous acquisition signal can effectively solve problems such as synchronous signal attenuation or oscillation. At the same time, by using synchronous pulse signals as the synchronous acquisition signal, the synchronization method is no longer affected by weather and operating environment for different cable detection and positioning environments, solving the problem of limited use environment and improving the reliability of partial discharge detection and positioning.

[0021] 2. Each detection and positioning device can both generate pulse signals and receive and process pulse signals. The detection and positioning device can be set through a host computer, flexibly determining the master and slave devices, which greatly improves the flexibility and applicability of system operation.

[0022] 3. The detection and positioning device uses the round-trip time of a pulse signal to calculate the synchronization time difference between the master and slave devices. This time difference is then compensated for by the slave device, enabling both the master and slave devices to upload partial discharge signal data with synchronized timing to the host computer. The host computer then performs positioning analysis based on the synchronously acquired partial discharge signal data. By triggering the detection and positioning device with a pulse signal to acquire data and compensating for the synchronization time difference with the slave device, the time synchronization accuracy between the master and slave devices at the detection points is improved, achieving precise detection and positioning of distributed partial discharge in cables. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 A schematic diagram of the structure of a detection and positioning device for a cable partial discharge detection and positioning system based on synchronization pulse and time compensation, provided in an embodiment of this application; Figure 2 A flowchart of a cable partial discharge detection and location method based on synchronization pulse and time compensation provided in an embodiment of this application; Figure 3 The flowchart illustrates a cable partial discharge detection and location method based on synchronization pulse and time compensation, which is provided in another embodiment of this application. Detailed Implementation

[0025] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0026] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] In one exemplary embodiment, a cable partial discharge detection and positioning system based on synchronous pulse and time compensation is provided. The system includes a host computer and multiple detection and positioning devices.

[0028] The host computer is used to mark adjacent detection and positioning devices within the target area and to determine the master and slave devices.

[0029] The host is used for: According to the synchronization compensation command output by the host computer, a first synchronization compensation pulse signal is generated on the shielding grounding wire of the cable in the target area, and a second synchronization compensation pulse signal generated by the slave device according to the first synchronization compensation pulse signal is received.

[0030] The timing time is determined based on the first synchronization compensation pulse signal and the second synchronization compensation pulse signal, and then sent to the host computer.

[0031] The host computer is also used to determine the compensation time based on the timing time, and output periodic synchronous acquisition and positioning commands after the compensation time is determined.

[0032] The host computer is also configured to, upon receiving a periodic synchronous acquisition and positioning command output by the host computer, generate a first synchronous acquisition pulse signal on the shielded grounding wire of the cable within the target area, and acquire a first partial discharge signal on the shielded grounding wire of the cable within the target area acquired under the first synchronous acquisition pulse signal.

[0033] The slave device is used for: Based on the first synchronous acquisition pulse signal and the compensation time, a compensation interval and a second synchronous acquisition pulse signal are generated, and a second partial discharge signal on the shield grounding wire of the cable in the target area acquired under the compensation interval and a third partial discharge signal on the shield grounding wire of the cable in the target area acquired under the second synchronous acquisition pulse signal are obtained; the next moment after the last moment corresponding to the second partial discharge signal is the first moment corresponding to the third partial discharge signal. The host computer is also used to determine the location of partial discharge in the cable within the target area based on the first partial discharge signal, the second partial discharge signal, and the third partial discharge signal. The cable partial discharge detection and location system based on synchronous pulse and time compensation provided in this application has the following effects: 1. By deploying multiple detection and positioning devices along the cable line and injecting a synchronous pulse signal into the shielding grounding wire of the cable joint as a synchronous acquisition signal, the attenuation of the synchronous signal and the influence of environmental factors are avoided, thereby improving the reliability of detection.

[0034] 2. Each detection and positioning device can both excite pulse signals and receive and process them. The host computer can flexibly determine the master and slave devices, improving the system's operational flexibility and applicability.

[0035] 3. The synchronization time difference between the master and slave devices is measured by the round-trip time of the pulse signal and compensated to the slave device. This enables the master and slave devices to upload partial discharge signal data with the same time to the host computer for positioning analysis, thereby improving the time synchronization accuracy and realizing accurate detection and positioning of distributed partial discharge in cables.

[0036] In one exemplary embodiment, the slave device is configured to: Based on the first synchronous acquisition pulse signal and the compensation time, a compensation interval and a second synchronous acquisition pulse signal are generated. The compensation interval is the compensation time obtained by timing the first synchronous compensation pulse signal and the second synchronous compensation pulse signal of the host computer. When the host computer issues a periodic synchronous acquisition and positioning command, the synchronous pulse unit of the slave computer also receives the first synchronous acquisition pulse signal excited by the host computer, and sends the received first synchronous acquisition pulse signal to the intelligent synchronous compensation module of the slave computer. The intelligent synchronous compensation module of the slave computer processes the first synchronous acquisition pulse signal into a second synchronous acquisition pulse signal, and sends the second synchronous acquisition pulse signal to the detection and positioning synchronous acquisition module of the slave computer. It then acquires the second partial discharge signal on the shield grounding wire of the cable in the target area acquired under the compensation interval and the third partial discharge signal on the shield grounding wire of the cable in the target area acquired under the second synchronous acquisition pulse signal. The next moment after the last moment corresponding to the second partial discharge signal is the first moment corresponding to the third partial discharge signal.

[0037] In an exemplary embodiment, for the purpose of determining the target region, the host computer is used to: The target area is determined based on the fourth partial discharge signal sent by each detection and positioning device; the target area is the location range of the partial discharge point of the cable.

[0038] The fourth partial discharge signal is a partial discharge signal collected by each detection and positioning device according to the signal acquisition command sent by the host computer.

[0039] The detection and positioning device provided in this application has two operating modes: a detection mode and a positioning mode. Generally, in the detection mode, an abnormal partial discharge signal is detected. Based on the abnormal partial discharge signal, the location range of the partial discharge signal (i.e., the target area) is determined. The host computer marks adjacent detection and positioning devices within the location range of the partial discharge signal to identify the master and slave devices. Then, the host computer switches the detection and positioning device to the positioning mode. In the positioning mode, the detection and positioning device uses the round-trip time of the pulse signal to calculate the synchronization time difference between the master and slave devices, and then further determines the location of the partial discharge in the cable within the target area based on the time difference.

[0040] In one exemplary embodiment, the host computer is used for system control and communicates with each detection and positioning device via a wireless network to receive and process the data transmitted by the detection and positioning devices; each detection and positioning device is deployed at different detection positions along the entire cable line being tested.

[0041] In one exemplary embodiment, such as Figure 1 As shown, each of the detection and positioning devices includes a detection and positioning synchronous acquisition module, an intelligent synchronous compensation module, a synchronous pulse unit, and a partial discharge coupling unit.

[0042] The detection, positioning, and synchronous acquisition module is connected to the intelligent synchronous compensation module, the partial discharge coupling unit, and the host computer, respectively.

[0043] The intelligent synchronization compensation module is connected to the synchronization pulse unit.

[0044] The synchronization pulse unit and the partial discharge coupling unit are used to connect to the shielding ground wire of the cable.

[0045] The detection and positioning synchronous acquisition module is used for partial discharge signal acquisition and processing. It communicates with the host computer via a wireless network and uploads the acquired and filtered data to the host computer for detection and positioning calculation.

[0046] The intelligent synchronization compensation module is used to provide pulse trigger signals to the synchronization pulse unit. At the same time, it also receives and processes the pulse signals to provide signals to the detection and positioning synchronization acquisition module. The detection and positioning synchronization acquisition module identifies the signals provided by the intelligent synchronization compensation module.

[0047] During system operation, both the synchronization pulse unit and the partial discharge coupling unit are installed on the same shielded grounding wire of the cable. Specifically, the synchronization pulse unit is inserted through-hole and clipped onto the shielded grounding wire of the cable insulation joint, positioned on the side furthest from the grounding section. The synchronization pulse unit is used to excite and receive synchronization pulse signals. The partial discharge coupling unit is inserted through-hole and clipped onto the shielded grounding wire of the cable insulation joint, positioned on the side closest to the grounding section. The partial discharge coupling unit outputs the high-frequency partial discharge signal coupled onto the shielded grounding wire to the detection and positioning synchronization acquisition module. The detection and positioning synchronization acquisition module acquires and filters the high-frequency partial discharge signal.

[0048] In an exemplary embodiment, the host computer is used to control the partial discharge coupling unit of the host computer to continuously collect partial discharge signals on the shielding ground wire of the cable within the target area after receiving a periodic synchronous acquisition and positioning command output by the host computer. The slave device is used to continuously collect partial discharge signals on the shielded grounding wire of the cable within the target area after receiving the periodic synchronous acquisition and positioning command output by the host computer, and in conjunction with time compensation, control the partial discharge coupling unit of the slave device.

[0049] In an exemplary embodiment, the host's detection, positioning, and synchronization acquisition module is used to control the host's intelligent synchronization compensation module to generate a first synchronization compensation signal according to the synchronization compensation instruction from the host computer.

[0050] The master's synchronization pulse unit is used to generate a first synchronization compensation pulse signal on the shielded grounding wire of the cable in the target area according to the first synchronization compensation signal, and to receive a second synchronization compensation pulse signal generated by the slave according to the first synchronization compensation pulse signal.

[0051] In an exemplary embodiment, the host's synchronization pulse unit is further configured to send the first synchronization compensation pulse signal to the host's intelligent synchronization compensation module.

[0052] The intelligent synchronization compensation module of the host is used to process the first synchronization compensation pulse signal into a timing signal and send the timing signal to the detection and positioning synchronization acquisition module of the host.

[0053] The host's detection, positioning, and synchronous acquisition module is used to start timing when it receives the timing signal.

[0054] The synchronization pulse unit of the host is also used to receive the second synchronization compensation pulse signal and send the second synchronization compensation pulse signal to the intelligent synchronization compensation module of the host.

[0055] The intelligent synchronization compensation module of the host is used to process the second synchronization compensation pulse signal into a stop timing signal and send the stop timing signal to the detection and positioning synchronization acquisition module of the host.

[0056] The detection, positioning, and synchronization acquisition module of the host computer is used to stop timing and determine the timing time when it receives the stop timing signal; and to send the timing time to the host computer, which determines the compensation time based on the timing time.

[0057] In an exemplary embodiment, the host's detection, positioning, and synchronization acquisition module is used to control the host's intelligent synchronization compensation module to generate a first synchronization acquisition signal when it receives a periodic synchronization acquisition and positioning command output by the host computer.

[0058] The host's synchronization pulse unit is used to excite a first synchronization acquisition pulse signal on the shielded grounding wire of the cable in the target area according to the first synchronization acquisition signal, and to send the first synchronization acquisition pulse signal to the host's intelligent synchronization compensation module.

[0059] The intelligent synchronization compensation module of the host is used to process the first synchronization acquisition pulse signal into a first acquisition signal and send the first acquisition signal to the detection and positioning synchronization acquisition module of the host.

[0060] The detection and positioning synchronous acquisition module of the host is used to acquire the partial discharge signal acquired by the partial discharge coupling unit of the host, and to filter the acquired partial discharge signal based on the first acquisition signal to obtain the first partial discharge signal on the shield grounding wire of the cable in the target area acquired under the first acquisition signal.

[0061] As an example, when the host's detection and positioning synchronous acquisition module is in the positioning synchronous trigger acquisition state, based on the first acquisition signal, it performs threshold filtering on the partial discharge signal sent by the host's partial discharge coupling unit: signals with amplitudes greater than a preset threshold are identified as valid partial discharge signals, and mixed noise interference is eliminated, thereby obtaining the first partial discharge signal on the shield grounding wire of the cable in the target area acquired under the first synchronous acquisition pulse signal, and sending the first partial discharge signal to the host computer.

[0062] In an exemplary embodiment, the slave device's synchronization pulse unit is used to receive the first synchronization compensation pulse signal and send the first synchronization compensation pulse signal to the slave device's intelligent synchronization compensation module.

[0063] The slave device's intelligent synchronization compensation module is used to convert the first synchronization compensation pulse signal into a second synchronization compensation signal through a fixed time delay.

[0064] The slave device's synchronization pulse unit is used to generate a second synchronization compensation pulse signal on the shielded grounding wire of the cable within the target area according to the second synchronization compensation signal.

[0065] In an exemplary embodiment, the slave device's synchronization pulse unit is used to send the received first synchronization acquisition pulse signal to the slave device's intelligent synchronization compensation module.

[0066] The slave device's intelligent synchronization compensation module is used to process the first synchronization acquisition pulse signal into a second acquisition signal, and send the second acquisition signal to the slave device's detection and positioning synchronization acquisition module.

[0067] In an exemplary embodiment, the slave device's detection, positioning, and synchronization acquisition module is used to generate a compensation interval based on the second acquisition signal and the compensation time sent by the host computer.

[0068] The slave device's detection and positioning synchronous acquisition module is also used to acquire the partial discharge signal acquired by the slave device's partial discharge coupling unit, and to filter the acquired partial discharge signal based on the second acquisition signal and the compensation interval to obtain the second partial discharge signal on the shield grounding wire of the cable in the target area acquired under the compensation interval and the third partial discharge signal on the shield grounding wire of the cable in the target area acquired under the second acquisition signal.

[0069] Based on the same inventive concept, embodiments of this application provide a method for detecting and locating partial discharge in cables using a synchronization pulse and time compensation approach, such as... Figure 2 As shown, the specific steps include the following: Step 201: The host computer marks the adjacent detection and positioning devices in the target area to determine the master and slave devices.

[0070] Step 202: The host computer, according to the synchronization compensation instruction output by the host computer, excites a first synchronization compensation pulse signal on the shielding grounding wire of the cable in the target area, and receives a second synchronization compensation pulse signal excited by the slave computer according to the first synchronization compensation pulse signal.

[0071] Step 203: Determine the timing time based on the first synchronization compensation pulse signal and the second synchronization compensation pulse signal, and send it to the host computer.

[0072] Step 204: The host computer determines the compensation time based on the timing time, and outputs periodic synchronous acquisition and positioning commands after the compensation time is determined.

[0073] Step 205: When the host computer receives the periodic synchronous acquisition and positioning command output by the host computer, it excites a first synchronous acquisition pulse signal on the shielding grounding wire of the cable in the target area, and acquires the first partial discharge signal on the shielding grounding wire of the cable in the target area acquired under the first synchronous acquisition pulse signal.

[0074] Step 206: The slave device generates a compensation interval and a second synchronous acquisition pulse signal based on the first synchronous acquisition pulse signal and the compensation time. It then acquires a second partial discharge signal on the shielded grounding wire of the cable within the target area acquired under the compensation interval and a third partial discharge signal on the shielded grounding wire of the cable within the target area acquired under the second synchronous acquisition pulse signal. The next moment after the last moment corresponding to the second partial discharge signal is the first moment corresponding to the third partial discharge signal.

[0075] Step 207: The host computer determines the partial discharge location of the cable within the target area based on the first partial discharge signal, the second partial discharge signal, and the third partial discharge signal.

[0076] In another exemplary embodiment, a method for detecting and locating partial discharge in cables based on synchronization pulses and time compensation is provided, such as... Figure 3 As shown, the specific steps include: Step 301: The host computer sets the working mode of all detection and positioning devices to detection mode; all detection and positioning devices collect partial discharge signals according to the signal acquisition instructions sent by the host computer to obtain the fourth partial discharge signal; the host computer determines the location range of the abnormal partial discharge signal based on the fourth partial discharge signal to obtain the target area.

[0077] Step 302: The host computer marks the adjacent detection and positioning devices in the target area, identifies the master and slave devices, and sets the working mode of the master and slave devices to positioning mode.

[0078] Step 303: The host computer sends a synchronization compensation command to the host computer. The host computer's detection, positioning, and synchronization acquisition module controls the host computer's intelligent synchronization compensation module to generate a first synchronization compensation signal according to the host computer's synchronization compensation command. The host computer's synchronization pulse unit excites a first synchronization compensation pulse signal on the shielded grounding wire of the cable in the target area according to the first synchronization compensation signal.

[0079] Step 304: The synchronization pulse unit of the host sends the first synchronization compensation pulse signal to the intelligent synchronization compensation module of the host; the intelligent synchronization compensation module of the host processes the first synchronization compensation pulse signal into a timing signal and sends the timing signal to the detection and positioning synchronization acquisition module of the host; when the detection and positioning synchronization acquisition module of the host receives the timing signal, it starts timing.

[0080] Step 305: The slave device's synchronization pulse unit receives the first synchronization compensation pulse signal and sends it to the slave device's intelligent synchronization compensation module; the slave device's intelligent synchronization compensation module converts the first synchronization compensation pulse signal into a second synchronization compensation signal after a fixed time delay; the slave device's synchronization pulse unit excites the second synchronization compensation pulse signal on the shielding grounding wire of the cable in the target area according to the second synchronization compensation signal.

[0081] Step 306: The host's synchronization pulse unit receives the second synchronization compensation pulse signal and sends it to the host's intelligent synchronization compensation module; the host's intelligent synchronization compensation module processes the second synchronization compensation pulse signal into a stop timing signal and sends it to the host's detection and positioning synchronization acquisition module; when the host's detection and positioning synchronization acquisition module receives the stop timing signal, it stops timing, determines the timing time, and sends the timing time to the host computer; the host computer determines the compensation time based on the timing time and outputs periodic synchronization acquisition and positioning commands after the compensation time is determined.

[0082] The compensation time is determined using the following formula: T comp =（T total -Tfixed ） / 2 .

[0083] in, T comp Indicates the compensation period; T total Indicates the time of the time; T fixed This indicates a fixed time delay.

[0084] The fixed delay is an inherent, calibrable system delay of the intelligent synchronization compensation module in the detection and positioning device, obtainable through factory calibration. This fixed delay is unaffected by factors such as cable length and environment; it is solely the response time of the intelligent synchronization compensation module. In summary, the compensation time is the one-way propagation time of the compensation pulse signal in the cable, used for subsequent time synchronization compensation. Meanwhile, the cable length between the master and slave devices is known. L The propagation speed of a pulse signal in a cable can be calculated by compensating for the time. V .

[0085] The formula for calculating the propagation speed is: V=L / T comp .

[0086] in, V Describes the propagation speed of a pulse signal in a cable; L Describe the cable length between the master and slave devices.

[0087] Step 307: Upon receiving a periodic synchronous acquisition and positioning command from the host computer, the host computer controls its partial discharge coupling unit to continuously acquire partial discharge signals on the shielded grounding wire of the cable within the target area; and sends the acquired partial discharge signals to the host computer's detection, positioning, and synchronous acquisition module. Upon receiving the periodic synchronous acquisition and positioning command from the host computer, the slave computer, in conjunction with time compensation, controls its partial discharge coupling unit to continuously acquire partial discharge signals on the shielded grounding wire of the cable within the target area, and sends the acquired partial discharge signals to the slave computer's detection, positioning, and synchronous acquisition module.

[0088] Step 308: The host computer sends a periodic synchronous acquisition and positioning command to the host computer. The host computer's detection and positioning synchronous acquisition module receives the synchronous acquisition and positioning command from the host computer and controls the host computer's intelligent synchronous compensation module to generate a first synchronous acquisition signal. The host computer's synchronous pulse unit excites a first synchronous acquisition pulse signal on the shielded grounding wire of the cable within the target area based on the first synchronous acquisition signal, and sends the first synchronous acquisition pulse signal to the host computer's intelligent synchronous compensation module. The host computer's intelligent synchronous compensation module processes the first synchronous acquisition pulse signal into a first acquisition signal and sends the first acquisition signal to the host computer's detection and positioning synchronous acquisition module. After receiving the first acquisition signal, the host computer's detection and positioning synchronous acquisition module enters a positioning synchronous trigger acquisition state. In the positioning synchronous trigger acquisition state, based on the first acquisition signal, the host computer's detection and positioning synchronous acquisition module filters the partial discharge signal sent by the host computer's partial discharge coupling unit to obtain the first partial discharge signal on the shielded grounding wire of the cable within the target area acquired under the first synchronous acquisition pulse signal, and sends the first partial discharge signal to the host computer. Simultaneously, it waits for the next first acquisition signal.

[0089] Step 309: The slave device's synchronization pulse unit sends the received first synchronization acquisition pulse signal to the slave device's intelligent synchronization compensation module; the slave device's intelligent synchronization compensation module processes the first synchronization acquisition pulse signal into a second acquisition signal and sends the second acquisition signal to the slave device's detection and positioning synchronization acquisition module; after receiving the second acquisition signal, the slave device's detection and positioning synchronization acquisition module enters the positioning synchronization trigger acquisition state and generates a compensation interval based on the second acquisition signal and the compensation time sent by the host computer; in the positioning synchronization trigger acquisition state, the slave device's detection and positioning synchronization acquisition module filters the partial discharge signals sent by the slave device's partial discharge coupling unit based on the second synchronization acquisition signal and the compensation interval, obtaining a second partial discharge signal on the shielded grounding wire of the cable in the target area acquired under the compensation interval and a third partial discharge signal on the shielded grounding wire of the cable in the target area acquired under the second synchronization acquisition signal, and sends the second and third partial discharge signals to the host computer. Simultaneously, it waits for the next second acquisition signal.

[0090] Step 310: The host computer determines the partial discharge location of the cable under test based on the first partial discharge signal, the second partial discharge signal and the third partial discharge signal.

[0091] The host computer analyzes and processes the first partial discharge signal, the second partial discharge signal, and the third partial discharge signal that are periodically uploaded by the host and the slave multiple times, calculates the arrival time of the partial discharge signal collected by the host and the arrival time difference of the partial discharge signal collected by the slave, and calculates the precise location of the partial discharge point in the cable.

[0092] The formula for accurately locating the partial discharge point in a cable is as follows: ; in, The distance from the host machine to the location of the partial discharge point in the cable; The arrival time of the first partial discharge signal acquired by the host computer; This represents the arrival time of the third partial discharge signal acquired by the slave device; Indicates the time of the time; This indicates a fixed time delay.

[0093] This application provides a cable partial discharge detection and location system based on synchronous pulses and time compensation. For any detection and location device: the host computer sends a synchronous compensation command to the main unit. The intelligent synchronous compensation module and the synchronous pulse unit of the main unit excite a first synchronous compensation pulse signal on the shielding grounding wire of the cable within the target area. Simultaneously, the intelligent synchronous compensation module of the main unit converts and processes this first synchronous compensation pulse signal for identification by the detection and location synchronous acquisition module of the main unit. After detecting the first synchronous compensation pulse signal, the adjacent slave device responds with a pulse after a fixed conversion delay. The intelligent synchronous compensation module of the main unit converts and processes the returned pulse signal again and sends it to the detection and location synchronous acquisition module of the main unit. The detection and location synchronous acquisition module of the main unit records the round-trip time of the compensation pulse. The host computer calculates the compensation time required for the slave device delay based on the round-trip time. When locating the location of partial discharge on the cable line, the main unit and the slave device synchronously acquire the synchronous pulse signal on the shielding grounding wire of the cable, calculate the time difference after compensation, and finally achieve accurate location of the discharge point. This application achieves delay compensation through synchronous pulse round-trip measurement of the cable shield grounding wire, which effectively improves the accuracy and reliability of partial discharge location in cables and is applicable to power cable condition monitoring and fault early warning systems.

[0094] Existing technologies often employ partial discharge detection channels for pulse delay identification and calculation in synchronizing pulse time calculation. This requires identifying and calculating numerous time parameters, and in partial discharge localization, it is necessary to simultaneously detect the time difference between the synchronizing pulse waveform and the partial discharge waveform. This places extremely high demands on the signal-to-noise ratio of the detection channel, requiring the differentiation of both the partial discharge signal and the synchronizing pulse signal, making it challenging to use in engineering applications. This application innovatively utilizes a synchronizing pulse signal excited on the shielding grounding wire of a high-voltage power cable line. Through pulse response and pulse feedback, the time difference before and after the pulse is calculated to obtain the compensation time. Furthermore, the compensation time calculation does not rely on the partial discharge detection channel of the detection and positioning synchronization acquisition module sampling the pulse waveform. Instead, it uses an intelligent synchronization compensation module to convert the pulse signal, and the detection and positioning synchronization acquisition module identifies the converted signal for time calculation. This achieves accurate, reliable, and stable synchronous acquisition at both ends of the distributed partial discharge detection device for cables at different detection environments and distances, improving positioning accuracy.

[0095] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0096] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A cable partial discharge detection and location system based on synchronous pulse and time compensation, characterized in that, The system includes: The host computer and multiple detection and positioning devices; The host computer is used to mark adjacent detection and positioning devices within the target area and to determine the master and slave devices; The host is used for: According to the synchronization compensation command output by the host computer, a first synchronization compensation pulse signal is generated on the shielding grounding wire of the cable in the target area, and a second synchronization compensation pulse signal generated by the slave device according to the first synchronization compensation pulse signal is received. The timing time is determined based on the first synchronization compensation pulse signal and the second synchronization compensation pulse signal, and then sent to the host computer. The host computer is also used to determine the compensation time based on the timing time, and output periodic synchronous acquisition and positioning commands after the compensation time is determined; The host computer is also used to excite a first synchronous acquisition pulse signal on the shielding grounding wire of the cable in the target area after receiving a periodic synchronous acquisition and positioning command output by the host computer, and to acquire a first partial discharge signal on the shielding grounding wire of the cable in the target area acquired under the first synchronous acquisition pulse signal. The slave device is used for: Based on the first synchronous acquisition pulse signal and the compensation time, a compensation interval and a second synchronous acquisition pulse signal are generated, and a second partial discharge signal on the shield grounding wire of the cable in the target area acquired under the compensation interval and a third partial discharge signal on the shield grounding wire of the cable in the target area acquired under the second synchronous acquisition pulse signal are obtained; the next moment after the last moment corresponding to the second partial discharge signal is the first moment corresponding to the third partial discharge signal. The host computer is also used to determine the location of partial discharge of the cable within the target area based on the first partial discharge signal, the second partial discharge signal and the third partial discharge signal.

2. The cable partial discharge detection and positioning system based on synchronous pulse and time compensation according to claim 1, characterized in that, Regarding target area determination, the host computer is used for: The target area is determined based on the fourth partial discharge signal sent by each detection and positioning device; the target area is the location range of the partial discharge point of the cable. The fourth partial discharge signal is a partial discharge signal collected by each detection and positioning device according to the signal acquisition command sent by the host computer.

3. The cable partial discharge detection and positioning system based on synchronous pulse and time compensation according to claim 1, characterized in that, Each of the aforementioned detection and positioning devices includes a detection and positioning synchronous acquisition module, an intelligent synchronous compensation module, a synchronous pulse unit, and a partial discharge coupling unit; The detection, positioning, and synchronous acquisition module is connected to the intelligent synchronous compensation module, the partial discharge coupling unit, and the host computer, respectively. The intelligent synchronization compensation module is connected to the synchronization pulse unit; The synchronization pulse unit and the partial discharge coupling unit are used to connect to the shielding ground wire of the cable.

4. The cable partial discharge detection and positioning system based on synchronous pulse and time compensation according to claim 3, characterized in that, The host computer is used to control the partial discharge coupling unit of the host computer to continuously collect partial discharge signals on the shielding ground wire of the cable in the target area after receiving the periodic synchronous acquisition and positioning command output by the host computer. The slave device is used to continuously collect partial discharge signals on the shielded grounding wire of the cable within the target area after receiving the periodic synchronous acquisition and positioning command output by the host computer, and in conjunction with time compensation, control the partial discharge coupling unit of the slave device.

5. The cable partial discharge detection and positioning system based on synchronous pulse and time compensation according to claim 1 or 3, characterized in that, The detection, positioning, and synchronous acquisition module of the host computer is used to control the intelligent synchronous compensation module of the host computer to generate a first synchronous compensation signal according to the synchronous compensation instruction from the host computer. The master's synchronization pulse unit is used to generate a first synchronization compensation pulse signal on the shielded grounding wire of the cable in the target area according to the first synchronization compensation signal, and to receive a second synchronization compensation pulse signal generated by the slave according to the first synchronization compensation pulse signal.

6. The cable partial discharge detection and positioning system based on synchronous pulse and time compensation according to claim 4, characterized in that, The synchronization pulse unit of the host is also used to send the first synchronization compensation pulse signal to the intelligent synchronization compensation module of the host. The intelligent synchronization compensation module of the host is used to process the first synchronization compensation pulse signal into a timing signal and send the timing signal to the detection and positioning synchronization acquisition module of the host. The host's detection, positioning, and synchronization acquisition module is used to start timing when it receives the timing signal; The synchronization pulse unit of the host is also used to receive the second synchronization compensation pulse signal and send the second synchronization compensation pulse signal to the intelligent synchronization compensation module of the host. The intelligent synchronization compensation module of the host is used to process the second synchronization compensation pulse signal into a stop timing signal and send the stop timing signal to the detection and positioning synchronization acquisition module of the host. The host's detection, positioning, and synchronization acquisition module is used to stop timing and determine the timing time when it receives the stop timing signal.

7. The cable partial discharge detection and positioning system based on synchronous pulse and time compensation according to claim 1 or 3, characterized in that, The detection, positioning, and synchronous acquisition module of the host computer is used to control the intelligent synchronous compensation module of the host computer to generate a first synchronous acquisition signal when it receives a periodic synchronous acquisition and positioning command output by the host computer. The synchronization pulse unit of the host is used to excite the first synchronization acquisition pulse signal on the shield grounding wire of the cable in the target area according to the first synchronization acquisition signal, and to send the first synchronization acquisition pulse signal to the intelligent synchronization compensation module of the host. The intelligent synchronization compensation module of the host is used to process the first synchronization acquisition pulse signal into a first acquisition signal and send the first acquisition signal to the detection and positioning synchronization acquisition module of the host. The detection and positioning synchronous acquisition module of the host is used to acquire the partial discharge signal acquired by the partial discharge coupling unit of the host, and to filter the acquired partial discharge signal based on the first acquisition signal to obtain the first partial discharge signal on the shield grounding wire of the cable in the target area acquired under the first acquisition signal.

8. The cable partial discharge detection and positioning system based on synchronous pulse and time compensation according to claim 1 or 3, characterized in that, The slave device's synchronization pulse unit is used to receive the first synchronization compensation pulse signal and send the first synchronization compensation pulse signal to the slave device's intelligent synchronization compensation module. The slave device's intelligent synchronization compensation module is used to convert the first synchronization compensation pulse signal into a second synchronization compensation signal through a fixed time delay. The slave device's synchronization pulse unit is used to generate a second synchronization compensation pulse signal on the shielded grounding wire of the cable within the target area according to the second synchronization compensation signal.

9. The cable partial discharge detection and positioning system based on synchronous pulse and time compensation according to claim 3, characterized in that, The slave device's synchronization pulse unit is used to send the received first synchronization acquisition pulse signal to the slave device's intelligent synchronization compensation module; The slave device's intelligent synchronization compensation module is used to process the first synchronization acquisition pulse signal into a second acquisition signal, and send the second acquisition signal to the slave device's detection and positioning synchronization acquisition module; The slave device's detection, positioning, and synchronous acquisition module is used to generate a compensation interval based on the second acquisition signal and the compensation time sent by the host computer. The slave device's detection and positioning synchronous acquisition module is also used to acquire the partial discharge signal acquired by the slave device's partial discharge coupling unit, and to filter the acquired partial discharge signal based on the second acquisition signal and the compensation interval to obtain the second partial discharge signal on the shield grounding wire of the cable in the target area acquired under the compensation interval and the third partial discharge signal on the shield grounding wire of the cable in the target area acquired under the second acquisition signal.

10. A method for detecting and locating partial discharge in cables based on synchronization pulses and time compensation, characterized in that, The method includes: The host computer marks adjacent detection and positioning devices within the target area to identify the master and slave devices; The host computer, according to the synchronization compensation command output by the host computer, excites a first synchronization compensation pulse signal on the shield grounding wire of the cable in the target area, and receives a second synchronization compensation pulse signal excited by the slave computer according to the first synchronization compensation pulse signal. The timing time is determined based on the first synchronization compensation pulse signal and the second synchronization compensation pulse signal, and then sent to the host computer. The host computer determines the compensation time based on the timing time, and outputs a periodic synchronous acquisition and positioning command after the compensation time is determined; When the host computer receives the periodic synchronous acquisition and positioning command output by the host computer, it excites a first synchronous acquisition pulse signal on the shielding grounding wire of the cable in the target area, and acquires the first partial discharge signal on the shielding grounding wire of the cable in the target area acquired under the first synchronous acquisition pulse signal. The slave device generates a compensation interval and a second synchronous acquisition pulse signal based on the first synchronous acquisition pulse signal and the compensation time, and acquires a second partial discharge signal on the shield grounding wire of the cable in the target area acquired under the compensation interval and a third partial discharge signal on the shield grounding wire of the cable in the target area acquired under the second synchronous acquisition pulse signal; the next moment after the last moment corresponding to the second partial discharge signal is the first moment corresponding to the third partial discharge signal. The host computer determines the location of partial discharge in the cable within the target area based on the first partial discharge signal, the second partial discharge signal, and the third partial discharge signal.

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