Line loss fault point positioning method and system for electric power engineering construction

Abstract

The invention relates to the technical field of power grid operation and maintenance, in particular to a line loss fault point positioning method and system for electric power engineering construction, and the method comprises the following steps: releasing a fault detection device, enabling the fault detection device to advance on a cable along a determined direction, and enabling the fault detection device to be provided with a plurality of ultrasonic receivers; the fault detection device presses the cable, the to-be-detected cable is bent to form a bent part, and a fault point in the bent part is discharged; obtaining a response signal generation moment of the receiver for partial discharge of the cable; and calculating the difference value of the generation moments of the response signals of the two receivers. According to the invention, the interference of a background electric field and a magnetic field is eliminated by pressing the cable in real time to force the cable to discharge the line loss fault point with the discharge trend and adopting the ultrasonic wave as the characteristic signal to obtain the time difference of arrival, the power-off operation is not needed, the line loss fault point caused by partial discharge can be accurately positioned, and the positioning accuracy is improved. And the troubleshooting difficulty and the missed detection condition are reduced.

Description

Technical Field

[0001] The present application relates to the technical field of power grid operation and maintenance, and in particular to a method and system for locating line loss fault points in power engineering construction. Background Art

[0002] There are many reasons for line loss failure of cables in power transmission lines in power engineering. Line loss failure caused by partial discharge due to internal defects in the cable insulation layer is more common.

[0003] In the prior art, the method for troubleshooting and detecting line loss faults caused by partial discharge of cables generally involves inputting a test current into the cable to be tested after a power outage to achieve cable fault troubleshooting and detection. This method needs to be performed after the power outage of the transmission line, which will lead to a stagnation in the progress of the operation. In addition, this method is suitable for segmented inspection of cables. Point-to-point inspection of cable line loss faults is difficult and often leads to missed detections.

[0004] Therefore, there is a need for a method that can accurately locate the line loss fault point caused by partial discharge of the cable without shutting down the transmission line. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present application provides a method and system for locating line loss fault points in power engineering construction, which eliminates interference from background electric and magnetic fields by real-time compression of the cable to force the line loss fault points with a discharge tendency, and uses ultrasound as a characteristic signal to obtain the arrival time difference, eliminating the need for power outages and accurately locating line loss fault points caused by local discharge, reducing the difficulty of troubleshooting and the possibility of missed detections.

[0006] The above application objectives of this application are achieved through the following technical solutions: A method for locating line loss fault points in power engineering construction comprises the following steps: releasing the fault detection device to make it move along a determined direction on the cable, wherein the fault detection device has a plurality of ultrasonic receivers; The fault detection device presses the cable, and the cable to be tested is bent to form a bent portion, so that the fault point in the bent portion discharges; Obtaining the time when the receiver generates a response signal to the partial discharge of the cable; Calculate the difference between the times when two receiver response signals are generated; The location of the partial discharge on the cable is calculated based on the time difference of the response signals between the two receivers.

[0007] Optionally, calculating the location of the partial discharge of the cable includes: Calculate a possible location set of the partial discharge of the cable based on the acquired time difference of the response signal between the two receivers; Obtaining a current travel route set of the fault detection device; Calculating the intersection of the possible position set and the travel route set; The location of the partial discharge of the cable is determined according to the intersection of the possible location set and the travel route set.

[0008] Optionally, calculating the location of the partial discharge of the cable includes: At least two groups of differences in the generation time are calculated, and the receivers corresponding to the differences in the two groups of generation time are not completely the same; The possible position set of the cable partial discharge is calculated according to the difference of each group of generation time, and each group of generation time difference corresponds to a possible position set; Calculating the intersection of a plurality of the possible position sets; The location of the partial discharge of the cable is determined according to the intersection of a plurality of the possible location sets.

[0009] Optionally, calculating the position of the partial discharge of the cable further includes: Obtaining the position of the release point of the fault detection device and the current travel route of the fault detection device; calculating the current position of the fault detection device on the cable; Obtaining the relative position of the partial discharge point of the cable with respect to the fault detection device; According to the current position of the fault detection device and the relative position of the partial discharge point of the cable, the relative position of the partial discharge point of the cable with respect to the release point of the fault detection device is calculated.

[0010] Optionally, calculating the position of the partial discharge of the cable further includes: Obtaining the time when the response signal of the receiver that first receives the ultrasonic signal is generated, and the travel speed of the fault detection device at that time; Obtain the time difference between the time when the receiver that first receives the ultrasonic signal and the time when other receivers generate response signals; The time difference is corrected according to the travel speed of the fault detection device.

[0011] The embodiment of the present application also provides a line loss fault point location system for power engineering construction, including a bearing and a processing unit, the bearing is provided with a driving unit for driving the bearing to move on the cable, and an ultrasonic receiving unit for detecting partial discharge of the cable, and the ultrasonic receiving units have at least two; The processing unit is signal-connected to the driving unit and the plurality of ultrasonic receiving units; One end of the bearing member is provided with a bending head for pressing the cable to bend the cable, at least one ultrasonic receiving unit is located outside the bottom of the bending head, and at least one ultrasonic receiving unit is located outside the top of the bending head.

[0012] Optionally, a deformation groove that can accommodate the cable and provide deformation space for the cable is opened at the bottom of the bending head. The inner side of the deformation groove is the fitting surface of the cable. The angle between the central axis of the deformation groove and the central axis of the carrier is an obtuse angle. The opening of the deformation groove away from one end of the carrier is located above the carrier.

[0013] Optionally, a hanging piece is provided at the bottom of the bending head.

[0014] Optionally, the driving unit includes a driving motor and a driving wheel connected to a rotating shaft of the driving motor and used for contacting the cable, and the driving motor is signal-connected to the processing unit.

[0015] In summary, this application has the following beneficial technical effects: The present application compresses the cable in real time to force the line loss fault point with a discharge tendency to discharge, and uses ultrasound as a characteristic signal to obtain the arrival time difference, thereby eliminating the interference of background electric and magnetic fields, eliminating the need for power outages, and being able to accurately locate the line loss fault point caused by local discharge, reducing the difficulty of troubleshooting and the possibility of missed detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the detection arrangement of the present application; Figure 2 It is a schematic diagram of partial discharge at the bending portion of the cable to be tested in this application; Figure 3 It is a schematic diagram of locating the partial discharge line loss fault point of the cable to be tested in this application; Figure 4 This is a schematic diagram of locating the partial discharge line loss fault point based on the travel route of this application; Figure 5 This is a schematic diagram of locating the partial discharge line loss fault point by using multiple groups of receivers in this application; Figure 6 It is a schematic diagram of the layout of the positioning system of the present application; Figure 7 It is a schematic diagram of the positioning system of the present application compressing the cable to produce a bend.

[0017] Reference numerals: 10, bearing member; 11, bending head; 12, deformation groove; 13, hanging member; 20. Processing unit; 30. driving unit; 31. driving motor; 32. driving wheel; 40. Ultrasonic receiving unit. DETAILED DESCRIPTION

[0018] The present application is further described in detail below in conjunction with the accompanying drawings.

[0019] In order to more clearly understand the technical solution presented in the embodiments of the present application, a brief introduction is first given to the partial discharge of transmission line cables during power engineering construction.

[0020] When the cable insulation layer is manufactured, it may have inclusions and cavities inside. The defective parts such as inclusions and cavities in the cable insulation layer can be regarded as an equivalent capacitor. When current passes through the cable, the charge is accumulated at both ends of the equivalent capacitor. When the accumulated charge on the capacitor screens at both ends of the equivalent capacitor exceeds the limit, or the voltage between the capacitor screens at both ends of the equivalent capacitor exceeds the limit, the equivalent capacitor will break down, and the equivalent capacitor temporarily becomes a pathway, which manifests as partial discharge line loss of the cable, and ultrasonic waves will be released at this time.

[0021] When the equivalent capacitor is discharged, the voltage between the capacitor screens at both ends of the equivalent capacitor returns to the extinguishing voltage. As the current continues to flow, the charge continues to accumulate on the capacitor screens at both ends of the equivalent capacitor until the voltage between the capacitor screens at both ends of the equivalent capacitor exceeds the initial discharge voltage, and the equivalent capacitor continues to discharge.

[0022] In order to accurately locate the line loss fault point caused by partial discharge of defective equivalent resistance in the cable without power outage, the embodiment of the present application provides a line loss fault point locating method for power engineering construction, including the following steps: S101, placing a fault detection device on the cable and moving it forward; S102, the fault detection device presses the cable to be tested to bend the cable to be tested, and the cable to be tested is bent to form a bent portion, so that the fault point in the bent portion discharges; S103, obtaining the initial generation time of the response signal of the ultrasonic receiver on the fault detection device to the partial discharge of the cable; S104, calculating the difference between the initial generation times of the two receiver response signals; S105 : Calculate the location of the partial discharge of the cable according to the difference in initial response time of the response signals of the two receivers.

[0023] In combination with specific usage scenarios, the technical solution displayed in the embodiment of the present application is further introduced by taking the situation where the cable is partially discharged due to the presence of cavities in the cable insulation layer as an example. Of course, in addition to being effective for the situation where the cable is partially discharged due to the presence of cavities in the cable insulation layer, the embodiment of the present application is still effective for detecting and locating partial discharge phenomena caused by other defects in the cable insulation layer.

[0024] First, step S101 is executed to release the fault detection device. The fault detection device has a plurality of ultrasonic receivers for receiving ultrasonic signals, which can be used to detect ultrasonic signals generated by partial discharge of the cable to be tested. The arrangement of the ultrasonic receivers can refer to Figure 1 , the released fault detection device travels on the cable in a determined direction; In step S102, refer to Figure 2 The fault detection device moves on the cable to be tested. Under the influence of the fault detection device's own weight, the cable is compressed and deformed. The cable near the end of the fault detection device is deformed most violently. The cable at the aforementioned position is bent to form a bending portion of the cable. According to the description of the above-mentioned equivalent capacitor, it can be found that the occurrence of the equivalent capacitor breakdown effect depends on the accumulation of the charge on the capacitor screen at both ends of the equivalent capacitor. When the charge on the capacitor screen at both ends of the equivalent capacitor does not exceed the limit, the equivalent capacitor will not break down. In the prior art, when the instrument used to detect partial discharge passes through an area where no partial discharge has occurred temporarily but there is a tendency for partial discharge, the area will be skipped because there is no specific identifiable feature for detecting partial discharge. After the instrument used to detect partial discharge leaves the aforementioned area and the equivalent capacitor breaks down, the instrument cannot detect the partial discharge signal. This is also the reason why point-to-point troubleshooting of cable line loss faults in the prior art is difficult and there are many missed detections. In the embodiment of the present application, the fault detection device compresses the cable to be tested so that part of the cable to be tested is bent and deformed into a bent portion, and the shape of the internal cavity of the insulating layer of the bent portion of the cable will also change. When the cavity is located on the side of the insulating layer close to the fault detection device, the part of the cavity close to the fault detection device is compressed, and the distance between the two internal end faces is reduced. The gap of the part of the cavity away from the fault detection device expands, and the distance between the two internal end faces increases; when the cavity is located on the side of the insulating layer away from the fault detection device, the gap of the part of the cavity away from the fault detection device expands sharply, and the increment of the expansion is greater than that of the part of the cavity close to the fault detection device; no matter which of the above two situations the cavity is in, it will cause the continuous reduction of the area facing the capacitor screen at both ends of the equivalent capacitor. When the voltage is mounted at both ends of the cable, the amount of charge already attached to both ends of the equivalent capacitor increases, so that the breakdown voltage limit value of the equivalent capacitor is significantly reduced due to the bending of the cable, thereby forcing the equivalent capacitor to undergo breakdown discharge; Of course, the above principle can also be understood as follows: due to the bending of the cable, the amount of charge and voltage required for accumulating the breakdown limit at both ends of the cavity equivalent capacitor of the cable bending portion are significantly reduced, thereby significantly reducing the cycle time of charging and discharging of the equivalent capacitor. This enables the fault detection device in the embodiment of the present application to always detect the discharge of most defects in the cable when traveling, thereby reducing the probability of missed detection and reducing the difficulty of troubleshooting the fault point; Then, step S103 is performed. After the equivalent capacitor is discharged, the receiver on the fault detection device can receive the ultrasonic excitation signal. At this time, the initial time when the response signal of each receiver is generated is obtained and recorded, that is, the initial generation time of the response signal of each receiver is obtained and recorded. In the embodiment of the present application, ultrasonic waves are used as characteristic signals for detection and positioning, instead of using pulses or magnetic field signals emitted when the cable line loss fault is used as characteristic signals, which eliminates the interference of background electric and magnetic fields in actual use scenarios; In step S104, the time difference between the initial generation times of the response signals of two receivers is calculated; Finally, step S105 is executed, referring to Figure 3 , according to the difference in the initial response time of the response signal between the two receivers, as well as the distribution status and location of the current cable to be tested, the location of the partial discharge of the cable is calculated to achieve accurate positioning of the line loss fault point caused by partial discharge of the cable; In addition to the positioning method described in step S105 above that relies on the current position and state of the cable, in the embodiment of the present application, by calculating the time difference between the initial generation times of the response signals of two receivers, the cable line loss fault point is located. There are at least two achievable forms. For the convenience of description and explanation, the specific usage scenario is reduced in dimension by projection. By way of example, the actual usage scenario can also be used to locate the line loss fault point by dimensionality reduction. Of course, if it is necessary to locate the line loss fault point of the cable in three dimensions, the method shown in the embodiment of the present application is also applicable. The only difference is the dimension of the identifiable feature vector: Reference Figure 4 , one possible way to do this includes the following steps: Step S201: Calculate a possible position set of the cable partial discharge location according to the acquired time difference of the response signal between the two receivers. In the scenario of dimensionality reduction as an example, specifically, the elements in the possible position set are a set of position coordinates where the partial discharge characteristic signal may exist. The aforementioned position coordinates are a two-dimensional vector. It should be understood that the position coordinates where the partial discharge characteristic signal may exist in the possible position set are not necessarily located on the cable. The position coordinates where the partial discharge characteristic signal may exist are for the receiver. In the scenario of dimensionality reduction as an example, since the distance and position relationship between the receivers on the fault detection device are fixed, the ultrasonic signal propagates in the medium and is received by each receiver. For a certain ultrasonic signal, the time difference between two receivers receiving the ultrasonic signal can be obtained by calculation. Then, for a receiver group consisting of two receivers, the possible position set is expressed by a graph, which is actually a hyperbola between the receivers in the group. The two foci of the hyperbola are the positions of the two receivers in the group, and each point on the hyperbola is the position coordinate where the local discharge characteristic signal may exist. Step S202: obtaining the current travel route set of the fault detection device. During the specific travel process, the travel path of the fault detection device is a curve. The aforementioned current travel route set should be the path line of the fault detection device from the initial release position to the current position. Each point on the aforementioned path line is an element in the current travel route set. The path line described in the current travel route set of the fault detection device can be based on the central axis of the cable to be tested, or can be based on the part of the fault detection device that is actually in contact with the cable. In fact, when obtaining the current travel route set of the fault detection device, the current position coordinate band of the fault detection device can be periodically collected and then fitted; Step S203: calculating the intersection of the possible position set and the travel route set. Of course, it can also be understood as calculating the elements of the possible position set that meet the constraint conditions of the travel route set. Step S204: determining the location of the cable partial discharge according to the intersection of the possible location set and the travel route set, where the location of the cable partial discharge is also the intersection element of the possible location set and the travel route set.

[0025] This detection and positioning method can locate the line loss fault point caused by partial discharge of the cable to be tested through only two calculations, and the positioning is accurate to the exact position of the cable, with fast calculation speed and high efficiency.

[0026] Reference Figure 5 , another possible implementation method includes the following steps: Step S301: the number of receivers capable of receiving ultrasonic waves on the fault detection device is at least three, and the three receivers can form three receiver groups. The number of receivers in each receiver group is two, and the receiver numbers in the several receiver groups are not completely the same. At least two receiver groups work simultaneously, and when collecting the difference in the time when the initial response signal is generated, at least two groups are collected, that is, the difference in the time when the initial response signal is generated is calculated for at least two groups, and the receivers corresponding to the difference in the time when the two groups are generated are not completely the same; Step S302: Calculate the possible position set of the cable partial discharge according to the difference of each group of generation time. Each group of generation time difference corresponds to a possible position set. In the case of a graphic as a concrete representation, taking the possible position set obtained by two groups of receivers as an example, each group of receivers has one of the hyperbolas with the two receivers as foci, and each point on the hyperbola is an element of the aforementioned possible position set, and the position coordinates of the element are represented by a two-dimensional vector; Step S303: Calculate the intersection of the multiple possible position sets. In the case of a graphic representation, it can be found that the two groups of receivers can form two intersecting hyperbolas, and the foci of the two hyperbolas with different focal positions are the intersection of the possible position sets. Step S304: determining the position of the partial discharge of the cable according to the intersection of the plurality of possible position sets, that is, the focus of two hyperbolas with different focus positions.

[0027] This detection and positioning method calculates the possible position sets of two groups of receivers. It is independent of the travel path of the fault detection device and can locate the fault point to a specific location on the cable with high positioning accuracy.

[0028] In general, the embodiments of the present application force the line loss fault point with a discharge tendency to discharge by compressing the cable in real time, and use ultrasound as a characteristic signal to obtain the arrival time difference, thereby eliminating the interference of the background electric and magnetic fields, eliminating the need for power outages, and being able to accurately locate the line loss fault point caused by local discharge, reducing the difficulty of troubleshooting and the possibility of missed detection.

[0029] As a feasible specific implementation method of the embodiment of the present application, calculating the position of the partial discharge of the cable also includes: Step S401: obtaining the position of the release point of the fault detection device and the current travel route of the fault detection device. The position of the release point of the fault detection device is also the starting point of the total travel route of the fault detection device. The current travel route of the fault detection device can be formed by periodically collecting coordinate point information of the current position of the fault detection device when the fault detection device is moving, and then fitting the aforementioned several collected coordinate points into a curve, thereby forming the current travel route of the fault detection device; Step S402: By using the starting point and the current travel route obtained in step S401, it is easy to calculate the position of the fault detection device relative to the starting point; Step S403: obtaining the relative position of the cable partial discharge location relative to the fault detection device; Step S404: Calculate the relative position of the partial discharge point of the cable relative to the release point of the fault detection device according to the current position of the fault detection device and the relative position of the partial discharge point of the cable.

[0030] Simply put, in the embodiment of the present application, by obtaining the starting point position information of the fault detection device and the current route of the fault detection device, the cable fault point position information relative to the current position of the fault detection device is converted into the relatively fixed initial release point position information, so that after the entire cable is inspected, the operator can clearly and easily find the exact location of the cable fault point.

[0031] It can be understood that the fault detection device moves on the cable to be tested. Under ideal conditions, the fault detection device and the cable to be tested do not slip. Then, the total travel route length of the fault detection device should be equal to the length of the detected area of ​​the cable to be tested. In other words, when the current position point of the fault detection device is taken as the determination point, the current travel route of the fault detection device is intercepted with the determination point and the initial release point as endpoints. Then the length of the curve between the two points is determined. After the fault detection device is removed from the cable to be tested, the operator can determine the current position point of the fault detection device on the cable to be tested by relying on the aforementioned intercepted route length, even if the fault detection device has been removed; Of course, in actual usage scenarios, the fault detection device will inevitably slip between the cable to be tested. In the embodiment of the present application, the current travel route of the fault detection device is fitted by periodically collecting the current position points of the fault detection device. Therefore, after the fault detection device is removed, the operator determines that the position of the fault detection device on the cable to be tested before being removed still meets the requirements.

[0032] As a feasible specific implementation method of the embodiment of the present application, calculating the position of the partial discharge of the cable also includes: Step S501: When a plurality of receivers are unevenly distributed and a partial discharge occurs at a bending portion of the cable to be tested, the plurality of receivers receive ultrasonic signals at different times. Therefore, the times at which the plurality of receivers generate response signals will also differ. At this time, the time at which the response signal of the receiver that first receives the ultrasonic signal is generated, and the travel speed of the fault detection device at that time is obtained; Step S502: Obtain the time difference between the time when the receiver that first receives the ultrasonic signal and the time when other receivers generate response signals; Step S503: Correcting the time difference according to the travel speed of the fault detection device.

[0033] It can be understood that when the ultrasonic excitation signal propagates at a certain speed in the air medium, the fault detection device is also moving. The time difference in the response signals between the two ultrasonic receivers is the result of the combined effect of the propagation of the ultrasonic excitation signal and the movement of the fault detection device. That is, the movement of the fault detection device will cause the time difference between the two receivers to be higher. By correcting the time difference, the positioning accuracy of the cable partial discharge line loss fault point can be effectively improved.

[0034] In some possible implementations of the embodiments of the present application, the offset displacement of the fault detection device within the aforementioned time difference can be calculated first, and then the time required for the ultrasonic signal to propagate the offset displacement length can be calculated. Finally, the time difference can be corrected by subtracting the aforementioned required time from the time difference.

[0035] The embodiment of the present application also provides a line loss fault point locating system for electric power engineering construction, which serves as the hardware support and implementation platform of the above-mentioned line loss fault point locating method for electric power engineering construction, and corresponds to the fault detection device in the above-mentioned method as a whole, with reference to Figure 6 and Figure 7 Specifically, it includes a processing unit 20 for processing data and calculating, and a carrier 10 as a mounting base for an accessory, the carrier 10 is provided with a driving unit 30 for driving the carrier 10 to move on the cable, and an ultrasonic receiving unit 40 for detecting partial discharge of the cable, and the ultrasonic receiving unit 40 has at least two; The processing unit 20 is signal-connected to the driving unit 30 and the plurality of ultrasonic receiving units 40; One end of the carrier 10 has a bending head 11 for pressing the cable to bend the cable. The distances between the plurality of ultrasonic receiving units 40 and the bending head 11 are different. At least one ultrasonic receiving unit 40 is located outside the bottom of the bending head 11, and at least one ultrasonic receiving unit 40 is located outside the top of the bending head 11.

[0036] When in use, the carrier 10 moves on the cable to be tested. Due to the deadweight of the carrier 10 and the accessories installed on the carrier 10, the cable to be tested is bent at the bending head 11, so that the equivalent capacitor inside it is forced to discharge. The ultrasonic signal released by the partial discharge is recognized by the ultrasonic receiving unit 40 and generates an excitation signal. The processing unit 20 can control the operation of each component, accept the working parameters of each component, and calculate the received parameters.

[0037] In the embodiment of the present application, a deformation groove 12 that can accommodate the cable and provide a deformation space for the cable is opened at the bottom of the bending head 11. The inner side of the deformation groove 12 is the fitting surface of the cable. The angle between the central axis of the deformation groove 12 and the central axis of the carrier 10 is obtuse. The opening of the deformation groove 12 away from one end of the carrier 10 is located above the carrier 10. When the carrier 10 moves above the cable to be tested, the part of the cable to be tested located at the bending head 11 is bent. Of course, a suspension member 13 may also be provided at the bottom of the bending head 11 to make the center of gravity of the fault detection device close to the bottom of the bending head 11.

[0038] The driving unit 30 serves as an actuator for driving the fault detection device to move on the cable to be tested. Specifically, it may include a driving motor 31 and a driving wheel 32 connected to the rotating shaft of the driving motor 31 and used to contact the cable. The driving motor 31 is connected to the processing unit 20 by signal. After the processing unit 20 sends a start command to the driving motor 31, the driving motor 31 drives the driving wheel 32 to rotate, and the driving wheel 32 is frictionally connected to the outer side of the insulation layer of the cable to be tested, thereby driving the fault detection device to move on the cable to be tested.

[0039] The embodiments of this specific implementation method are all preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. Therefore, all equivalent changes made based on the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A method for locating line loss fault points in power engineering construction, characterized in that: include: releasing the fault detection device to make it move along a determined direction on the cable, wherein the fault detection device has a plurality of ultrasonic receivers; The fault detection device presses the cable, and the cable to be tested is bent to form a bent portion, so that the fault point in the bent portion discharges; Obtaining the time when the receiver generates a response signal to the partial discharge of the cable; Calculate the difference between the times when two receiver response signals are generated; The location of the partial discharge on the cable is calculated based on the time difference of the response signals between the two receivers.

2. A line loss fault point locating method for electric power engineering construction according to claim 1, characterized in that: The calculation of the location of the partial discharge of the cable includes: Calculate a possible location set of the partial discharge of the cable based on the acquired time difference of the response signal between the two receivers; Obtaining a current travel route set of the fault detection device; Calculating the intersection of the possible position set and the travel route set; The location of the partial discharge of the cable is determined according to the intersection of the possible location set and the travel route set.

3. A method for locating line loss fault points in power engineering construction according to claim 1, characterized in that: The calculation of the location of the partial discharge of the cable includes: At least two groups of differences in the generation time are calculated, and the receivers corresponding to the differences in the two groups of generation time are not completely the same; The possible position set of the cable partial discharge is calculated according to the difference of each group of generation time, and each group of generation time difference corresponds to a possible position set; Calculating the intersection of a plurality of the possible position sets; The location of the partial discharge of the cable is determined according to the intersection of a plurality of the possible location sets.

4. A method for locating line loss fault points in power engineering construction according to one of claims 2 or 3, characterized in that: The calculation of the position of the partial discharge of the cable also includes: Obtaining the position of the release point of the fault detection device and the current travel route of the fault detection device; calculating the current position of the fault detection device on the cable; Obtaining the relative position of the partial discharge point of the cable with respect to the fault detection device; According to the current position of the fault detection device and the relative position of the partial discharge point of the cable, the relative position of the partial discharge point of the cable with respect to the release point of the fault detection device is calculated.

5. A line loss fault point locating method for electric power engineering construction according to claim 4, characterized in that: The calculation of the position of the partial discharge of the cable also includes: Obtaining the time when the response signal of the receiver that first receives the ultrasonic signal is generated, and the travel speed of the fault detection device at that time; Obtain the time difference between the time when the receiver that first receives the ultrasonic signal and the time when other receivers generate response signals; The time difference is corrected according to the travel speed of the fault detection device.

6. A line loss fault point location system for power engineering construction, characterized in that: It comprises a bearing member and a processing unit, wherein the bearing member is provided with a driving unit for driving the bearing member to move on the cable and an ultrasonic receiving unit for detecting partial discharge of the cable, and the ultrasonic receiving units have at least two; The processing unit is signal-connected to the driving unit and the plurality of ultrasonic receiving units; One end of the bearing member is provided with a bending head for pressing the cable to bend the cable, at least one ultrasonic receiving unit is located outside the bottom of the bending head, and at least one ultrasonic receiving unit is located outside the top of the bending head.

7. A line loss fault point location system for electric power engineering construction according to claim 6, characterized in that: A deformation groove is provided at the bottom of the bending head to accommodate the cable and provide deformation space for the cable. The inner side of the deformation groove is the fitting surface of the cable. The angle between the central axis of the deformation groove and the central axis of the carrier is an obtuse angle. The opening of the deformation groove away from one end of the carrier is located above the carrier.

8. A line loss fault point location system for electric power engineering construction according to claim 6, characterized in that: A hanging piece is arranged at the bottom of the bending head.

9. A line loss fault point location system for electric power engineering construction according to claim 6, characterized in that: The driving unit comprises a driving motor and a driving wheel connected to a rotating shaft of the driving motor and used for contacting the cable. The driving motor is connected to the processing unit signal.

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