A line loss fault point positioning method and system for power engineering construction

Abstract

The application relates to the technical field of power grid operation and maintenance, in particular to a line loss fault point positioning method and system for power engineering construction, which comprises the following steps: releasing a fault detection device, making the fault detection device travel on a cable in a determined direction, and the fault detection device being provided with a plurality of ultrasonic receivers; the fault detection device compresses the cable, the to-be-measured cable is bent to form a bending part, a fault point in the bending part is discharged; the response signal generation time of the receiver to the partial discharge of the cable is acquired; and the difference between the response signal generation time of two receivers is calculated. The application discharges the line loss fault point with a discharge tendency of the cable by real-time compression of the cable, adopts ultrasonic waves as characteristic signals to acquire the time difference, eliminates the interference of background electric field and magnetic field, does not need power-off operation, can accurately position the line loss fault point caused by partial discharge, and reduces the fault checking difficulty and the missed detection condition.

Description

TECHNICAL FIELD

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

[0002] In power engineering, there are various reasons for line loss faults of cables in power transmission lines, and line loss faults caused by partial discharge due to internal defects of cable insulation layers are more common.

[0003] In the prior art, for the exclusion and detection method of line loss faults caused by cable partial discharge, a detection current is input to the cable to be detected after power failure to realize the exclusion and detection of cable faults. This method needs to be performed after the power failure of the power transmission line, which will cause the stagnation of the operation progress, and this method is suitable for the segmented exclusion of the cable, and it is difficult to exclude the line loss fault point of the cable and there are more missed detections.

[0004] Therefore, a method is needed to accurately position the line loss fault point caused by cable partial discharge without power failure of the power transmission line. SUMMARY

[0005] In view of the deficiencies in the prior art, the present application provides a line loss fault point positioning method and system for power engineering construction, which discharges the line loss fault point of the cable with a discharge tendency by real-time compression of the cable, and uses ultrasonic waves as characteristic signals to obtain time difference, which excludes the interference of background electric field and magnetic field, does not need power failure operation, and can accurately position the line loss fault point caused by partial discharge, reducing the difficulty of fault exclusion and missed detection.

[0006] The above application purpose of the present application is realized by the following technical scheme:

[0007] A line loss fault point positioning method for power engineering construction, comprising the following steps:

[0008] Releasing the fault detection device, so that the fault detection device travels on the cable in a determined direction, and the fault detection device has a plurality of ultrasonic receivers thereon;

[0009] The fault detection device compresses the cable, the cable to be detected is bent to form a bent part, and the fault point in the bent part is discharged;

[0010] Obtaining the response signal generation time of the receiver to the cable partial discharge;

[0011] Calculating the difference between the response signal generation times of the two receivers;

[0012] According to the response signal time difference between the two receivers, the position of the cable partial discharge is calculated.

[0013] Optionally, the calculating the position of the cable partial discharge includes:

[0014] calculating a set of possible positions of the cable partial discharge according to the time difference of the response signals between the two receivers;

[0015] obtaining a set of current travel routes of the fault detection device;

[0016] calculating the intersection of the set of possible positions and the set of travel routes;

[0017] determining the position of the cable partial discharge according to the intersection of the set of possible positions and the set of travel routes.

[0018] Optionally, the calculating the position of the cable partial discharge includes:

[0019] The time difference of the response signals is calculated in at least two groups, and the receivers corresponding to the time difference of the response signals in the two groups are not completely the same;

[0020] calculating a set of possible positions of the cable partial discharge according to each group of time difference of the response signals, each group of time difference of the response signals corresponding to a set of possible positions;

[0021] calculating the intersection of a plurality of sets of possible positions;

[0022] determining the position of the cable partial discharge according to the intersection of a plurality of sets of possible positions.

[0023] Optionally, the calculating the position of the cable partial discharge further includes:

[0024] obtaining the position of the release point of the fault detection device and the current travel route of the fault detection device;

[0025] calculating the current position of the fault detection device on the cable;

[0026] obtaining the relative position of the cable partial discharge with respect to the fault detection device;

[0027] calculating the relative position of the cable partial discharge with respect 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 cable partial discharge.

[0028] Optionally, the calculating the position of the cable partial discharge further includes:

[0029] obtaining the time when the receiver that first receives the ultrasonic signal generates a response signal, and the travel speed of the fault detection device at that time;

[0030] obtaining the time difference between the time when the receiver that first receives the ultrasonic signal generates a response signal and the time when the other receivers generate response signals;

[0031] The time difference is corrected according to the travel speed of the fault detection device.

[0032] The application also provides a line loss fault point positioning system for electric power engineering construction, comprising a bearing and a processing unit, the bearing is provided with a driving unit for driving the bearing to move on a cable, and an ultrasonic wave receiving unit for detecting local discharge of the cable, the ultrasonic wave receiving unit has at least two;

[0033] The processing unit is in signal connection with the driving unit and the multiple ultrasonic wave receiving units;

[0034] One end of the bearing has a bending head for pressing the cable to bend, at least one ultrasonic wave receiving unit is located outside the bottom of the bending head, and at least one ultrasonic wave receiving unit is located outside the top of the bending head.

[0035] Optionally, the bottom of the bending head is provided with a deformation groove capable of accommodating the cable and providing a deformation space for the cable, the inner side surface of the deformation groove is a fitting surface of the cable, the included angle between the central axis of the deformation groove and the central axis of the bearing is obtuse, and the opening of the deformation groove away from the bearing is located above the bearing.

[0036] Optionally, the bottom of the bending head is provided with a suspension piece.

[0037] Optionally, the driving unit comprises a driving motor and a driving wheel connected to the rotating shaft of the driving motor and used for contacting the cable, and the driving motor is in signal connection with the processing unit.

[0038] In summary, the application has the following beneficial technical effects:

[0039] The application forces the line loss fault point with a discharge tendency to discharge by pressing the cable in real time, adopts the ultrasonic wave as a characteristic signal to obtain the time difference, eliminates the interference of background electric field and magnetic field, does not need power-off operation, and can accurately position the line loss fault point caused by local discharge, thereby reducing the difficulty of fault troubleshooting and the situation of missed detection. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 is a schematic diagram of a detection arrangement of the application;

[0041] Figure 2 is a schematic diagram of local discharge of a bending part of a cable to be detected according to the application;

[0042] Figure 3 is a schematic diagram of positioning of a line loss fault point of local discharge of a cable to be detected according to the application;

[0043] Figure 4 is a schematic diagram of positioning of a line loss fault point of local discharge according to the application by relying on a travel route.

[0044] Figure 5 is a schematic diagram of the partial discharge fault point positioning of the application relying on multiple groups of receivers;

[0045] Figure 6 is a schematic diagram of the arrangement of the positioning system of the application;

[0046] Figure 7 is a schematic diagram of the positioning system of the application compressing the cable to generate a bending part.

[0047] Reference signs: 10, carrier; 11, bending head; 12, deformation groove; 13, overhanging part;

[0048] 20, processing unit;

[0049] 30, driving unit; 31, driving motor; 32, driving wheel;

[0050] 40, ultrasonic receiving unit. DETAILED DESCRIPTION

[0051] The application will be further described in detail below in combination with the drawings.

[0052] In order to more clearly understand the technical solutions exhibited by the embodiments of the application, first, the partial discharge of the transmission line cable in power engineering construction is simply introduced.

[0053] When the cable insulation layer is manufactured, it may have inclusions and cavities inside. The inclusion and cavity defects in the cable insulation layer can be regarded as an equivalent capacitor. When there is current passing through the cable, charges are accumulated on the two ends of the equivalent capacitor. When the charge amount accumulated on the two ends of the equivalent capacitor exceeds the limit, or the voltage between the two ends of the equivalent capacitor exceeds the limit, the equivalent capacitor will break down. The equivalent capacitor temporarily becomes a path, which is manifested as a partial discharge line loss phenomenon of the cable. At this time, ultrasonic waves will be released.

[0054] When the equivalent capacitor discharges, the voltage between the two ends of the equivalent capacitor returns to the extinguishing voltage. With the continuous passage of current, charges continue to accumulate on the two ends of the equivalent capacitor. Until the voltage between the two ends of the equivalent capacitor exceeds the initial discharge voltage, the equivalent capacitor continues to start discharging.

[0055] In order to be able to accurately locate the line loss fault point caused by the partial discharge of the equivalent resistance defect in the cable without stopping the power of the transmission line, the embodiments of the application provide a line loss fault point positioning method for power engineering construction, which comprises the following steps:

[0056] S101, placing a fault detection device on the cable and walking;

[0057] S102, the fault detection device compresses the cable to bend the cable to be tested, the cable to be tested is bent to form a bending part, and the discharge point in the bending part is discharged;

[0058] 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;

[0059] S104, calculating the difference between the initial generation time of the response signal of the two receivers;

[0060] S105, calculating the position of the partial discharge of the cable according to the difference between the initial response time of the response signal of the two receivers.

[0061] In the following, combined with a specific use scenario, taking the case of partial discharge of the cable caused by the cavity in the cable insulation layer as an example, the technical solutions displayed by the embodiments of the present application are further introduced. Of course, in addition to being effective for the case of partial discharge of the cable caused by the cavity in the cable insulation layer, the embodiments of the present application are still effective for detecting and positioning the partial discharge phenomenon caused by other defects in the cable insulation layer.

[0062] Firstly, step S101 is performed, the fault detection device is released, the fault detection device has a plurality of ultrasonic receivers for receiving ultrasonic signals, which can be used to detect the ultrasonic signals generated by the partial discharge of the cable to be tested, and the arrangement pattern of the ultrasonic receivers can refer to Figure 1 The released fault detection device moves on the cable in a certain direction;

[0063] In step S102, referring to Figure 2 The fault detection device moves on the cable to be tested, and the cable is deformed under the influence of the weight of the fault detection device. The cable near the end of the fault detection device deforms most severely, and the cable at the aforementioned position is bent to form a bending part of the cable.

[0064] According to the description of the equivalent capacitance, it can be found that the breakdown effect of the equivalent capacitance depends on the accumulation of the charge amount on the capacitor screen at both ends. When the charge amount on the capacitor screen at both ends of the equivalent capacitance does not exceed the limit, the equivalent capacitance will not break down. In the prior art, when the instrument for detecting partial discharge passes through the area where partial discharge does not occur temporarily but has a tendency to occur, this area is skipped. The reason is that there is no specific identifiable feature for detecting partial discharge. After the instrument for detecting partial discharge leaves the aforementioned area and the equivalent capacitance breaks down, the instrument cannot detect the partial discharge signal. This is also the reason why it is difficult to check the point-to-point line loss fault point of the cable in the prior art, and there are more missed cases.

[0065] In the embodiment of the present application, the fault detection device compresses the cable to be tested to make part of the cable to be tested bend and deform into a bending part, and the shape of the cavity inside the insulation layer of the cable bending part will also change. In the case that the cavity is located on the side of the insulation 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 inner end faces is reduced. The gap of the part of the cavity away from the fault detection device is expanded, and the distance between the two inner end faces is increased. In the case that the cavity is located on the side of the insulation layer away from the fault detection device, the gap of the part of the cavity away from the fault detection device is sharply expanded, and the increment of the expansion is greater than that of the part of the cavity close to the fault detection device. Regardless of which of the above two cases the cavity is in, it will cause the continuous reduction of the facing area of the capacitor screen on both ends of the equivalent capacitor. In the case that the voltage is loaded on both ends of the cable, the amount of charge attached to both ends of the equivalent capacitor does not decrease, so that the breakdown voltage limit of the equivalent capacitor is significantly reduced due to the bending of the cable, thereby forcing the equivalent capacitor to break down and discharge.

[0066] 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 the breakdown limit of the cavity equivalent capacitor on both ends of the cable bending part are significantly reduced, thereby significantly reducing the period time of the equivalent capacitor charge and discharge. This makes the fault detection device in the embodiment of the present application always be able to detect the discharge of most defects in the cable during travel, reduces the probability of missed detection, and reduces the difficulty of troubleshooting of fault points.

[0067] Then step S103 is performed. After the equivalent capacitor discharges, 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 acquired and recorded, that is, the initial time when the response signal of each receiver is generated is acquired and recorded. In the embodiment of the present application, ultrasonic waves are used as characteristic signals for detection and positioning, instead of using pulse or magnetic field signals emitted when the cable line loss fault occurs as characteristic signals, which eliminates the interference of background electric field and magnetic field in actual use scenarios.

[0068] In step S104, the time difference between the initial generation times of the response signals of the two receivers is calculated.

[0069] Finally, step S105 is performed, referring to Figure 3 , the position of the local discharge of the cable is calculated according to the difference between the initial response times of the response signals of the two receivers, the distribution state and the position of the cable to be tested, and the precise positioning of the line loss fault point caused by the local discharge of the cable is realized.

[0070] In addition to the positioning mode relying on the current position and state of the cable described in step S105, in the embodiment of the application, the cable line loss fault point is positioned by calculating the time difference value of the initial generation time of the response signals of the two receivers, and there are at least two implementable forms. In order to facilitate description and illustration, the dimension reduction is used in the specific use scenario in a projected manner, and the dimension reduction is used to illustrate the point position of the line loss fault point in the actual use scenario. Of course, if it is necessary to position the line loss fault point of the cable in three dimensions, the method shown in the embodiment of the application is also applicable, and the difference lies only in the dimension of the identifiable feature vector:

[0071] With reference to Figure 4 One of the implementable forms includes the following steps:

[0072] Step S201: calculating a possible position set of the cable partial discharge according to the time difference value of the response signals between the two receivers, in the dimension-reduced example scenario, specifically, the element in the possible position set is a set of position coordinates where the partial discharge characteristic signal may exist, and the foregoing 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 do not necessarily lie on the cable, and the position coordinates where the partial discharge characteristic signal may exist are for the receivers;

[0073] In the dimension-reduced example scenario, since the distance and position relationship between the receivers on the fault detection device are fixed, the ultrasonic signals are received by the receivers in the medium, and the time difference between the two receivers receiving the determined ultrasonic signal can be obtained by calculation. Therefore, only for the receiver group composed of the two receivers, the possible position set is expressed in a graph, which is actually a hyperbola between the two receivers. The two foci of the hyperbola are the positions of the two receivers in the receiver group, and each point on the hyperbola is a position coordinate where the partial discharge characteristic signal may exist.

[0074] Step S202: obtaining a current route set of the fault detection device, the path of the fault detection device in the specific running process is a curve, and the foregoing current route set should be the path line between the initial release position and the current position of the fault detection device. Each point on the foregoing path line is an element in the current route set of the fault detection device. The path line described in the current route set of the fault detection device can be based on the central axis of the cable to be measured or based on the part actually contacted by the fault detection device and the cable. In actual acquisition of the current route set of the fault detection device, the current position coordinates of the fault detection device can be periodically collected, and then fitted.

[0075] Step S203: Calculate the intersection of the set of possible locations and the set of travel routes. Alternatively, it can be understood as calculating the elements in the set of possible locations that satisfy the constraints of the set of travel routes.

[0076] Step S204: Determine the location of the partial discharge point on the cable based on the intersection of the set of possible locations and the set of travel routes. The location of the partial discharge point on the cable is also the intersection element of the set of possible locations and the set of travel routes.

[0077] This detection and location method can pinpoint the fault point caused by partial discharge in the cable under test with only two calculations. The location is accurate to the exact location of the cable, and the calculation speed is fast and the efficiency is high.

[0078] Reference Figure 5 Another possible approach includes the following steps:

[0079] Step S301: The fault detection device has at least three receivers capable of receiving ultrasonic waves. The three receivers can form three receiver groups. Each receiver group has two receivers. The receiver numbers in several receiver groups are not completely the same. At least two receiver groups work simultaneously. When collecting the difference in the time of generation of the initial response signal, at least two groups are collected. That is, at least two groups of difference in the time of generation are calculated. The receivers corresponding to the difference in the time of generation of the two groups are not completely the same.

[0080] Step S302: Calculate the possible location set of partial discharge in the cable based on the difference between the generation times of each group. Each difference between the generation times corresponds to a possible location set. Taking the possible location set obtained by two groups of receivers as an example, each group of receivers has one of the hyperbolas with the two receivers as the focus. Each point on the hyperbolas is an element of the aforementioned possible location set, and the position coordinates of the element are represented by a two-dimensional vector.

[0081] Step S303: Calculate the intersection of multiple sets of possible locations. In the case of a graphical representation, it can be found that two sets of receivers can form two intersecting hyperbolas. The focus of the two hyperbolas with different focal positions is the intersection of the sets of possible locations.

[0082] Step S304: Determine the location of the partial discharge point on the cable based on the intersection of multiple sets of possible locations, that is, the focus of two hyperbolas with not exactly the same focus positions.

[0083] This detection and location method calculates the possible locations of the two sets of receivers, independent of the path of the fault detection device, and can pinpoint the fault point to a specific location on the cable with high accuracy.

[0084] Overall, the embodiments of the present application are to discharge the line loss fault point of the cable with discharge tendency by real-time compression cable, and to obtain time difference of arrival by using ultrasonic wave as characteristic signal, which excludes the interference of background electric field and magnetic field, without power outage operation, and can accurately locate the line loss fault point caused by partial discharge, reducing the difficulty of fault troubleshooting and missed detection.

[0085] As a feasible specific implementation of the embodiments of the present application, the calculation of the position of the cable partial discharge further comprises:

[0086] Step S401: Obtain the position of the release point of the fault detection device and the current 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 route of the fault detection device, and the current route of the fault detection device can be obtained 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 foregoing collected coordinate points into a curve, thereby forming the current route of the fault detection device;

[0087] Step S402: The starting point and the current route obtained in step S401 are used to easily calculate the position of the fault detection device relative to the starting point;

[0088] Step S403: Obtain the relative position of the cable partial discharge point relative to the fault detection device;

[0089] Step S404: According to the current position of the fault detection device and the relative position of the cable partial discharge point, the relative position of the cable partial discharge point relative to the release point of the fault detection device is calculated.

[0090] In the embodiments of the present application, the position information of the starting point of the fault detection device and the current route of the fault detection device are obtained, the position information of the cable fault point relative to the current position of the fault detection device is converted into the position information of the initial release point which is relatively fixed, so that after the entire cable is detected, the operator can clearly and easily find the determined position of the cable fault point.

[0091] It can be understood that the fault detection device moves on the cable to be detected, and in an ideal state, the fault detection device does not slip with the cable to be detected, so that the total travel route length of the fault detection device should be equal to the length of the detected region of the cable to be detected, in other words, in the case of taking the current position point of the fault detection device as a determination point, the current travel route of the fault detection device is intercepted with the determination point and the initial release point as end points, so that the curve length between the two points is determined, and after the fault detection device is removed from the cable to be detected, the operator can determine the current position point of the fault detection device on the cable to be detected according to the length of the aforementioned intercepted route, even if the fault detection device has been removed.

[0092] Of course, in the actual use scene, the fault detection device inevitably slips with the cable to be detected, and in the embodiment of the present application, the current travel route of the fault detection device is fitted by periodically collecting the current position point of the fault detection device, so that the position of the fault detection device on the cable to be detected before the fault detection device is removed still meets the requirements.

[0093] As a feasible specific implementation manner of the embodiment of the present application, the calculation of the position of the partial discharge of the cable further includes:

[0094] Step S501: If the plurality of receivers are unevenly distributed, when the partial discharge occurs at the bending part of the cable to be detected, the plurality of receivers receive the ultrasonic signals at different times, so that the plurality of receivers generate response signals at different times, at this time, the time when the response signal of the receiver that first receives the ultrasonic signal is generated is obtained, and the travel speed of the fault detection device at this time is obtained.

[0095] Step S502: The time difference between the time when the response signal of the receiver that first receives the ultrasonic signal is generated and the time when the response signal of the other receiver is generated is obtained.

[0096] Step S503: The time difference is corrected according to the travel speed of the fault detection device.

[0097] It can be understood that when the ultrasonic excitation signal propagates in the air medium at a certain speed, the fault detection device also travels, and the time difference between the response signals of the two ultrasonic receivers is the result of the joint action of the propagation of the ultrasonic excitation signal and the travel of the fault detection device, that is, the travel of the fault detection device will make the time difference between the two receivers higher, and the correction of the time difference can effectively improve the positioning accuracy of the cable partial discharge line loss fault point.

[0098] In some possible implementation manners of the embodiments of the present application, the offset displacement of the fault detection device moving in the aforementioned time difference is calculated first, then the required time for the ultrasonic signal to propagate the offset displacement length is calculated, and finally the time difference is corrected by subtracting the required time.

[0099] The embodiments of the present application also provide a line loss fault point positioning system for power engineering construction, which is a hardware support and implementation platform of the aforementioned line loss fault point positioning method for power engineering construction, and corresponds to the fault detection device in the method as a whole. Figure 6 and Figure 7 In detail, the line loss fault point positioning system for power engineering construction comprises a processing unit 20 for processing data and calculation, and a carrier 10 as a mounting base of an accessory, the carrier 10 is provided with a driving unit 30 for driving the carrier 10 to move on a cable, and an ultrasonic receiving unit 40 for detecting partial discharge of the cable, the ultrasonic receiving unit 40 has at least two.

[0100] The processing unit 20 is in signal connection with the driving unit 30 and the plurality of ultrasonic receiving units 40.

[0101] One end of the carrier 10 has a bending head 11 for pressing the cable to bend, the plurality of ultrasonic receiving units 40 are different in distance from the bending head 11, 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.

[0102] In use, the carrier 10 moves on the cable to be measured, the cable to be measured is bent at the part of the bending head 11 due to the self-weight of the carrier 10 and the accessory mounted on the carrier 10, the equivalent capacitance in the cable to be measured is forced to discharge, the ultrasonic signal released by the partial discharge is recognized by the ultrasonic receiving unit 40 and an excitation signal is generated, and the processing unit 20 can control the work of each component, accept the work parameters of each component, and calculate the received parameters.

[0103] In the embodiments of the present application, the bending head 11 is provided with a deformation groove 12 at the bottom, which can accommodate the cable and provide a deformation space for the cable, the inner side surface of the deformation groove 12 is a fitting surface of the cable, the included angle between the central axis of the deformation groove 12 and the central axis of the carrier 10 is an obtuse angle, and the opening of the deformation groove 12 away from the carrier 10 is located above the carrier 10, when the carrier 10 moves above the cable to be measured, the part of the cable to be measured located at the bending head 11 is bent, of course, the bending head 11 can also be provided with a pendant 13, so that the gravity center of the fault detection device is close to the bottom of the bending head 11.

[0104] The driving unit 30 is an actuator for moving the driving fault detection device on the cable to be detected, and specifically can include a driving motor 31 and a driving wheel 32 connected to the rotating shaft of the driving motor 31 and used for contacting the cable. The driving motor 31 is in signal connection with the processing unit 20. After the processing unit 20 sends an opening instruction to the driving motor 31, the driving motor 31 drives the driving wheel 32 to rotate. The driving wheel 32 is in frictional connection with the outer side of the insulation layer of the cable to be detected, so that the driving fault detection device moves on the cable to be detected.

[0105] The embodiments of the present specific implementation are the preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. Therefore, any equivalent changes made according to the structure, shape, principle of the present application should be covered within the protection scope of the present application.

Claims

1. A method for locating line loss fault points during power engineering construction, characterized in that, include: Release the fault detection device to allow it to travel along a defined direction on the cable; the fault detection device has multiple ultrasonic receivers. The fault detection device presses the cable, causing the cable under test to bend and form a bend, which causes the fault point inside the bend to discharge. Obtain the moment when the receiver generates the response signal to partial discharge in the cable; Calculate the difference in the time of generation of the response signals from the two receivers; The location of partial discharge in the cable is calculated based on the time difference of the response signals between the two receivers. The locations of partial discharge points in the computational cable include: Based on the time difference of the response signals between the two receivers, calculate the set of possible locations of partial discharge in the cable; Obtain the current travel route set of the fault detection device; Calculate the intersection of the set of possible locations and the set of travel routes; The location of the partial discharge point on the cable is determined by the intersection of the set of possible locations and the set of travel routes.

2. The method for locating line loss fault points in power engineering construction according to claim 1, characterized in that, The locations of partial discharge points in the computational cable include: The difference in the generation time is calculated in at least two sets, and the receivers corresponding to the difference in the two sets of generation times are not exactly the same. The possible locations of partial discharge on the cable are calculated based on the difference between the times of generation for each group, with each difference between the times of generation corresponding to a possible location set. Calculate the intersection of the multiple sets of possible locations; The location of the partial discharge point on the cable is determined by the intersection of multiple sets of possible locations.

3. The method for locating line loss fault points in power engineering construction according to claim 2, characterized in that, The location of the partial discharge point in the computing cable also includes: Obtain the location of the fault detection device's release point and the current travel route of the fault detection device; Calculate the current position of the fault detection device on the cable; Obtain the relative position of the partial discharge point on the cable with respect to the fault detection device; Based on the current location of the fault detection device and the relative location of the partial discharge point on the cable, calculate the relative position of the partial discharge point on the cable with respect to the release point of the fault detection device.

4. The method for locating line loss fault points in power engineering construction according to claim 3, characterized in that, The location of the partial discharge point in the computing cable also includes: Obtain the time when the receiver first receives the ultrasonic signal and the travel speed of the fault detection device at that time; Obtain the time difference between the moment when the receiver first receives the ultrasonic signal and the moment when the response signal is generated by other receivers; The time difference is corrected according to the travel speed of the fault detection device.

5. A system for locating line loss fault points in power engineering construction as described in claim 1, characterized in that, It includes a carrier and a processing unit. The carrier is equipped with a drive unit for driving the carrier to move on the cable and an ultrasonic receiving unit for detecting partial discharge of the cable. The ultrasonic receiving unit has at least two units. The processing unit is connected to the drive unit and multiple ultrasonic receiving units via signals. One end of the carrier has a bending head that compresses the cable to bend it, and at least one ultrasonic receiving unit is located on the outer side of the bottom of the bending head and at least one ultrasonic receiving unit is located on the outer side of the top of the bending head.

6. A line loss fault location system for power engineering construction according to claim 5, characterized in that, The bottom of the bending head has a deformation groove that can accommodate the cable and provide deformation space for the cable. The inner side of the deformation groove is the contact 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 at the end away from the carrier is located above the carrier.

7. A line loss fault location system for power engineering construction according to claim 5, characterized in that, A suspension component is provided at the bottom of the bending head.

8. A line loss fault location system for power engineering construction according to claim 5, characterized in that, The drive unit includes a drive motor and a drive wheel connected to the drive motor shaft for contacting cables. The drive motor is signal-connected to the processing unit.

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