A power transmission line distributed fault location method and system

Abstract

The application discloses a power transmission line distributed fault positioning method and system, non-contact type fault monitoring equipment is arranged at intervals on different towers to collect and store power frequency current, power frequency voltage and traveling wave current waveforms; contact type fault monitoring equipment is arranged on the power transmission line conductor to collect power frequency current, power frequency voltage and traveling wave current, whether the power transmission line is faulty is determined according to the collected power frequency current and power frequency voltage, when the power transmission line is faulty, the power frequency current and power frequency voltage fault waveforms for detection and the traveling wave current waveforms for fault positioning are sent; when the fault waveforms sent by the contact type fault monitoring equipment are received, the fault occurrence time is determined according to the fault waveforms, and the waveforms stored in a preset time interval before and after the fault occurrence time of all the non-contact type fault monitoring equipment are recalled; the fault position is determined according to the fault waveforms, the traveling wave current waveforms and the stored waveforms, and accurate judgment of the fault point position in the power transmission line is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power transmission line fault location, and particularly relates to a power transmission line distributed fault location method and system. BACKGROUND

[0002] After a fault occurs in a power transmission line, a fault location system is needed to quickly and accurately locate the fault point, so as to improve the patrol and maintenance efficiency of the fault point by maintenance personnel. In the traditional method, a traveling wave fault location device is usually arranged in a transformer substation, but when the power transmission distance is far, it is difficult to monitor the fault traveling wave information at a position far from the transformer substation.

[0003] In the prior art, a distributed fault monitoring device is installed to locate the fault position. The distributed fault monitoring device mainly has two types of contact type and non-contact type. The contact type fault monitoring device can directly collect three-phase currents and voltages of the power transmission line, and can accurately determine the fault line, fault phase and fault interval, but it needs to be installed during power outage or equipotential installation. However, it is difficult to power off the power transmission line, and the equipotential installation technology is difficult, resulting in low installation efficiency. Although the non-contact type fault monitoring device does not need to be installed during power outage, the sensor of the non-contact type fault monitoring device senses the electromagnetic signal in the space, which is a combined quantity of multiple conductors and is easily disturbed. Using the non-contact type fault monitoring device will bring the following problems: false alarm of fault start, unable to determine the fault phase, unable to determine the fault line for the same tower line, and unable to determine the fault interval for T-connected line main and branch line division, local division, etc. SUMMARY

[0004] The main purpose of the present application is to provide a power transmission line distributed fault location method and system, which aims to solve the technical problems of false judgment of fault and inability to accurately determine the fault conductor when using a non-contact type fault monitoring device for power transmission line fault location.

[0005] In a first aspect, the present application provides a power transmission line distributed fault location method, which comprises the following steps:

[0006] The non-contact type fault monitoring device arranged at intervals on different towers of the power transmission line between two transformer substations is used to collect and store the waveforms of power frequency current, power frequency voltage and traveling wave current;

[0007] The contact type fault monitoring device arranged on the conductors of the power transmission line between the two transformer substations is used to collect power frequency current, power frequency voltage and traveling wave current, to determine whether a fault occurs in the power transmission line according to the collected power frequency current and power frequency voltage, and to send the fault waveforms of the power frequency current and power frequency voltage for detection and the traveling wave current waveforms for fault location when it is determined that a fault occurs in the power transmission line;

[0008] Upon receiving the fault waveform sent by the contact-type fault monitoring device, the time of fault occurrence is determined according to the fault waveform, and the waveforms of the power frequency current, the power frequency voltage and the traveling wave current stored by all the non-contact-type fault monitoring devices within a preset time interval before and after the time of fault occurrence are recalled;

[0009] The fault point position of the power transmission line is determined according to the fault waveform and the traveling wave current waveform sent by the contact-type fault monitoring device and the stored waveform sent by the non-contact-type fault monitoring device.

[0010] In some embodiments, when the power transmission line between the two substations has no territorial division point and is a non-T-connection type line, a set of the contact-type fault monitoring device is arranged on the conductor of the power transmission line between the two substations to collect the power frequency current and the power frequency voltage.

[0011] In some embodiments, when the power transmission line between the two substations has a territorial division point, a set of the contact-type fault monitoring device is arranged on the conductor of the power transmission line at each territorial division point to collect the power frequency current and the power frequency voltage.

[0012] When the power transmission line between the substations has a T-connection type line and the main line and the branch line need to be divided into sections, a set of the contact-type fault monitoring device is arranged on the conductor at the head of each T-connection type line branch line to collect the power frequency current and the power frequency voltage.

[0013] In some embodiments, a set of the contact-type fault monitoring device includes a plurality of contact-type fault monitoring units, and one contact-type fault monitoring unit is arranged on one conductor of the power transmission line.

[0014] In some embodiments, the non-contact-type fault monitoring device is arranged on the waist of the tower of the power transmission line tower, and the interval distance between the non-contact-type fault monitoring devices is 20-30 km.

[0015] In some embodiments, the determination of the fault point position of the power transmission line according to the fault waveform and the traveling wave current waveform sent by the contact-type fault monitoring device and the stored waveform sent by the non-contact-type fault monitoring device includes:

[0016] The conductor of the power transmission line where the fault occurs is determined according to the fault waveform sent by the contact-type fault monitoring device.

[0017] The fault point position of the conductor of the power transmission line where the fault occurs is determined according to the traveling wave current waveform sent by the contact-type fault monitoring device and the stored waveform sent by the non-contact-type fault monitoring device.

[0018] In a second aspect, the application further provides a distributed fault positioning system for a power transmission line, which includes:

[0019] The non-contact fault monitoring device is arranged at different towers of the power transmission line between the two substations, and is used for collecting and storing the waveforms of the power frequency current, the power frequency voltage and the traveling wave current.

[0020] The contact type fault monitoring device is arranged on the conductor of the power transmission line between the two substations, and is used for collecting the power frequency current, the power frequency voltage and the traveling wave current, determining whether the power transmission line has a fault according to the collected power frequency current and power frequency voltage, and sending the fault waveforms of the power frequency current and the power frequency voltage and the traveling wave current waveforms for fault positioning to the central station when it is determined that the power transmission line has a fault.

[0021] The central station is used for determining the time when the fault occurs according to the fault waveforms when the contact type fault monitoring device sends the fault waveforms, and recalling all the waveforms of the power frequency current, the power frequency voltage and the traveling wave current stored by all the non-contact fault monitoring devices within a preset time interval before and after the time when the fault occurs.

[0022] The central station is also used for determining the fault point position of the power transmission line according to the fault waveforms and the traveling wave current waveforms sent by the contact type fault monitoring device and the stored waveforms sent by the non-contact fault monitoring device.

[0023] In some embodiments, when the power transmission line between the two substations has no territorial division point and is a non-T type line, the power transmission line distributed fault positioning system comprises a set of the contact type fault monitoring devices arranged on the conductor of the power transmission line between the two substations.

[0024] In some embodiments,

[0025] When the power transmission line between the two substations has a territorial division point, the power transmission line distributed fault positioning system comprises the contact type fault monitoring devices corresponding to the number of the territorial division points, which are arranged on the conductor of the power transmission line at each territorial division point.

[0026] When the power transmission line between the two substations has a T type line, and the main line and the branch line need to be divided into sections, the power transmission line distributed fault positioning system comprises the contact type fault monitoring devices corresponding to the number of the T type lines, which are arranged on the conductor of the branch line at the head of each T type line.

[0027] In some embodiments, the non-contact fault monitoring device is arranged on the waist of the tower of the power transmission line tower, and the interval distance between the non-contact fault monitoring devices is 20-30 km.

[0028] The application provides a power transmission line distributed fault positioning method and system. The non-contact type fault monitoring device arranged at different towers of the power transmission line between two substations is used to collect and store the waveforms of power frequency current, power frequency voltage and traveling wave current. The contact type fault monitoring device arranged on the conductor of the power transmission line between the two substations is used to collect the power frequency current, power frequency voltage and traveling wave current. Whether the power transmission line has a fault is determined according to the collected power frequency current and power frequency voltage. When it is determined that the power transmission line has a fault, the fault waveforms of the power frequency current and power frequency voltage for detection and the traveling wave current waveforms for fault positioning are sent. When the fault waveforms sent by the contact type fault monitoring device are received, the time when the fault occurs is determined according to the fault waveforms, and the waveforms of the power frequency current, power frequency voltage and traveling wave current stored by all the non-contact type fault monitoring devices in the preset time interval before and after the time when the fault occurs are recalled. The fault point position of the power transmission line is determined according to the fault waveforms and traveling wave current waveforms sent by the contact type fault monitoring device and the stored waveforms sent by the non-contact type fault monitoring device, so that the conductor having a fault in the power transmission line and the fault point position of the conductor having a fault can be accurately determined, and the fault misjudgment can be avoided. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0030] Figure 1 A flowchart of a power transmission line distributed fault positioning method provided by the embodiments of the application is shown.

[0031] Figure 2 A schematic diagram of the setting position of the non-contact type fault monitoring device is shown.

[0032] Figure 3 A schematic diagram of the setting position of the contact type fault monitoring device at the territorial division point of the power transmission line and the T-shaped line is shown.

[0033] Figure 4 A schematic diagram of the structure of the power transmission line distributed fault positioning system is shown.

[0034] The implementation, functional features and advantages of the application will be further described with reference to the embodiments and the drawings. DETAILED DESCRIPTION

[0035] With reference to the drawings, the technical solutions in the embodiments of the present application will be clearly and completely described, obviously, the described embodiments are some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative work belong to the scope of protection of the present application.

[0036] The flow chart shown in the drawings is only an example, and does not necessarily include all the contents and operations / steps, nor does it necessarily be executed in the order described. For example, some operations / steps can be further decomposed, combined or partially merged, so that the actual execution order may be changed according to the actual situation.

[0037] The embodiments of the present application provide a power transmission line distributed fault location method and system. The power transmission line distributed fault location method is applied to the power transmission line distributed fault location system.

[0038] Some embodiments of the present application will be described in detail below with reference to the drawings. In the case of no conflict, the embodiments described below and the features in the embodiments can be combined with each other.

[0039] Please refer to Figure 1 , Figure 1 A flow chart of a power transmission line distributed fault location method provided by an embodiment of the present application is shown.

[0040] As Figure 1 shown, the method comprises steps S1 to S4.

[0041] Step S1, using non-contact fault monitoring devices arranged at intervals on different towers of the power transmission line between the two substations, collect and store the waveforms of power frequency current, power frequency voltage and traveling wave current.

[0042] It is worth noting that the power transmission line between the two substations is supported by a plurality of towers as Figure 2 shown. As Figure 2 shown, the non-contact fault monitoring device is installed at the waist position of the tower, and the non-contact fault monitoring devices are installed at different towers at intervals, and the interval distance is 20-30 km. A plurality of sensors and data storage modules are arranged in the non-contact fault monitoring device, so that the non-contact fault monitoring device can collect and store the power frequency current, power frequency voltage and traveling wave current in the form of signal waveform. The non-contact fault monitoring device is also configured with a wireless communication module capable of receiving and sending information. The structure and working principle of the fault monitoring device are not the focus of the present application, and will not be described here.

[0043] Step S2, using the contact type fault monitoring device set on the transmission line conductor between the two substations to collect power frequency current, power frequency voltage and traveling wave current, according to the collected power frequency current and power frequency voltage to determine whether the transmission line has a fault, and when it is determined that the transmission line has a fault, the fault waveform of the power frequency current and power frequency voltage for detection and the traveling wave current waveform for fault location are sent.

[0044] It is worth noting that the contact type fault monitoring device can monitor the power frequency current and power frequency voltage through the built-in multiple sensors, and analyze and determine whether the transmission line has a fault according to the monitored power frequency current and power frequency voltage. At the same time, the traveling wave current is monitored, and the contact type fault monitoring device can monitor the traveling wave current when the transmission line has a fault. The traveling wave current can be used for fault location. The contact type fault monitoring device sends the power frequency current, power frequency voltage and traveling wave current waveform for fault location to the center station through the internally set wireless communication module.

[0045] As a preferred embodiment, as shown in Figure 3 The transmission line usually crosses multiple regions, so one transmission line is divided and managed by multiple localities. When there is a local division point between the two substations, a set of contact type fault monitoring devices are set on the transmission line at each local division point to collect power frequency current and power frequency voltage. The number of contact type fault monitoring devices corresponds to the number of local division points.

[0046] It should be noted that because the transmission lines on both sides of the local division point may be managed by different localities, the contact type fault monitoring device will send the fault waveform of the power frequency current and power frequency voltage for detection to different center stations or data receiving devices.

[0047] Further, as shown in Figure 3 The transmission line may have a T-junction type line, which is a tower pole directing two transmission lines in different directions. When there is a T-junction type line on the transmission line between the substations, and the main line and the branch line need to be divided, a set of contact type fault monitoring devices are set on the conductor at the head of each T-junction type line branch line to collect power frequency current and power frequency voltage. Similarly, the number of contact type fault monitoring devices corresponds to the number of T-junction type lines. In this way, the installation ensures that the contact type fault detection device has an accurate monitoring interval.

[0048] Further, when there is no local division point between the two substations and the transmission line is not a T-junction type line, a set of contact type fault monitoring devices are set on the conductor between the two substations to collect power frequency current and power frequency voltage.

[0049] As Figure 4As shown in the figure, one set of contact fault monitoring equipment includes multiple contact fault monitoring units, and one contact fault monitoring unit is arranged on one conductor of the power transmission line. For example, the power transmission line is a three-phase power transmission line, and one contact fault monitoring unit is installed on each phase of the power transmission line. Therefore, one set of contact fault monitoring equipment includes three contact fault monitoring units.

[0050] It is worth noting that the contact fault monitoring equipment in the embodiment of the present application sends the fault waveform of the power frequency current and the power frequency voltage for detection and the traveling wave current waveform for fault location, which is received by the central station. The central station can be a receiving device with data processing function. It is a prior art to determine whether the power transmission line has a fault according to the power frequency current and the power frequency voltage, which will not be described here.

[0051] Step S3, when receiving the fault waveform sent by the contact fault monitoring equipment, determining the fault occurrence time according to the fault waveform, and recalling the power frequency current, power frequency voltage and traveling wave current waveform stored by all the non-contact fault monitoring equipment within a preset time interval before and after the fault occurrence time.

[0052] Step S4, determining the fault point position of the power transmission line according to the fault waveform and the traveling wave current waveform sent by the contact fault monitoring equipment and the stored waveform sent by the non-contact fault monitoring equipment.

[0053] Specifically, the central station determines the conductor of the power transmission line that has a fault according to the fault waveform sent by the contact fault monitoring equipment. Since one contact fault monitoring unit is installed on each conductor of the power transmission line, the central station can determine the conductor that has a fault according to the contact fault monitoring unit that sends the fault waveform.

[0054] Further, the central station determines the fault point position of the conductor of the power transmission line according to the stored waveform sent by the non-contact fault monitoring equipment. Since the non-contact fault monitoring equipment is arranged at intervals, when the conductor of the power transmission line has a fault, the non-contact fault monitoring equipment will also have abnormal waveform collection and storage. The non-contact fault monitoring equipment that has abnormal stored waveform can determine the approximate interval of the fault point, and then the contact fault monitoring equipment sends the traveling wave current waveform and the non-contact fault monitoring equipment sends the stored waveform to determine the precise fault point position of the conductor of the power transmission line that has a fault.

[0055] The cooperation of the contact type fault monitoring device and the non-contact type fault monitoring device in the embodiment of the application can determine the faulty conductor and the faulty phase of the power transmission line, which can avoid the false positives of the non-contact type device and the problem that the non-contact type fault monitoring device cannot determine the fault section and the local division of the T connection line. The number of the contact type device is greatly reduced, and the installation difficulty and cost are greatly reduced. The position of the fault point is determined according to the traveling wave current waveform sent by the contact type fault monitoring device and the stored waveform sent by the non-contact type fault monitoring device, and the accuracy of the fault point positioning of the power transmission line is improved.

[0056] Please refer to Figure 4 , Figure 4 The embodiment of the application provides a schematic diagram of a power transmission line distributed fault positioning system.

[0057] As shown in Figure 4 , the system comprises a center station, a non-contact type fault monitoring device and a contact type fault monitoring device.

[0058] The non-contact type fault monitoring device is arranged at different towers of the power transmission line between two substations at intervals, and is used for collecting and storing the waveforms of the power frequency current, the power frequency voltage and the traveling wave current;

[0059] The contact type fault monitoring device is arranged on the conductor of the power transmission line between the two substations, and is used for collecting the power frequency current, the power frequency voltage and the traveling wave current, determining whether the power transmission line has a fault according to the collected power frequency current and power frequency voltage, and sending the fault waveform of the power frequency current and the power frequency voltage and the traveling wave current waveform for fault positioning to the center station when it is determined that the power transmission line has a fault;

[0060] The center station is used for determining the time when the fault occurs according to the fault waveform when the contact type fault monitoring device sends the fault waveform, and recalling all the waveforms of the power frequency current, the power frequency voltage and the traveling wave current stored by all the non-contact type fault monitoring devices within a preset time interval before and after the time when the fault occurs;

[0061] The center station is also used for determining the position of the fault point of the power transmission line according to the fault waveform and the traveling wave current waveform sent by the contact type fault monitoring device and the stored waveform sent by the non-contact type fault monitoring device.

[0062] In some embodiments,

[0063] When there is a local division point between the two substations, the power transmission line distributed fault positioning system comprises a contact type fault monitoring device corresponding to the number of the local division points, which is arranged on the conductor of the power transmission line at each local division point.

[0064] When the transmission line between two substations has a T-type line, and the main line and the branch line need to be divided into sections, the distributed fault location system of the transmission line comprises a contact type fault monitoring device corresponding to the number of T-type lines, which is respectively arranged on the conductor at the first end of each T-type line branch.

[0065] In some embodiments, the non-contact type fault monitoring device is arranged on the waist of the tower of the transmission line tower, and the interval distance between the non-contact type fault monitoring devices is 20-30 km.

[0066] It should be noted that, for the convenience and brevity of description, the specific working processes of the system and each device, module and unit described above can refer to the corresponding processes in the foregoing embodiments, which will not be described here.

[0067] It should be noted that, in this paper, the term "including", "containing" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, article or system including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or includes elements inherent to such process, method, article or system. Without more limitations, the element defined by the statement "including a" does not exclude the presence of other identical elements in the process, method, article or system including the element.

[0068] The above-mentioned serial numbers of the embodiments of the present application are only for description, and do not represent the advantages and disadvantages of the embodiments. The above description is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present application, and these modifications or replacements should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for distributed fault location of a power transmission line, characterized in that, The method comprises the following steps: a non-contact fault monitoring device arranged on different towers of a transmission line between two substations collects and stores waveforms of power frequency current, power frequency voltage and traveling wave current; a contact fault monitoring device arranged on a conductor of the transmission line between the two substations collects power frequency current, power frequency voltage and traveling wave current, determines whether the transmission line has a fault according to the collected power frequency current and power frequency voltage, and sends fault waveforms of the power frequency current and power frequency voltage for detection and traveling wave current waveforms for fault location when it is determined that the transmission line has a fault; when the contact fault monitoring device sends the fault waveforms, the time when the fault occurs is determined according to the fault waveforms, and the waveforms of power frequency current, power frequency voltage and traveling wave current stored by all the non-contact fault monitoring devices within a preset time interval before and after the time when the fault occurs are recalled; the fault point position of the transmission line is determined according to the fault waveforms and traveling wave current waveforms sent by the contact fault monitoring device and the stored waveforms sent by the non-contact fault monitoring device; when the transmission line between the two substations has no territorial division point and is a non-T connection type line, a set of the contact fault monitoring device is arranged on a conductor of the transmission line between the two substations to collect power frequency current and power frequency voltage; when the transmission line between the two substations has a territorial division point, a set of the contact fault monitoring device is arranged on a conductor of the transmission line at the territorial division point to collect power frequency current and power frequency voltage; when the transmission line between the two substations has a T connection type line and the main line and the branch line need to be divided into sections, a set of the contact fault monitoring device is arranged on a conductor at the head of the branch line of the T connection type line to collect power frequency current and power frequency voltage.

2. The method for distributed fault location of a power transmission line according to claim 1, characterized in that, A set of the contact fault monitoring device comprises a plurality of contact fault monitoring units, and one contact fault monitoring unit is arranged on a conductor of the transmission line.

3. The distributed fault location method of the transmission line according to claim 1, wherein the non-contact fault monitoring devices are arranged on the waists of the towers of the transmission line, and the interval distance between the non-contact fault monitoring devices is 20-30 km.

4. The method for distributed fault location of power transmission lines according to claim 1, characterized in that, The method of determining the fault point position of the transmission line according to the fault waveforms and traveling wave current waveforms sent by the contact fault monitoring device and the stored waveforms sent by the non-contact fault monitoring device comprises the following steps: determining the conductor of the transmission line where the fault occurs according to the fault waveforms sent by the contact fault monitoring device; determining the fault point position of the conductor of the transmission line where the fault occurs according to the traveling wave current waveforms sent by the contact fault monitoring device and the stored waveforms sent by the non-contact fault monitoring device.

5. A power line distributed fault location system characterized by, The method comprises the following steps: a center station; non-contact fault monitoring devices arranged at intervals on different towers of a transmission line between two substations, which are used to collect and store waveforms of power frequency current, power frequency voltage and traveling wave current; The contact type fault monitoring device is arranged on the conductor of the transmission line between two substations, and is used to collect power frequency current, power frequency voltage and traveling wave current, determine whether the transmission line has a fault according to the collected power frequency current and power frequency voltage, and send the fault waveform of the power frequency current and the power frequency voltage and the traveling wave current waveform for fault positioning to the center station when it is determined that the transmission line has a fault; The center station is used to determine the time when the fault occurs according to the fault waveform when the center station receives the fault waveform sent by the contact type fault monitoring device, and recall all the power frequency current, power frequency voltage and traveling wave current waveforms stored by all the non-contact type fault monitoring devices within a preset time interval before and after the time when the fault occurs; The center station is also used to determine the fault point position of the transmission line according to the fault waveform and the traveling wave current waveform sent by the contact type fault monitoring device and the stored waveforms sent by the non-contact type fault monitoring device; When the transmission line between the two substations has no local division point and is a non-T type line, the transmission line distributed fault positioning system includes a set of contact type fault monitoring devices arranged on the conductor of the transmission line between the two substations; When the transmission line between the two substations has a local division point, the transmission line distributed fault positioning system includes a contact type fault monitoring device corresponding to the number of local division points, which is arranged on the conductor of the transmission line at each local division point; When the transmission line between the two substations has a T type line, and the main line and the branch line need to be divided into sections, the transmission line distributed fault positioning system includes a contact type fault monitoring device corresponding to the number of T type lines, which is arranged on the conductor at the head of each T type line branch.

6. The distribution system for locating faults on a power transmission line as defined in Claim 5 wherein , The non-contact type fault monitoring device is arranged on the waist of the tower of the transmission line tower, and the interval distance between the non-contact type fault monitoring devices is 20-30 km.

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