CN116087694A

CN116087694A - Method, device, electronic equipment and storage medium for determining cable fault position

Info

Publication number: CN116087694A
Application number: CN202310122120.8A
Authority: CN
Inventors: 罗威; 罗海波; 魏存良; 陈芳; 李志华; 李灵勇; 赖华兰; 潘旭扬
Original assignee: Guangdong Power Grid Co Ltd; Meizhou Power Supply Bureau of Guangdong Power Grid Co Ltd
Current assignee: Guangdong Power Grid Co Ltd; Meizhou Power Supply Bureau of Guangdong Power Grid Co Ltd
Priority date: 2023-02-14
Filing date: 2023-02-14
Publication date: 2023-05-09

Abstract

The invention discloses a method, a device, electronic equipment and a storage medium for determining a cable fault position. The method comprises the following steps: when a preset pulse wave acts on the cable, acquiring a first electric pulse signal corresponding to a first end of the cable and a second electric pulse signal generated at a second end of the cable; determining a reflection time length of the pulse wave reflected to the first end based on the first electric pulse signal, and determining a transmission time length of the pulse wave transmitted from the reflection start point to the second end based on the second electric pulse signal, so as to determine a time difference based on the reflection time length and the transmission time length; and determining the distance from the fault point in the cable to one end of the cable based on the length of the cable, the time difference and the conveying time length of the preset pulse wave from the first end to the second end. The problem of the prior art through discernment reflection pulse to cable fault location, lead to the fault location accuracy low is solved, the realization reaches the effect that improves the accuracy of confirming cable fault position.

Description

Method, device, electronic equipment and storage medium for determining cable fault position

Technical Field

The present invention relates to the field of power distribution networks, and in particular, to a method, an apparatus, an electronic device, and a storage medium for determining a cable fault location.

Background

In recent years, with the continuous expansion of the power grid scale and the continuous improvement of the voltage level, the safe and stable operation of the cable has important significance for ensuring the power supply reliability. Therefore, the fault of the power cable needs to be accurately positioned, the running state of the power cable is known timely, and the safe and stable running of the cable and the whole power system is ensured.

At present, a method for positioning a cable fault generally adopts a pulse transmitting device to transmit a pulse signal at a cable measuring end, and at the same time, a reflected pulse is detected at the measuring end, and after the reflected pulse is detected, the fault distance is calculated according to the time interval between the transmitted pulse and the reflected pulse and the wave speed, but because the reflection coefficient of a pulse traveling wave is small, the measuring end can hardly identify the reflected wave, so that the detection of the reflected wave is influenced, and the problem of low cable fault positioning accuracy is caused.

Disclosure of Invention

The invention provides a method, a device, electronic equipment and a storage medium for determining a cable fault position, which are used for improving the accuracy of determining the cable fault position and achieving the technical effect of guaranteeing safe and stable operation of a power grid.

According to an aspect of the present invention, there is provided a method of determining the location of a cable fault, the method comprising:

When a preset pulse wave acts on a cable, acquiring a first electric pulse signal corresponding to a first end of the cable and a second electric pulse signal generated at a second end of the cable; the first electric pulse signal comprises a forward electric pulse signal generated at the first end of the cable and a reflected pulse signal corresponding to the first electric pulse signal, and the preset pulse wave is transmitted from the first end to the second end;

determining a reflection time length of a pulse wave reflected to the first end based on the first electric pulse signal, and determining a transmission time length of the pulse wave transmitted from a reflection start point to the second end based on the second electric pulse signal, so as to determine a time difference based on the reflection time length and the transmission time length;

and determining the distance from a fault point in the cable to one end of the cable based on the length of the cable, the time difference and the conveying time length of the preset pulse wave from the first end to the second end, so as to determine the position information of the fault point in the cable based on the distance.

According to another aspect of the present invention, there is provided an apparatus for determining a location of a cable fault, the apparatus comprising:

The pulse signal acquisition module is used for acquiring a first electric pulse signal corresponding to a first end of the cable and a second electric pulse signal generated at a second end of the cable when a preset pulse wave acts on the cable; the first electric pulse signal comprises a forward electric pulse signal generated at the first end of the cable and a reflected pulse signal corresponding to the first electric pulse signal, and the preset pulse wave is transmitted from the first end to the second end;

the time difference determining module is used for determining the reflection time length of the pulse wave reflected to the first end based on the first electric pulse signal, and determining the transmission time length of the pulse wave transmitted from the reflection starting point to the second end based on the second electric pulse signal, so as to determine the time difference based on the reflection time length and the transmission time length;

and the distance determining module is used for determining the distance from the fault point in the cable to one end of the cable based on the length of the cable, the time difference and the conveying time length of the preset pulse wave transmitted from the first end to the second end, so as to determine the position information of the fault point in the cable based on the distance.

According to another aspect of the present invention, there is provided an electronic apparatus including:

at least one processor; and

a memory communicatively coupled to the at least one processor; wherein,,

the memory stores a computer program executable by the at least one processor to enable the at least one processor to perform the method of determining a cable fault location according to any one of the embodiments of the invention.

According to another aspect of the present invention, there is provided a computer readable storage medium storing computer instructions for causing a processor to perform the method for determining a cable fault location according to any one of the embodiments of the present invention.

According to the technical scheme, when the preset pulse wave acts on the first end of the cable, a first electric pulse signal corresponding to the first end of the cable and a second electric pulse signal generated at the second end of the cable are obtained; determining a reflection time length of the pulse wave reflected to the first end based on the first electric pulse signal, and determining a transmission time length of the pulse wave transmitted from the reflection start point to the second end based on the second electric pulse signal, so as to determine a time difference based on the reflection time length and the transmission time length; the method and the device have the advantages that the distance from the fault point in the cable to one end of the cable is determined based on the length and the time difference of the cable and the conveying time length of a preset pulse wave transmitted from the first end to the second end, so that the problem that the fault location accuracy is low due to the fact that the fault location of the cable is achieved through identifying the fault location of the reflected pulse based on the distance is solved, the fact that the preset pulse wave acts on the first end of the cable, the first electric pulse signal corresponding to the first end of the cable and the second electric pulse signal generated at the second end of the cable are collected, the time difference between the first reflection of the pulse wave to the first end and the time difference between the first reflection start point and the time of the transmission from the reflection start point to the second end is calculated, the time difference can be calculated through the electric pulse signals at the two ends of the cable, and the distance from the fault point to one end of the cable is determined based on the time difference, the length of the cable and the conveying time length of the first end to the second end is further, and the accuracy of determining the fault location of the cable is improved, and the technical effect of ensuring safe and stable operation of a power grid is achieved.

It should be understood that the description in this section is not intended to identify key or critical features of the embodiments of the invention or to delineate the scope of the invention. Other features of the present invention will become apparent from the description that follows.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a flow chart of a method of determining a location of a cable fault provided in accordance with a first embodiment of the present invention;

FIG. 2 is a flow chart of a method for determining the location of a cable fault provided in accordance with a second embodiment of the present invention;

fig. 3 is a waveform diagram for characterizing a pulse signal to be used according to a second embodiment of the present invention;

fig. 4 is a flowchart of a method for determining a location of a cable fault according to a third embodiment of the present invention;

fig. 5 is a schematic diagram for characterizing an electrical cable provided in accordance with a third embodiment of the present invention;

FIG. 6 is a schematic diagram of a method for determining a cable fault location according to a fourth embodiment of the present invention;

fig. 7 is a schematic structural view of an apparatus for determining a fault location of a cable according to a fifth embodiment of the present invention;

fig. 8 is a schematic structural diagram of an electronic device implementing a method for determining a cable fault location according to an embodiment of the present invention.

Detailed Description

In order that those skilled in the art will better understand the present invention, a technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.

It should be noted that the terms "first," "second," and the like in the description and the claims of the present invention and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the invention described herein may be implemented in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

Example 1

Fig. 1 is a flowchart of a method for determining a cable fault location according to a first embodiment of the present invention, where the present embodiment is applicable to a case of determining a cable fault point location, the method may be performed by a device for determining a cable fault location, where the device for determining a cable fault location may be implemented in hardware and/or software, and the device for determining a cable fault location may be configured in a computing device. As shown in fig. 1, the method includes:

s110, when a preset pulse wave acts on the cable, acquiring a first electric pulse signal corresponding to the first end of the cable and a second electric pulse signal generated at the second end of the cable.

The preset pulse wave may be a pulse signal with known parameters, for example, a voltage signal or a current signal. The cable includes a head end and a tail end, and the head end can be used as a first end, and the tail end can be used as a second end. The preset pulse wave is transmitted from the first end to the second end. The first electric pulse signal comprises a forward electric pulse signal generated at the first end of the cable and a reflected pulse signal corresponding to the first electric pulse signal. It should be noted that, a fault point may exist in the cable, and a pulse signal generated from the first end to the fault point may be used as a forward electric pulse signal after the pulse wave acts on the first end of the cable; the pulse signal generated when the fault point is reflected to the first end is taken as a reflected pulse signal.

In this embodiment, a signal generating source (such as a pulse generator) may be used to generate a pulse signal with a known parameter as a preset pulse wave, and the preset pulse wave may be applied to the first end circuit of the cable. Along with the transmission of the pulse wave in the cable circuit, the pulse signal can be detected at the second end of the cable, and the second electric pulse signal generated at the second end of the cable can be collected. And collecting the generated first electrical pulse signal at the first end of the cable conductor.

It should be noted that, in order to improve the accuracy of the test, the cable double-ended crystal oscillator clock may be corrected before the preset pulse wave acts on the cable. For example, the fault locating algorithm of high-precision Beidou time service can be combined to correct the first end and the second end crystal oscillator clocks of the cable, the output frequency of the crystal oscillator clocks is precisely measured and regulated, a high-precision time frequency reference signal is provided, and the requirement of an electric power system on relay protection is met.

For example, after the double-end crystal oscillator clock of the cable is corrected, the pulse generator can be controlled to generate pulse signals with known parameters, the pulse signals are injected from one end of the cable and act on the cable, the rogowski coil sensor can be used for collecting high-frequency signals, and current signals at the two ends of the cable are respectively collected to obtain a first electric pulse signal m (t) and a second electric pulse signal n (t). The rogowski coil has the characteristics of high-frequency response, linear output, wide frequency range and the like, can meet the requirement of high-frequency transient traveling wave, and improves the quality of sampled data.

S120, determining the reflection time length of the pulse wave reflected to the first end based on the first electric pulse signal, and determining the transmission time length of the pulse wave transmitted from the reflection starting point to the second end based on the second electric pulse signal, so as to determine the time difference based on the reflection time length and the transmission time length.

Wherein the first electric pulse signal contains current values acquired at a plurality of acquisition moments. The reflection start point corresponds to the cable fault point.

In this embodiment, the length of time that the traveling wave is reflected back to the first end for the first time from the cable fault point in the process of inputting the pulse wave from the first end to the second end can be resolved as the reflection length by analyzing the current value information in the first electric pulse signal. Similarly, the current value information in the second electric pulse signal can be analyzed, and the time length when the pulse wave is transmitted from the cable fault point, namely the reflection starting point, to the second end for the first time is analyzed as the transmission time length. The difference between the reflection time length and the transmission time length can be calculated, and the difference is taken as a time difference, so that the fault point position is calculated according to the time difference.

S130, determining the distance from a fault point in the cable line to one end of the cable line based on the length of the cable line, the time difference and the transmission time length of the preset pulse wave from the first end to the second end, so as to determine the position information of the fault point in the cable line based on the distance.

Wherein the length of the cable wire may refer to the distance from the first end to the second end.

In this embodiment, after the preset pulse wave acts on the first end of the cable, the arrival time of the pulse is detected at the second end, and the transmission time length of the pulse wave from the first end to the second end is determined as the transmission time length. And simultaneously the length of the cable can be measured. Further, the distance from the fault point in the cable to one end of the cable can be calculated by using the conveying time length, the conveying length and the conveying time difference. For example, a function for calculating the distance from the fault point in the cable to one end of the cable may be preconfigured, the conveying duration, the length and the time difference may be used as parameters of the function, and a distance value may be obtained, where the distance value may represent the distance from the fault point to the first end of the cable, and may also represent the distance from the fault point to the second end of the cable, so that the position information of the fault point in the cable may be accurately determined based on the distance value.

According to the technical scheme, when a preset pulse wave acts on the first end of the cable, a first electric pulse signal corresponding to the first end of the cable and a second electric pulse signal generated at the second end of the cable are obtained; determining a reflection time length of the pulse wave reflected to the first end based on the first electric pulse signal, and determining a transmission time length of the pulse wave transmitted from the reflection start point to the second end based on the second electric pulse signal, so as to determine a time difference based on the reflection time length and the transmission time length; the method and the device have the advantages that the distance from the fault point in the cable to one end of the cable is determined based on the length and the time difference of the cable and the conveying time length of a preset pulse wave transmitted from the first end to the second end, so that the problem that the fault location accuracy is low due to the fact that the fault location of the cable is achieved through identifying the fault location of the reflected pulse based on the distance is solved, the fact that the preset pulse wave acts on the first end of the cable, the first electric pulse signal corresponding to the first end of the cable and the second electric pulse signal generated at the second end of the cable are collected, the time difference between the first reflection of the pulse wave to the first end and the time difference between the first reflection start point and the time of the transmission from the reflection start point to the second end is calculated, the time difference can be calculated through the electric pulse signals at the two ends of the cable, and the distance from the fault point to one end of the cable is determined based on the time difference, the length of the cable and the conveying time length of the first end to the second end is further, and the accuracy of determining the fault location of the cable is improved, and the technical effect of ensuring safe and stable operation of a power grid is achieved.

Example two

Fig. 2 is a flowchart of a method for determining a fault location of a cable according to a second embodiment of the present invention, where S120 is further refined based on the foregoing embodiment. The specific implementation manner can be seen in the technical scheme of the embodiment. Wherein, the technical terms identical to or corresponding to the above embodiments are not repeated herein.

As shown in fig. 2, the method specifically includes the following steps:

s210, when a preset pulse wave acts on the cable, acquiring a first electric pulse signal corresponding to the first end of the cable and a second electric pulse signal generated at the second end of the cable.

S220, performing zero-phase filtering on the first electric pulse signal to obtain a pulse signal to be used.

Wherein the pulse signal to be used comprises a plurality of current values.

In this embodiment, after the first electric pulse signal is collected, zero-phase filtering processing may be performed on the first electric pulse signal, so as to obtain a filtered pulse signal, which is used as the pulse signal to be used. The benefits of this = setting are: after zero-phase filtering is adopted, no obvious distortion exists at the wave head and wave tail of the pulse signal, so that the searching of the starting position of the traveling wave head is facilitated, and the accuracy of the time for searching the fault traveling wave to reach the first end and the second end for the first time is improved.

Illustratively, the current signals M (t) and N (t) at the two ends of the cable are sampled and recorded, and then the zero-phase filtering is performed on the M (t) and the N (t) respectively, so as to obtain filtered signals M (t) and N (t).

S230, determining a preset number of current values from the pulse signals to be used according to a preset extraction rule, and obtaining a current set.

The preset extraction rule may be a rule that a preset number of current values are collected from front to back according to a time dimension. The preset number may be 400 or 500, and is not limited.

In this embodiment, a preset number of current values may be extracted from the pulse signal to be used, and these current values may be used as the current set. Illustratively, the first 500 current values in the pulse signal M (t) to be used are extracted.

S240, determining the reflection duration based on the pulse signal to be used, the maximum value of the current in the pulse signal to be used, the current set, the first preset value, the second preset value and the third preset value.

The first preset value, the second preset value and the third preset value are all preset parameter values, for example, the first preset value is 0.1, the second preset value is 1.2 and the third preset value is 0.05.

In the present embodiment, the respective current values in the pulse signal to be used may be compared, and the maximum value thereof may be found as the current maximum value, for example, the current maximum value vmax=max (M) in the reading M (t). Further, the reflection duration may be determined according to the pulse signal to be used, the current maximum value, the current set, the first preset value, the second preset value, and the third preset value, and the specific implementation manner may be: determining a minimum current value and a maximum current value in the current set; determining a current difference value based on the minimum current value and the maximum current value; the reflection duration is determined based on the pulse signal to be used, the current maximum value, the current difference value, the first preset value, the second preset value and the third preset value.

Specifically, the maximum current value can be found out from the current values in the current set, and the minimum current value can be found out. The maximum current value and the minimum current value are subjected to difference processing, and the obtained difference value can be used as a current difference value. For example, the first 500 current values of M (t) may be compared, the value Vmmax with the largest amplitude among the 500 current values is taken as the maximum current value, the value Vmmin with the smallest amplitude is taken as the minimum current value, and then the maximum value and the minimum value are differed to obtain a difference value as a current difference value vs= (Vmmax-Vmmin). Further, the time corresponding to the corresponding current value can be found from the pulse signal to be used through the current maximum value, the current difference value, the first preset value, the second preset value and the third preset value, and the reflection duration is determined based on the time.

In this embodiment, based on the pulse signal to be used, the current maximum value, the current difference value, the first preset value, the second preset value, and the third preset value, the implementation manner of determining the reflection duration may be: determining a first reference value based on the current maximum value, the current difference value, the first preset value and the second preset value; determining a second reference value based on the current difference and a third preset value; the reflection duration is determined based on the pulse signal to be used, the first reference value and the second reference value.

In practical application, the maximum value of the current and the first preset value are processed to obtain a first product value, the difference value of the current and the second preset value are processed to obtain a second product value, and then the first product value and the second product value are processed to obtain a sum value as the first reference value. The current difference and the third preset value may be integrated, and the resulting product may be used as the second reference value. The current value corresponding to the first reference value can be found out from the pulse signal to be used, and the acquisition time of the current value is determined. And then the current value corresponding to the second reference value is searched out from the pulse signal to be used reversely from the acquisition time, the acquisition time is determined, and the reflection time length can be determined through the acquisition time.

For example, the first preset value is 0.1, the second preset value is 1.2, the third preset value is 0.05, the first reference value is 0.1vmax+1.2vs, the second reference value is 0.05Vs, where Vmax is the current maximum value and Vs is the current difference.

In this embodiment, determining the reflection period based on the pulse signal to be used, the first reference value, and the second reference value includes: searching a first moment corresponding to a first current value larger than a first reference value from the pulse signals to be used according to the time dimension; reversely searching a current value from a first time in the pulse signal to be used, and determining a second time corresponding to the first current value smaller than a second reference value; the reflection duration is determined based on the start time and the second time in the pulse signal to be used.

Specifically, the current value can be searched from the front to the back in the pulse signal to be used, the first current value larger than the first reference value is searched, and the acquisition time of the current value is taken as the first time. Further, the current value is reversely and forwards searched from the pulse signal to be used from the first moment, the first current value smaller than the second reference value is searched, and the acquisition moment of the current value is taken as the second moment. Therefore, the starting time and the second time in the pulse signal to be used can be differenced, the difference value is taken as the reflection time length, for example, if the starting time is 0, the reflection time length is the recording time corresponding to the second time.

For example, referring to fig. 3, the abscissa axis represents the acquisition time, the ordinate axis represents the current value, and the X current value is found from the front to the back from the pulse signal to be used, where X satisfies: x > |0.1Vmax+1.2Vs|, and the acquisition time corresponding to X is the first time. Then, the current value S is found from the current value X, and the first current value S meets the following conditions: s < |0.05Vs|, and the acquisition time corresponding to S is the second time. S is the starting point of the traveling wave, and the corresponding time is tm1. And the same applies to tn1, which is the transmission time period between the reflection start point and the second end of the pulse wave.

S250, determining the transmission time length of the pulse wave from the reflection starting point to the second end based on the second electric pulse signal.

It should be noted that, the manner of determining the transmission time period from the reflection start point to the second end of the pulse wave is the same as the manner of determining the reflection time period from the pulse wave to the first end, and will not be described herein. The above-mentioned S220-S240 and S250 may be executed sequentially or may be executed in parallel, for example, S220-S240 may be executed first, S250 may be executed first, or both may be executed in parallel, and the specific execution sequence is not limited.

S260, determining a time difference based on the reflection time period and the transmission time period.

Specifically, after determining the reflection time period tm1 for the pulse wave to reflect to the first end and determining the transmission time period tn1 for the pulse wave to transmit from the reflection start point to the second end, the reflection time period and the transmission time period may be differenced to obtain a time difference, such as a time difference Δt1=tm1-tn 1.

S270, determining the distance from the fault point in the cable to one end of the cable based on the length of the cable, the time difference and the transmission time length of the preset pulse wave from the first end to the second end, so as to determine the position information of the fault point in the cable based on the distance.

According to the technical scheme, the first electric pulse signal is subjected to zero-phase filtering to obtain a signal to be used, so that signals with distortion existing in the wave head and wave tail of the filtered pulse signal are obviously filtered, a preset number of current values are determined from the pulse signal to be used according to a preset extraction rule to obtain a current set, and then the reflection duration is determined based on the pulse signal to be used, the maximum value of the current in the pulse signal to be used, the current set, the first preset value, the second preset value and the third preset value, so that the time difference is determined based on the reflection duration and the transportation duration, the determination of the time difference that the fault pulse reaches the two ends of the cable for the first time can be realized without detecting the reflection pulse, and the effect of improving the safety operation of a power grid is achieved while improving the fault positioning accuracy.

Example III

Fig. 4 is a flowchart of a method for determining a fault location of a cable according to a third embodiment of the present invention, where S130 is further refined based on the foregoing embodiment. The specific implementation manner can be seen in the technical scheme of the embodiment. Wherein, the technical terms identical to or corresponding to the above embodiments are not repeated herein.

As shown in fig. 4, the method specifically includes the following steps:

s310, when a preset pulse wave acts on the cable, a first electric pulse signal corresponding to the first end of the cable and a second electric pulse signal generated at the second end of the cable are obtained.

S320, determining a reflection time length of the pulse wave reflected to the first end based on the first electric pulse signal, and determining a transmission time length of the pulse wave transmitted from the reflection starting point to the second end based on the second electric pulse signal, so as to determine a time difference based on the reflection time length and the transmission time length.

S330, determining the transmission speed corresponding to the preset pulse wave based on the length of the cable and the transmission time length.

The traveling wave velocity v is related to only the characteristics of inductance, capacitance, etc. of the line unit length, and is not related to the characteristics of the wave signal itself, so the transmission velocity of the fault traveling wave on the section of cable line can be calculated by using the known pulse signal.

In this embodiment, the length of the cable wire and the conveyance time period may be processed as a quotient, and the quotient may be used as the conveyance speed. For example, referring to fig. 5, the cable length may be measured and recorded as L, the time difference between the pulse signal passing through the two ends (the M end and the N end) is measured to be Δt, the cable line length L is known, and the speed of traveling wave transmission on the section of line is determined by using the time difference between the two ends, where the transmission speed v=l/Δt.

S340, determining the distance based on the length, the time difference and the transmission speed.

In practical application, after the time difference between the fault traveling wave initially reaching the first end and the second end can be calculated through a difference method, the distance from the fault point to one end of the cable line can be calculated through the length, the time difference and the transmission speed, so that the position of the fault point can be calculated. Specifically, based on the length, time difference, and transmission speed, the implementation of determining the distance may be: determining a first intermediate value based on the time difference and the transmission speed; determining a second intermediate value based on the length and the first intermediate value; the distance is determined based on the second intermediate value and the fourth preset value.

In this embodiment, the time difference and the transmission speed may be multiplied, the multiplied value is used as a first intermediate value, and further, the length and the first intermediate value may be added to obtain a sum value as a second intermediate value. And processing the second intermediate value and the fourth preset value as a quotient, wherein the quotient can be taken as the distance. For example, with continued reference to fig. 5, the distance xm= (l+Δt1×v)/2, where 2 is a fourth preset value, and Xm represents the distance from the fault point P in the cable to the one end M of the cable.

According to the technical scheme, the transmission speed corresponding to the preset pulse wave is determined based on the length and the transmission duration of the cable; based on the length, the time difference and the transmission speed, the distance from the fault point in the cable to one end of the cable is determined, and the accuracy of cable fault positioning is improved.

Example IV

As an alternative embodiment to the above embodiment, fig. 6 is a schematic diagram of a method for determining a location of a cable fault according to a fourth embodiment of the present invention. In particular, reference may be made to the following details.

Referring to fig. 6, in the technical solution provided in this embodiment, the implementation manner of determining the cable fault location may be: firstly, a fault positioning algorithm of high-precision Beidou time service is combined to correct a crystal oscillator clock at two ends (a first end M and a second end N) of a cable, and the length L of the cable is measured. Then, pulse signals with known parameters are generated by a pulse generator, pulse arrival time is detected at the other end of the cable, the time difference between the two ends of the pulse signals is measured to be deltat, and the transmission speed v of the pulse wave acting on the cable on the section of the line is determined by using the time difference between the two ends, wherein the speed v=L/deltat. The method comprises the steps of collecting high-frequency signals at two ends of a cable by using a Rogowski coil sensor, sampling and recording current signals M (t) (namely a first electric pulse signal) and N (t) (namely a second electric pulse signal) at two ends of the cable, respectively carrying out zero-phase filtering on the M (t) and the N (t), and after zero-phase filtering, no obvious distortion condition exists at the wave head and the wave tail, thereby being beneficial to searching the starting position of the wave head in S4 and obtaining filtered signals M (t) and N (t). Further, the maximum value vmax=max (M) of the current in M (t) is read, the first 500 values of M (t) are compared, and the value Vmmax with the largest amplitude and the value Vmmin with the smallest amplitude in the 500 values are taken. The current difference between the maximum and minimum values is then calculated, as is the current difference vs= (Vmmax-Vmmin). Further, find the X current value from M (t) from front to back, X just satisfies: x > |0.1Vmax+1.2Vs|, finding X, then finding S point from X, the first point satisfies: s < |0.05Vs|. S corresponds to the starting point of the traveling wave, and the corresponding duration is the reflection duration tm1 of the fault traveling wave reflected to the first end for the first time. And the same is true. And obtaining the transmission time tn1 when the fault traveling wave is transmitted from the reflection starting point to the second end. And calculating the time difference delta t1 = tm1-tm2 between the reflection time and the transmission time, wherein the distance from the fault point in the cable to one end of the cable is Xm= (L+delta t1 x v)/2, so that the position of the fault point in the cable is calculated.

After zero-phase filtering is adopted in the technical scheme provided by the invention, no obvious distortion condition exists at the wave head and the wave tail, the starting point of the waveform is calculated, and the position of the fault point is calculated based on the time difference of the two ends. Under the mode of determining the cable fault position, the time difference of the pulse wave reaching the two ends of the cable is not influenced by the dispersion effect in the pulse wave transmission, the positioning accuracy is not reduced due to the pulse wave distortion, the problem that the pulse wave is distorted due to the fact that the frequency response bandwidth of the sensor is narrow can be avoided, and the accuracy of determining the cable fault position is improved.

According to the technical scheme, the preset pulse wave acts on the first end of the cable, the first electric pulse signal corresponding to the first end of the cable and the second electric pulse signal generated at the second end of the cable are collected, the time difference between the first reflection of the pulse wave to the first end and the transmission of the pulse wave from the reflection starting point to the second end is calculated, the time difference can be calculated through the electric pulse signals at the two ends of the cable without detecting the reflection pulse, and then the distance from a fault point to one end of the cable is determined based on the time difference, the length of the cable and the transmission time length from the first end to the second end, the accuracy of determining the fault position of the cable is improved, and the technical effect of guaranteeing safe and stable operation of a power grid is achieved.

Example five

Fig. 7 is a schematic structural diagram of an apparatus for determining a fault location of a cable according to a fifth embodiment of the present invention. As shown in fig. 7, the apparatus includes: a pulse signal acquisition module 710, a time difference determination module 720, and a distance determination module 730.

The pulse signal acquisition module 710 is configured to acquire a first electric pulse signal corresponding to a first end of a cable and a second electric pulse signal generated at a second end of the cable when a preset pulse wave acts on the cable; the first electric pulse signal comprises a forward electric pulse signal generated at the first end of the cable and a reflected pulse signal corresponding to the first electric pulse signal, and the preset pulse wave is transmitted from the first end to the second end; a time difference determining module 720, configured to determine, based on the first electric pulse signal, a reflection duration of the pulse wave reflected to the first end, and determine, based on the second electric pulse signal, a transmission duration of the pulse wave when transmitted from a reflection start point to the second end, so as to determine a time difference based on the reflection duration and the transmission duration; and a distance determining module 730, configured to determine a distance from a fault point in the cable to one end of the cable based on the length of the cable, the time difference, and a conveying duration of the preset pulse wave from the first end to the second end, so as to determine location information of the fault point in the cable based on the distance.

On the basis of the above apparatus, optionally, the time difference determining module 720 includes a pulse signal determining unit to be used, a current set determining unit, and a reflection duration determining unit.

The to-be-used pulse signal determining unit is used for carrying out zero-phase filtering on the first electric pulse signal to obtain a to-be-used pulse signal; wherein the pulse signal to be used comprises a plurality of current values;

the current set determining unit is used for determining a preset number of current values from the pulse signals to be used according to a preset extraction rule to obtain a current set;

the reflection duration determining unit is used for determining the reflection duration based on the pulse signal to be used, the current maximum value in the pulse signal to be used, the current set, the first preset value, the second preset value and the third preset value.

On the basis of the device, optionally, the reflection duration determining unit comprises a current value determining subunit, a current difference value determining subunit and a reflection duration determining subunit.

A current value determination subunit configured to determine a minimum current value and a maximum current value in the current set;

a current difference value determination subunit configured to determine a current difference value based on the minimum current value and the maximum current value;

And the reflection duration determining subunit is used for determining the reflection duration based on the pulse signal to be used, the current maximum value, the current difference value, the first preset value, the second preset value and the third preset value.

On the basis of the device, optionally, the reflection duration determining subunit includes a first reference value determining subunit, a second reference value determining subunit and a reflection duration determining subunit.

A first reference value determining unit for determining a first reference value based on the current maximum value, the current difference value, a first preset value and a second preset value;

a second reference value determining unit for determining a second reference value based on the current difference value and a third preset value;

and the reflection duration determining small unit is used for determining the reflection duration based on the pulse signal to be used, the first reference value and the second reference value.

On the basis of the device, optionally, the reflection duration determining small unit comprises a first time determining micro unit, a second time determining micro unit and a reflection duration determining micro unit.

A first time determining micro unit, configured to find a first time corresponding to a current value greater than the first reference value from the pulse signal to be used according to a time dimension;

A second time determining micro unit, configured to reversely search a current value from a first time in the pulse signal to be used, and determine a second time corresponding to a first current value smaller than the second reference value;

and the reflection duration determining micro unit is used for determining the reflection duration based on the starting time and the second time in the pulse signal to be used.

On the basis of the above apparatus, optionally, the distance determining module 730 includes a transmission speed determining unit and a distance determining unit.

A transmission speed determining unit, configured to determine a transmission speed corresponding to the preset pulse wave based on the length of the cable and the conveying duration;

and a distance determining unit configured to determine the distance based on the length, the time difference, and the transmission speed.

On the basis of the device, optionally, the distance determining unit comprises a first intermediate value determining subunit, a second intermediate value determining subunit and a distance determining subunit.

A first intermediate value determination subunit configured to determine a first intermediate value based on the time difference and the transmission speed;

a second intermediate value determination subunit configured to determine a second intermediate value based on the length and the first intermediate value;

And the distance determining subunit is used for determining the distance based on the second intermediate value and a fourth preset value.

The device for determining the cable fault position provided by the embodiment of the invention can execute the method for determining the cable fault position provided by any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the execution method.

Example six

Fig. 8 is a schematic structural diagram of an electronic device implementing a method for determining a cable fault location according to an embodiment of the present invention. Electronic devices are intended to represent various forms of digital computers, such as laptops, desktops, workstations, personal digital assistants, servers, blade servers, mainframes, and other appropriate computers. Electronic equipment may also represent various forms of mobile devices, such as personal digital processing, cellular telephones, smartphones, wearable devices (e.g., helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions, are meant to be exemplary only, and are not meant to limit implementations of the inventions described and/or claimed herein.

As shown in fig. 8, the electronic device 10 includes at least one processor 11, and a memory, such as a Read Only Memory (ROM) 12, a Random Access Memory (RAM) 13, etc., communicatively connected to the at least one processor 11, in which the memory stores a computer program executable by the at least one processor, and the processor 11 may perform various appropriate actions and processes according to the computer program stored in the Read Only Memory (ROM) 12 or the computer program loaded from the storage unit 18 into the Random Access Memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the electronic device 10 may also be stored. The processor 11, the ROM 12 and the RAM 13 are connected to each other via a bus 14. An input/output (I/O) interface 15 is also connected to bus 14.

Various components in the electronic device 10 are connected to the I/O interface 15, including: an input unit 16 such as a keyboard, a mouse, etc.; an output unit 17 such as various types of displays, speakers, and the like; a storage unit 18 such as a magnetic disk, an optical disk, or the like; and a communication unit 19 such as a network card, modem, wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information/data with other devices via a computer network, such as the internet, and/or various telecommunication networks.

The processor 11 may be a variety of general and/or special purpose processing components having processing and computing capabilities. Some examples of processor 11 include, but are not limited to, a Central Processing Unit (CPU), a Graphics Processing Unit (GPU), various specialized Artificial Intelligence (AI) computing chips, various processors running machine learning model algorithms, digital Signal Processors (DSPs), and any suitable processor, controller, microcontroller, etc. The processor 11 performs the various methods and processes described above, such as a method of determining the location of a cable fault.

In some embodiments, the method of determining the location of a cable fault may be implemented as a computer program tangibly embodied on a computer-readable storage medium, such as storage unit 18. In some embodiments, part or all of the computer program may be loaded and/or installed onto the electronic device 10 via the ROM 12 and/or the communication unit 19. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the method of determining the location of a cable fault described above may be performed. Alternatively, in other embodiments, processor 11 may be configured to perform the method of determining the location of the cable fault in any other suitable manner (e.g., by means of firmware).

Various implementations of the systems and techniques described here above may be implemented in digital electronic circuitry, integrated circuit systems, field Programmable Gate Arrays (FPGAs), application Specific Integrated Circuits (ASICs), application Specific Standard Products (ASSPs), systems On Chip (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and/or combinations thereof. These various embodiments may include: implemented in one or more computer programs, the one or more computer programs may be executed and/or interpreted on a programmable system including at least one programmable processor, which may be a special purpose or general-purpose programmable processor, that may receive data and instructions from, and transmit data and instructions to, a storage system, at least one input device, and at least one output device.

A computer program for carrying out methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the computer programs, when executed by the processor, cause the functions/acts specified in the flowchart and/or block diagram block or blocks to be implemented. The computer program may execute entirely on the machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

In the context of the present invention, a computer-readable storage medium may be a tangible medium that can contain, or store a computer program for use by or in connection with an instruction execution system, apparatus, or device. The computer readable storage medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. Alternatively, the computer readable storage medium may be a machine readable signal medium. More specific examples of a machine-readable storage medium would include an electrical connection based on one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

To provide for interaction with a user, the systems and techniques described here can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to a user; and a keyboard and a pointing device (e.g., a mouse or a trackball) through which a user can provide input to the electronic device. Other kinds of devices may also be used to provide for interaction with a user; for example, feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form, including acoustic input, speech input, or tactile input.

The systems and techniques described here can be implemented in a computing system that includes a background component (e.g., as a data server), or that includes a middleware component (e.g., an application server), or that includes a front-end component (e.g., a user computer having a graphical user interface or a web browser through which a user can interact with an implementation of the systems and techniques described here), or any combination of such background, middleware, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: local Area Networks (LANs), wide Area Networks (WANs), blockchain networks, and the internet.

The computing system may include clients and servers. The client and server are typically remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other. The server can be a cloud server, also called a cloud computing server or a cloud host, and is a host product in a cloud computing service system, so that the defects of high management difficulty and weak service expansibility in the traditional physical hosts and VPS service are overcome.

It should be appreciated that various forms of the flows shown above may be used to reorder, add, or delete steps. For example, the steps described in the present invention may be performed in parallel, sequentially, or in a different order, so long as the desired results of the technical solution of the present invention are achieved, and the present invention is not limited herein.

The above embodiments do not limit the scope of the present invention. It will be apparent to those skilled in the art that various modifications, combinations, sub-combinations and alternatives are possible, depending on design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of the present invention.

Claims

1. A method of determining a location of a cable fault, comprising:

2. The method of claim 1, wherein determining a reflection duration of a pulse wave reflected to the first end based on the first electrical pulse signal comprises:

zero-phase filtering is carried out on the first electric pulse signal to obtain a pulse signal to be used; wherein the pulse signal to be used comprises a plurality of current values;

determining a preset number of current values from the pulse signals to be used according to a preset extraction rule to obtain a current set;

and determining the reflection duration based on the pulse signal to be used, a current maximum value in the pulse signal to be used, the current set, a first preset value, a second preset value and a third preset value.

3. The method of claim 2, wherein the determining the reflection period based on the pulse signal to be used, a current maximum in the pulse signal to be used, the current set, a first preset value, a second preset value, and a third preset value comprises:

determining a minimum current value and a maximum current value in the current set;

determining a current difference value based on the minimum current value and the maximum current value;

and determining the reflection duration based on the pulse signal to be used, the current maximum value, the current difference value, a first preset value, a second preset value and a third preset value.

4. The method of claim 3, wherein the determining the reflection period based on the pulse signal to be used, the current maximum value, the current difference value, a first preset value, a second preset value, and a third preset value comprises:

determining a first reference value based on the current maximum value, the current difference value, a first preset value and a second preset value;

determining a second reference value based on the current difference and a third preset value;

and determining the reflection duration based on the pulse signal to be used, the first reference value and the second reference value.

5. The method of claim 4, wherein the determining the reflection period based on the pulse signal to be used, the first reference value, and the second reference value comprises:

searching a first moment corresponding to a first current value larger than the first reference value from the pulse signal to be used according to the time dimension;

reversely searching a current value from the first time in the pulse signal to be used, and determining a second time corresponding to the first current value smaller than the second reference value;

and determining the reflection duration based on the starting time and the second time in the pulse signal to be used.

6. The method of claim 1, wherein determining the distance from the fault point in the cable to the one end of the cable based on the length of the cable, the time difference, and the length of the transmission of the preset pulse wave from the first end to the second end comprises:

determining a transmission speed corresponding to the preset pulse wave based on the length of the cable and the conveying time length;

the distance is determined based on the length, the time difference, and the transmission speed.

7. The method of claim 6, wherein the determining the distance based on the length, the time difference, and the transmission speed comprises:

determining a first intermediate value based on the time difference and the transmission speed;

determining a second intermediate value based on the length and the first intermediate value;

and determining the distance based on the second intermediate value and a fourth preset value.

8. An apparatus for determining the location of a cable fault, comprising:

9. An electronic device, the electronic device comprising:

at least one processor; and

a memory communicatively coupled to the at least one processor; wherein,,

the memory stores a computer program executable by the at least one processor to enable the at least one processor to perform the method of determining a cable fault location of any one of claims 1-7.

10. A computer readable storage medium storing computer instructions for causing a processor to perform the method of determining a cable fault location of any one of claims 1-7.