CN111413601A - Overhead line partial discharge positioning device and positioning method based on ultrasonic array - Google Patents
Overhead line partial discharge positioning device and positioning method based on ultrasonic array Download PDFInfo
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- CN111413601A CN111413601A CN202010393041.7A CN202010393041A CN111413601A CN 111413601 A CN111413601 A CN 111413601A CN 202010393041 A CN202010393041 A CN 202010393041A CN 111413601 A CN111413601 A CN 111413601A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
- G01R31/1227—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials
- G01R31/1263—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials of solid or fluid materials, e.g. insulation films, bulk material; of semiconductors or LV electronic components or parts; of cable, line or wire insulation
- G01R31/1272—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials of solid or fluid materials, e.g. insulation films, bulk material; of semiconductors or LV electronic components or parts; of cable, line or wire insulation of cable, line or wire insulation, e.g. using partial discharge measurements
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
- G01R31/1209—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing using acoustic measurements
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Abstract
The invention discloses an overhead line partial discharge positioning device and a positioning method based on an ultrasonic array. The device comprises an ultrasonic sensor, an ultrasonic detection conditioning filtering shaping circuit, an analog-to-digital conversion circuit and an ARM processor. When the device works, the ultrasonic array on the ground is arranged facing an overhead line, eight ultrasonic sensors on the ultrasonic array can acquire ultrasonic signals of partial discharge in the overhead line, sixteen times of acquisition at the same position is realized through a multiplexing scheme, the acquired ultrasonic signals are subjected to characteristic frequency selection, filtering and shaping of a subsequent conditioning circuit to obtain the ultrasonic signal intensity of each ultrasonic sensor, and the data information can be subjected to numerical calculation through an ARM (advanced RISC machine) machine so as to analyze and obtain the position of a partial discharge ultrasonic source.
Description
Technical Field
The invention belongs to the technical field of insulation state detection of power equipment, and particularly relates to a partial discharge positioning device and a positioning method applied to 10kV overhead insulated lines and equipment along the lines.
Background
The overhead insulated line is used as the most common power transmission line in a 10kV power distribution network in China, and is widely used in cities and towns and rural areas. Since overhead lines often need to travel through urban roads or forest coverage areas in agricultural fields, abnormal discharge gradually occurs in overhead conductors due to deterioration of wire pole insulators or tree branch friction and the like during long-time operation, and the discharge points can reduce the insulation level of the lines and possibly cause power failure. To solve this problem, ultrasonic detection methods have been proposed to detect partial discharges in overhead insulated lines and have gained acceptance and application in the relevant power enterprises.
The principle of the ultrasonic technology detection line is as follows: partial discharge can occur due to degraded insulation on the line, sound waves are radiated, a line worker holds the handheld ultrasonic measuring instrument to patrol along the line, and the line insulation defect can be found visually once ultrasonic waves are detected. However, the conventional ultrasonic detection method has the following problems: if there is partial discharge hidden danger in the circuit during detection, the detection personnel need make a round trip to detect many times and just can confirm the approximate position of discharge point, and this makes work efficiency lower, and some positions along the line because geographical condition is difficult to be close, and the restriction of measurement angle and measuring distance leads to the degree of difficulty of location to further increase.
With the continuous development of economy and society, power users have a higher pursuit on the power supply reliability of a power distribution network, and higher requirements are put forward on the efficiency and the quality of the operation and maintenance of the overhead line. Although related instruments for ultrasonic detection and positioning exist in the market, the instruments have poor positioning effect in the face of complex terrain, and particularly under the condition that an ultrasonic sensor cannot be directly opposite to a fault point, effective detection is difficult to realize.
Therefore, the accuracy of positioning the ultrasonic sensor is further improved, especially the usability and effectiveness in the face of ground conditions, and the efficiency of positioning the overhead line by partial discharge is improved, which becomes an important issue to be solved urgently when scientific research departments and related enterprises detect the state of the 10kV overhead insulated line.
Disclosure of Invention
The invention provides an overhead line partial discharge positioning device and a positioning method based on an ultrasonic array, which can be used for efficiently and quickly positioning the insulation defects of a 10kV overhead insulated line and equipment along the line, and solves the problem that the partial discharge position cannot be accurately and quickly determined in the current inspection process of a 10kV overhead insulated line.
In order to achieve the above purpose, the overhead line partial discharge positioning device based on the ultrasonic array comprises an ultrasonic sensor array, an ultrasonic shielding case, a filtering amplification circuit, an analog-to-digital conversion circuit and an ARM processor, wherein the ultrasonic sensor array is installed in the ultrasonic shielding case and comprises N groups of ultrasonic sensors, each group of ultrasonic sensors comprises at least two ultrasonic sensors, the signal output end of each ultrasonic sensor is connected with the input end of the filtering amplification circuit, the output end of the filtering amplification circuit is connected with the input end of the analog-to-digital conversion circuit, and the output end of the analog-to-digital conversion circuit is connected with the input end of the ARM processor; the ARM processor is used for calculating the specific position of partial discharge according to data transmitted by the analog-to-digital conversion circuit.
Furthermore, the ultrasonic sensor array is connected with the filtering and amplifying circuit through a multiplexing switch circuit, one group of ultrasonic sensors corresponds to one filtering and amplifying circuit, and the output signal of one ultrasonic sensor in the same group is selected to be transmitted to the filtering and amplifying circuit through the multiplexing switch circuit.
Furthermore, the multiplexing switch circuit adopts ADG736 as a switch chip, a single switch chip comprises two single-pole double-throw controllable analog switches, and the acquisition of 2N sensor signals by the N-channel acquisition circuit is realized by controlling the controllable analog switches through time sequence signals.
Furthermore, the ultrasonic sensors are all positioned on a diagonal line of a top plane of the ultrasonic shielding case and are symmetrically arranged about a midpoint O of the top plane of the ultrasonic shielding case; in the same group of ultrasonic sensors, the horizontal spacing d1 of the ultrasonic sensors is equal to the horizontal distance d2 of the innermost ultrasonic sensor from the midpoint O.
Furthermore, the filtering and amplifying circuit is used for realizing the band-pass filtering and amplifying with the center frequency of 40kHz, the gain of 40dB and the bandwidth of 10 kHz.
Furthermore, the output end of the ARM processor is connected with the communication module and used for interaction between the partial discharge positioning and the computer.
An overhead line partial discharge positioning method based on the partial discharge positioning device comprises the following steps:
and 3, taking one working ultrasonic sensor as a reference working ultrasonic sensor, taking the moment when the working ultrasonic sensor receives the pulse value of the partial discharge signal as a time reference value, and calculating the time difference t between the other working sensors and the reference working ultrasonic sensor for the ith partial discharge pulse1ki，t1ki＝tki-t1iWherein, I ∈ 1-I, k ∈ 2-N, tkiFor the instant t of the ultrasonic sensor k for the ith partial discharge pulse1iThe moment of the working ultrasonic sensor for the ith partial discharge pulse is used as a reference; all time differences t are then calculated1kiIs taken as the statistical time difference t1k(ii) a Spatial coordinate relationship by N working ultrasonic sensorsPropagation velocity of ultrasonic wave in air and statistical time difference t1kCalculating the space position of a single discharge point as (x)1,y1,z1) Completing single positioning;
Further, in step 3, all time differences t are calculated1kiThen, the time difference t is calculated1kiArranged in the order from small to large, and the first 20 percent and the last 20 percent are removed, and the remaining j time differences t are utilized1kiTaking the mean value to obtain the statistical time difference t1k：
Compared with the prior art, the invention has at least the following beneficial technical effects:
the ultrasonic sensor array of the partial discharge positioning device is arranged, a single ultrasonic sensor with low price is effectively utilized, and is matched with a local discharge point to realize accurate positioning, so that an overhead line with potential insulation defects and equipment along the line are quickly positioned, the problem that the existing ultrasonic sensor for high-performance positioning is expensive is solved, the positioning accuracy and the detection effectiveness of the ultrasonic sensor are improved, and the ultrasonic sensor array is suitable for insulation state evaluation of the overhead line and the equipment along the line.
Furthermore, a multiplexing switch circuit is adopted, and signal acquisition of eight sensors by four channels is realized through four paths of single-pole double-throw analog switches. At any time, the same asOnly one of the two ultrasonic sensors in one group works, so that the N groups of ultrasonic sensors can realize 2NIn different combinations, 2 can be realized in a single detection in this wayNAnd (4) secondary effective positioning. And further more data are provided for subsequent algorithm analysis and positioning, the control problem of a multi-ultrasonic sensor system is effectively solved, the problems of redundant acquisition channels and high cost of a multi-channel acquisition system under the condition of no multiplexing are avoided, and the method has higher cost performance.
Furthermore, the ultrasonic amplifying circuit and the filtering circuit are designed according to the characteristics of the sound and electricity signals, and the 120-time pre-amplifying circuit and the band-pass filtering circuit are designed to realize filtering amplification of the center frequency of 40kHz and the gain of 40dB bandwidth of 10kHz, so that interference signals can be effectively filtered, the anti-interference performance of the system is enhanced, and the device has good sensitivity when detecting the ultrasonic signals.
The partial discharge positioning method adopted by the invention utilizes the time difference of the partial discharge ultrasonic signal reaching the sensor and combines the spatial position difference of the sensor to obtain the partial discharge position through mathematical calculation, thereby having good accuracy and reliability.
Further, a maximum of 2 can be performed in a single assayNThe batch effective detection and positioning can remove the positioning result with larger error, screen out the effective positioning result and take mathematical statistics, thereby solving the problem of randomness of single positioning.
Drawings
FIG. 1 is an overall structure diagram of an overhead line partial discharge positioning device based on an ultrasonic array according to the present invention;
FIG. 2 is a schematic diagram of an ultrasonic sensor array for overhead line partial discharge localization in accordance with the present invention;
FIG. 3 is a schematic diagram of a multiplexing switch circuit of the present invention;
FIG. 4 is a schematic diagram of an amplification filter circuit;
FIG. 5 is a schematic diagram of the present invention for field testing;
FIG. 6 is a schematic diagram of sensor time difference extraction when locating partial discharges in an overhead line according to the present invention;
fig. 7 is a flowchart of the algorithm operation of the present invention in locating partial discharges in an overhead line.
In the drawings: 11. the ultrasonic monitoring system comprises an ultrasonic sensor, 12, an ultrasonic shielding case, 13, a filtering and amplifying circuit, 15, an analog-to-digital conversion circuit, 16, an ARM processor, 17, a multiplexing switch, 18, a communication module, 19 and a power supply.
Detailed Description
In order to make the objects and technical solutions of the present invention clearer and easier to understand. The present invention will be described in further detail with reference to the following drawings and examples, wherein the specific examples are provided for illustrative purposes only and are not intended to limit the present invention.
As shown in fig. 1, an overhead line partial discharge positioning device based on an ultrasonic array is a partial discharge positioning device suitable for a 10kV overhead insulated line, and is composed of an ultrasonic sensor 11, an ultrasonic shield 12, a filtering and amplifying circuit 13, an analog-to-digital conversion circuit 15, an ARM processor 16, a multiplexing switch circuit 17, a communication module 18 and a power supply 19.
As shown in fig. 2, the ultrasonic sensor array is composed of four groups of ultrasonic sensors, each group has two sensors, the first group is an ultrasonic sensor a1 and an ultrasonic sensor a2, the second group is an ultrasonic sensor B1 and an ultrasonic sensor B2, the third group is an ultrasonic sensor C1 and an ultrasonic sensor C2, and the fourth group is an ultrasonic sensor D1 and an ultrasonic sensor D2; the ultrasonic sensor a1, the ultrasonic sensor B1, the ultrasonic sensor C1 and the ultrasonic sensor D1 are located at four vertexes of the same square, the ultrasonic sensor a2, the ultrasonic sensor B2, the ultrasonic sensor C2 and the ultrasonic sensor D2 are located at four vertexes of another square, and the two squares and the ultrasonic shield 12 are concentrically arranged. The same set of ultrasound sensors is located in the same corner of the rectangular ultrasound shield 12. All the ultrasonic sensors have the same performance, and the ultrasonic sensor has the advantages of light weight, low price and capability of meeting the requirement on detection precision. In a single positioning, four groups of sensors are respectively extracted one by one, and an effective detection batch is formed. Four sets of eight sensors can constitute 16 effective detection batches.
The side length of the square ultrasonic shielding case 12 is 52 cm, all the ultrasonic sensors are positioned on the diagonal line of the overlooking plane of the square shielding case 12, and the horizontal distance d between the sensor on the outer square and the sensor on the inner square1Equal to the horizontal distance d between the inner side sensor and the center of the ultrasonic shielding case 122All are 10 cm. The reason for this distribution of the sensors is to facilitate the subsequent localization and calculation of the partial discharges, which is more evident when multiple test batches are used for localization. According to the frequency spectrum characteristic of the partial discharge signal under the overhead insulation, the ultrasonic sensor with the center frequency of 40kHz is selected, and the conversion from the ultrasonic signal to the electric signal is realized.
The ultrasound shield 12 has three main functions: 1) the mounting base is used as an ultrasonic sensor, so that the sensitivity of ultrasonic detection is improved; 2) the sensitivity of each ultrasonic sensor at the mounted position is ensured to be the same, and no error is brought to subsequent analysis; 3) the interference of other ultrasonic signals along the overhead line is shielded, and the influence of bottom noise caused by the working of the device is reduced.
The amplifying circuit in the filtering amplifying circuit 13 is used as a pre-amplifying circuit to amplify the ultrasonic signal by 120 times, so that the ultrasonic signal is better used for subsequent processing.
The filter circuit in the filter amplifying circuit 13 is composed of a band-pass filter circuit and a peak value holder, and the main function of the filter amplifying circuit is to filter interference of communication signals and other signals during positioning, and the band-pass filter circuit and the amplifying circuit can realize band-pass filter amplification with the central frequency of 40kHz and the gain of 40dB and the bandwidth of 10 kHz. The peak value retainer is used for realizing frequency reduction sampling, the acquisition card which ensures the sampling rate of 20MS/s can effectively acquire partial discharge, and the product cost is reduced.
The analog-to-digital conversion circuit 15 is composed of a four-channel data acquisition card with a sampling rate of 20MS/s and a sampling bit number of 16 bits, and is used for respectively converting signals of four groups of ultrasonic sensors in a single detection batch.
The ARM processor 16 is an embedded microprocessor, and its main functions are to implement control functions such as multiplexing in the whole positioning process, and processing and transmission of data, and it has the advantages of high execution efficiency and low cost.
The multiplexing switch circuit 17 is a four-way single-pole double-throw analog switch, can realize signal acquisition of eight ultrasonic sensors through four acquisition channels, can more flexibly control the whole positioning system by using the multiplexing switch, and also reduces the cost of the acquisition system.
The communication module 18 mainly comprises a signal receiving module and a signal transmitting module, and has the main function of realizing the communication of control information and data information of the partial discharge positioning device and a portable computer (staff).
The power supply 19 is composed of a lithium battery and a DC-DC voltage stabilizing module and is used for supplying power to the whole ultrasonic positioning device.
Referring to fig. 3, the front end of the multiplexing switch circuit is connected with the outputs of 8 ultrasonic sensors, the rear end of the multiplexing switch circuit is connected with 4 ultrasonic amplifying and filtering circuits, and the multiplexing switch circuit is connected with the ARM processor and is conducted by the control signal of the ARM processor. The multiplexing switch circuit selects two ADGs 736 as switch chips to realize the conduction of the signal side and the control processing side. A single chip comprises two single-pole double-throw controllable analog switches, so that the four analog switches can be controlled by time sequence signals to realize the acquisition of eight sensor signals by a four-way acquisition circuit, thereby achieving 2416 valid fixes. The number of subsequent amplifying filter circuits and acquisition circuits can be reduced through the multiplexing mode, and the complexity of subsequent hardware circuits is reduced while the positioning accuracy is improved through multi-batch positioning. As shown in the figure, if a multiplexing circuit is not used, the system needs to increase the number of the filtering and amplifying circuits by one time to achieve the same performance, so that the circuit greatly reduces the system cost and meets the economic requirement.
As shown in fig. 4, the single ultrasonic amplifying and filtering circuit is one of the four ultrasonic amplifying and filtering circuits at the back end of fig. 3, and the other three circuits are consistent with the circuit in terms of original components and parameters. The front end of the ultrasonic transducer is connected with the output side of the multiplexing switch circuit, the rear end of the ultrasonic transducer is connected with the analog-to-digital conversion circuit, and the ultrasonic transducer amplifies and filters the ultrasonic signals transmitted from the multiplexing switch circuit and transmits the signals to the analog-to-digital conversion circuit for conversion. Is singleThe ultrasonic amplification and filtering circuit selects two ADA4528 chips as core chips, the offset voltage is as low as 2.5 mu V, the noise is as low as 5.6nV/Hz, the common mode rejection ratio is as high as 135dB, and the effective amplification of small signals in an ultrasonic frequency band is well realized. The parameter configuration of the circuit is given by fig. 4, where R11、R21Is 12.8 k.OMEGA.R12、R22Is 115k omega, R13、R23Is 980 omega, R14、R24Is 12.8 k.OMEGA.R15、R25Is 115k omega, R16、R26Is 980 omega, C11、C21、C12、C22Is 360pF, C13、C23、C14、C24Is 450 pF. In order to realize larger amplification factor, the amplifying and filtering circuit selects two pieces of ADA4528 to be connected in series, and corresponding circuit elements and parameters are the same. The monolithic ADA4528 chip includes two amplifier circuits, the first of which is represented by R in the left chip of the figure11，R12，R13The second amplifying circuit is composed of R14，R15，R16And composition, and amplification is realized through the proportional relation between the resistors. For the filter circuit, in the first amplifying circuit, the first amplifying circuit is composed of R12And its parallel capacitor C11And a series capacitor C12Forming a filter circuit; in the second amplifying circuit, the first amplifying circuit is composed of R15And its parallel capacitor C13And a series capacitor C14Forming a filter circuit; the filter circuit can well realize the filtering effect through parameter matching.
In the circuit connection system, a single amplifying circuit is taken as an example, the resistor R11The first end is the input side of the signal to be amplified and is connected with the output of the multiplexing switch, and the second end is connected with the series capacitor C12Parallel capacitor C11A pull-down resistor R13Are connected with each other; series capacitor C12The second terminal is connected to the resistor R12And the input port of the amplifier. The amplifier signal is output from OA and connected to a parallel capacitor C11And a resistance R12Resistance R14Connected to the input of the second amplifier. The second amplifying circuit is similar to the first amplifying circuit, and the second amplifying circuit is used for amplifying the signal at the OB output port and the resistorR21And the amplifier circuit is connected to transmit the signal to the next chip. In this way, the serial amplification of four amplification circuits of two chips is finally realized. Through practical tests, the amplifying and filtering circuit can realize filtering amplification with the center frequency of 40kHz, the passband of 35kHz-45kHz and the gain of 40dB, thereby well solving the problem of obvious attenuation of high-frequency ultrasonic of overhead line ultrasonic detection and inhibiting the interference of the audible frequency band of 20kHz human ears.
As shown in FIG. 5, when the device is used for field test, if there is insulation defect at a certain position in the line, partial discharge is generated, and the distances from the position to two ultrasonic sensors of the ultrasonic sensor array are L respectively1、L2. Due to the selection function of the multiplexing switch, the four ultrasonic sensors work simultaneously, the four sensors correspond to four different distances from the position, the propagation speed of ultrasonic waves in the air is unchanged, so that the time of the ultrasonic signals reaching the four sensors is different, the distance difference is reflected by the time difference, and the positioning effect is realized.
The working principle of the partial discharge positioning device of the overhead insulated line is as follows: the device during operation, the ultrasonic array face that is in ground is arranged towards the overhead line, eight ultrasonic sensor all can gather the ultrasonic signal of partial discharge in the overhead line, and through data acquisition device's multiplexing scheme, can realize that same position carries out sixteen times and gather, four ways ultrasonic signal are gathered to the single time, the ultrasonic signal who gathers is through follow-up ultrasonic amplification and filter circuit's amplification, filtering, and then obtain the ultrasonic signal intensity of individual ultrasonic sensor department, these data message can carry out numerical calculation through ARM, thereby the analysis reachs the position of partial discharge ultrasonic source.
As shown in fig. 5, in order to realize the positioning function, the time difference of the partial discharge pulses received by different ultrasonic sensors is calculated. Because the device uses a multiplex switch, only one sensor in the same group of sensors in a single detection batch of the ultrasonic sensor array works, and the sensor in the first group is taken as a time reference value, thenThere are three independent time differences that can be calculated, i.e. the time difference t between the sensors of the second group and the sensors of the first group12Time difference t of the sensors of the third group and the sensors of the first group13Time difference t between the sensors of the fourth group and the sensors of the first group14(ii) a The time difference t between the second group of sensors and the first group of sensors will be described by taking fig. 3 as an example12And (3) calculating:
as shown in FIG. 5, when the first ultrasonic sensor and the second ultrasonic sensor face the same partial discharge source, due to the difference of their own positions, the pulse values of the same discharge signal received by the first ultrasonic sensor and the second ultrasonic sensor have a time difference t12Wherein the time difference t for the ith partial discharge pulse12iThe method comprises the following steps:
t12i＝tultrasound ii-tUltrasonic I(1)
Wherein, tUltrasonic IMoment t of collecting ith partial discharge pulse for ultrasonic sensorUltrasound iiAnd I ∈ 1-I is the time when the ith partial discharge pulse is acquired by the second ultrasonic sensor.
Therefore, the time difference values corresponding to the I discharge pulses (I is 11 in the figure) collected in the same batch can be obtained. The differences are arranged from small to large, and the first 20% and the last 20% are removed to reduce the influence of random errors. Using the remaining j difference values, averaging to obtain the statistical time difference t12：
T can be obtained by the same method13And t14Let the spatial coordinates of the four sensors be (x) respectively1,y1,z1)、(x2,y2,z2)、(x3,y3,z3)、(x4,y4,z4) The sensor plane is defined as an xOy plane, one sensor position is located at the origin of coordinates, and the coordinates can be transcribed as follows according to the spatial position relation: (0, 0, 0), (x)2,y2,0)、(x3,y3,0)、(x4,y4,0). Assuming that the partial discharge point spatial position is (x, y, z), the following equation can be followed:
wherein v issThe propagation speed of the ultrasonic wave in the air is 340 m/s; the above formula comprises three equations and three unknowns, and the discharge point spatial position is (x, y, z) which is easy to solve through digital calculation.
The single detection positioning of the partial discharge is completed through the process, and the positioning result is written as (x)1,y1,z1) And the eight ultrasonic sensors of the ultrasonic array can realize 16 times of detection and positioning through multiplexing, so that a spatial position average value point (x) can be obtainedm,ym,zm) I.e. by
And then calculating the Euclidean distance between each positioning point and the average value point, and removing the 6 positioning results with the maximum Euclidean distance. Taking the spatial position average value by the method of the formula (4) in the remaining 10 results, and obtaining the positioning result (x) with smaller errorn,yn,zn). Sixteen times of acquisition at the same position are realized through multiplexing, and the problems of signal interference and data errors faced by single positioning can be effectively avoided.
As shown in fig. 6, a positioning method of the overhead line partial discharge positioning device based on the ultrasonic array includes the following steps:
And 2, the ARM processor controls multiplexing to select four outer sensors in the four groups of sensors as an initial working sequence to acquire a partial discharge ultrasonic signal, if the detection value of any one sensor exceeds the set partial discharge detection threshold value in the step 1, the step 3 is skipped, and otherwise, information of 'no partial discharge' is transmitted to the ARM processor (namely, a control end).
And 3, starting positioning, starting to operate from the initial working sequence selected in the step 2, sequentially obtaining the time difference of a single pulse through the formula (1) and the formula (2) and counting the time difference to obtain a positioning single-detection positioning result through the formula (3), wherein the working sequence refers to four sensor combinations which are selected from 8 sensors and work simultaneously.
and 5, calculating the mathematical mean value of the spatial position of the M discharge points obtained in the step 4, calculating the Euclidean distance between each positioning position and the mean value point, screening out positioning results with larger errors, and calculating the statistical value of the positioning results in the rest results by the method of the formula (4).
And 6, transmitting the statistical value of the positioning result obtained in the step 5 to a control end for viewing, and finally realizing the high-precision positioning of the partial discharge in the overhead line through the ultrasonic array.
The invention has stronger anti-interference capability, avoids a complex and expensive signal acquisition and processing system by a multiplexing mode, has the advantages of small volume, easy carrying and convenient operation, is very suitable for the field use of the insulation evaluation of overhead lines and equipment along the line, and has greater engineering practical value.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the present invention in any way, and it will be apparent to those skilled in the art that the above description of the present invention can be applied to various modifications, equivalent variations or modifications without departing from the spirit and scope of the present invention.
Claims (8)
1. An aerial wire partial discharge positioning device based on an ultrasonic array is characterized by comprising an ultrasonic sensor array, an ultrasonic shielding case (12), a filtering amplification circuit (13), an analog-to-digital conversion circuit (15) and an ARM processor (16), wherein the ultrasonic sensor array is installed in the ultrasonic shielding case (12), the ultrasonic sensor array comprises N groups of ultrasonic sensors, each group of ultrasonic sensors comprises at least two ultrasonic sensors (11), the signal output end of each ultrasonic sensor (11) is connected with the input end of the filtering amplification circuit (13), the output end of the filtering amplification circuit (13) is connected with the input end of the analog-to-digital conversion circuit (15), and the output end of the analog-to-digital conversion circuit (15) is connected with the input end of the ARM processor (16); the ARM processor (16) is used for calculating the position of partial discharge according to data transmitted by the analog-to-digital conversion circuit (15).
2. The overhead line partial discharge positioning device based on the ultrasonic array is characterized in that the ultrasonic sensor array is connected with the filter amplification circuit (13) through a multiplexing switch circuit (17), one group of ultrasonic sensors corresponds to one filter amplification circuit (13), and the output signal of one ultrasonic sensor in the same group is selected through the multiplexing switch circuit (17) and transmitted to the filter amplification circuit (13).
3. The overhead line partial discharge positioning device based on the ultrasonic array as claimed in claim 2, wherein the multiplexing switch circuit (17) adopts the ADG736 as a switch chip, a single switch chip comprises two single-pole double-throw controllable analog switches, and the acquisition of 2N sensor signals by the N-way acquisition circuit is realized through the control of the controllable analog switches by timing signals.
4. The overhead line partial discharge positioning device based on the ultrasonic array is characterized in that the ultrasonic sensors (11) are positioned on the diagonal line of the top plane of the ultrasonic shielding case (12) and are symmetrically arranged about the midpoint O of the top plane of the ultrasonic shielding case (12); in the same group of ultrasonic sensors, the horizontal distance d1 between the ultrasonic sensors (11) is equal to the horizontal distance d2 between the innermost ultrasonic sensor (11) and the midpoint O.
5. The overhead line partial discharge positioning device based on the ultrasonic array as claimed in claim 1, wherein the filter amplification circuit (13) is used for realizing bandpass filter amplification with a center frequency of 40kHz, a gain of 40dB and a bandwidth of 10 kHz.
6. The overhead line partial discharge positioning device based on the ultrasonic array as claimed in claim 1, wherein the output end of the ARM processor (16) is connected with a communication module (18) for the partial discharge positioning and computer interaction.
7. An overhead line partial discharge positioning method based on the partial discharge positioning device of claim 1, characterized by comprising the steps of:
step 1, setting a partial discharge detection threshold, and acquiring pulse number I and preset positioning times M of an ultrasonic sensor in single detection positioning;
step 2, selecting 1 sensor in each group of ultrasonic sensors as an initial working ultrasonic sensor to obtain a partial discharge ultrasonic signal, if the detection value of any one sensor exceeds the set partial discharge detection threshold value in the step 1, jumping to the step 3, otherwise, transmitting a signal without partial discharge to an ARM processor (16);
and 3, taking one working ultrasonic sensor as a reference working ultrasonic sensor, taking the moment when the working ultrasonic sensor receives the pulse value of the partial discharge signal as a time reference value, and calculating the time difference t between the other working sensors and the reference working ultrasonic sensor for the ith partial discharge pulse1ki，t1ki＝tki-t1iWherein, I ∈ 1-I, k ∈ 2-N, tkiFor the instant t of the ultrasonic sensor k for the ith partial discharge pulse1iThe moment of the working ultrasonic sensor for the ith partial discharge pulse is used as a reference; all time differences t are then calculated1kiOfMean value, said mean value being recorded as the statistical time difference t1k(ii) a Through the space coordinate relation of N working ultrasonic sensors, the propagation speed of ultrasonic waves in the air and the statistical time difference t1kCalculating the space position of a single discharge point as (x)1,y1,z1) Completing single positioning;
step 4, the ARM processor (16) controls the four-way multiplexing switch to act and replace the working sensor, so that multiple times of positioning of a single discharge point is realized until M times of positioning are carried out, and M discharge point space positions are obtained;
step 5, calculating the mathematical mean value of the M discharge point space positions obtained in the step 4, calculating the Euclidean distance between each positioning position and the mean value point, removing the discharge point space position with the largest Euclidean distance, and calculating the statistical value (x) of the rest M-l discharge point space positionsn,yn,zn) The statistical value (x)n,yn,zn) The coordinates of the partial discharge positioning points are obtained.
8. The method for locating the partial discharge of the overhead line based on the ultrasonic array as claimed in claim 7, wherein in the step 3, all the time differences t are calculated1kiThen, the time difference t is calculated1kiArranged in the order from small to large, and the first 20 percent and the last 20 percent are removed, and the remaining j time differences t are utilized1kiTaking the mean value to obtain the statistical time difference t1k：
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112083297A (en) * | 2020-08-20 | 2020-12-15 | 西安交通大学 | Sound pressure-based anti-interference transformer partial discharge positioning method and device |
| CN112595934A (en) * | 2020-10-14 | 2021-04-02 | 浙江大有实业有限公司杭州科技发展分公司 | Method and device for measuring partial discharge signal intensity of high-voltage cable |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1834669A (en) * | 2006-04-19 | 2006-09-20 | 重庆大学 | On-line detecting and positioning device for local discharging of electrical insulated combined electrical appliance, and positioning method thereof |
| CN101493438A (en) * | 2009-02-18 | 2009-07-29 | 宁波工程学院 | Phased array ultrasonic detection, data acquisition and process device |
| CN205176139U (en) * | 2015-09-24 | 2016-04-20 | 武汉三新电力设备制造有限公司 | Wireless voice insulator resistance tester |
| CN206258554U (en) * | 2016-11-30 | 2017-06-16 | 国家电网公司 | Buchholz relay flow velocity setting device |
| CN109917249A (en) * | 2019-04-03 | 2019-06-21 | 国网陕西省电力公司电力科学研究院 | A kind of shelf depreciation positioning device and method for the patrol unmanned machine of power equipment |
| CN109917258A (en) * | 2019-04-27 | 2019-06-21 | 西南交通大学 | High-power transformer shelf depreciation position finding and detection method |
| CN110208667A (en) * | 2019-07-10 | 2019-09-06 | 江苏利得智能监测科技有限公司 | GIS equipment partial discharge localization method based on time switch technology |
| CN110609072A (en) * | 2019-10-17 | 2019-12-24 | 南京工业大学 | Weak signal detection circuit of Prussian blue membrane bioelectrode |
| CN110618238A (en) * | 2019-09-29 | 2019-12-27 | 欧勒姆电气(珠海)有限公司 | Self-adaptive driving circuit of gas sensor |
-
2020
- 2020-05-11 CN CN202010393041.7A patent/CN111413601A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1834669A (en) * | 2006-04-19 | 2006-09-20 | 重庆大学 | On-line detecting and positioning device for local discharging of electrical insulated combined electrical appliance, and positioning method thereof |
| CN101493438A (en) * | 2009-02-18 | 2009-07-29 | 宁波工程学院 | Phased array ultrasonic detection, data acquisition and process device |
| CN205176139U (en) * | 2015-09-24 | 2016-04-20 | 武汉三新电力设备制造有限公司 | Wireless voice insulator resistance tester |
| CN206258554U (en) * | 2016-11-30 | 2017-06-16 | 国家电网公司 | Buchholz relay flow velocity setting device |
| CN109917249A (en) * | 2019-04-03 | 2019-06-21 | 国网陕西省电力公司电力科学研究院 | A kind of shelf depreciation positioning device and method for the patrol unmanned machine of power equipment |
| CN109917258A (en) * | 2019-04-27 | 2019-06-21 | 西南交通大学 | High-power transformer shelf depreciation position finding and detection method |
| CN110208667A (en) * | 2019-07-10 | 2019-09-06 | 江苏利得智能监测科技有限公司 | GIS equipment partial discharge localization method based on time switch technology |
| CN110618238A (en) * | 2019-09-29 | 2019-12-27 | 欧勒姆电气(珠海)有限公司 | Self-adaptive driving circuit of gas sensor |
| CN110609072A (en) * | 2019-10-17 | 2019-12-24 | 南京工业大学 | Weak signal detection circuit of Prussian blue membrane bioelectrode |
Non-Patent Citations (1)
| Title |
|---|
| 杨扬等: "《变压器局部放电超声定位中的自适应优化算法》", 《测控技术》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112083297A (en) * | 2020-08-20 | 2020-12-15 | 西安交通大学 | Sound pressure-based anti-interference transformer partial discharge positioning method and device |
| CN112083297B (en) * | 2020-08-20 | 2021-08-13 | 西安交通大学 | Sound pressure-based anti-interference transformer partial discharge positioning method and device |
| CN112595934A (en) * | 2020-10-14 | 2021-04-02 | 浙江大有实业有限公司杭州科技发展分公司 | Method and device for measuring partial discharge signal intensity of high-voltage cable |
| CN112595934B (en) * | 2020-10-14 | 2024-05-17 | 浙江大有实业有限公司杭州科技发展分公司 | Method and device for measuring intensity of partial discharge signal of high-voltage cable |
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