CN111579945A - Integrated switch cabinet partial discharge intelligent sensor and information fusion state evaluation method thereof - Google Patents

Integrated switch cabinet partial discharge intelligent sensor and information fusion state evaluation method thereof Download PDF

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CN111579945A
CN111579945A CN202010439619.8A CN202010439619A CN111579945A CN 111579945 A CN111579945 A CN 111579945A CN 202010439619 A CN202010439619 A CN 202010439619A CN 111579945 A CN111579945 A CN 111579945A
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黄成军
郭灿新
黄志方
刘丹丹
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Huacheng Electrical Technology Co ltd
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    • G—PHYSICS
    • G01—MEASURING; TESTING
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    • 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
    • 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
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
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Abstract

The invention discloses an integrated switch cabinet local discharge intelligent sensor which comprises a signal acquisition module, a conditioning module, a signal generation module, an MCU (microprogrammed control unit) module, a communication module and a power supply module which are integrated together, wherein the local discharge intelligent sensor is magnetically attracted on the outer surface of a switch cabinet; the signal acquisition module consists of an ultrasonic sensor, a geoelectric wave sensor and a temperature sensor; the integrated switch cabinet local discharge intelligent sensor integrates acquisition, signal processing, communication and power supply into one physical structure, has a sensor self-diagnosis function, and realizes the intellectualization, the miniaturization, the integration and the non-humanization of the sensor. The invention also discloses an information fusion state evaluation method of the integrated switch cabinet local discharge intelligent sensor, which establishes a comprehensive state evaluation system of the switch cabinet, fuses the test results of the ultrasonic waves, the earth electric waves and the cabinet body temperature, and judges the running state of the switch cabinet.

Description

Integrated switch cabinet partial discharge intelligent sensor and information fusion state evaluation method thereof
Technical Field
The invention relates to an integrated switch cabinet partial discharge intelligent sensor and an information fusion state evaluation method thereof, and belongs to the technical field of switch cabinet detection.
Background
The switch cabinet is an important component unit in a power grid system and has double functions of controlling and protecting electrical equipment. In long-term operation, insulation faults of the switch cabinet bring hidden dangers to reliable operation of a power grid, and direct damage is damage to circuits and equipment controlled and protected by the switch cabinet and electric quantity loss; the indirect harm is large-area power failure of users, which causes huge economic loss, and therefore, the insulation state of the switch cabinet needs to be closely concerned.
The most common faults of the switch cabinet are partial discharge and overheating, the insulation state of electrical equipment can be effectively judged by partial discharge detection, and in view of the structural characteristics of the switch cabinet, optical, chemical and current traveling waves are difficult to be used in non-embedded partial discharge detection, the currently commonly used switch cabinet partial discharge detection method mainly takes an electromagnetic method and an ultrasonic method as main methods, and can be used as an auxiliary method by combining a thermal scanning technology for serious discharge phenomena. Through simulation experiments, the ground electric wave method has good detection effects on point discharge, corona discharge and internal discharge of the insulator, but is not sensitive to surface discharge; the ultrasonic wave has good detection effect on creeping discharge and insulator surface discharge, but is not sensitive to the internal discharge of the insulator. Therefore, when the insulation defect of the switch cabinet is detected, the earth electric wave method is often used in combination with the ultrasonic wave method, and the temperature measurement is combined to be used as an auxiliary means, so that the partial discharge condition can be detected more comprehensively, and more reliable data can be provided for the diagnosis of the insulation fault of the switch cabinet.
The sensor technology is evolving towards the direction of intellectualization, miniaturization, integration and passivity, the existing switch cabinet partial discharge sensor has single function, is mainly responsible for collecting state quantity information and does not have the capability of data analysis and state evaluation; the detection technology is single, and various sensors need to be replaced when combined detection is carried out by various methods, so that the workload of detection personnel is increased, and the working process is complicated; the multi-source data fusion analysis comprehensive evaluation system is imperfect, the correlation of each state quantity is neglected, the information fusion is poor, and the state of the switch cabinet cannot be truly reflected; the detection reliability is not high, the sensor lacks a self-diagnosis function, and the accuracy of the detection data cannot be ensured; the integrated level is low, the structure is complicated, each functional module of sensor components of a whole that can function independently designs, adopts the cable to connect between the module, has increased the test degree of difficulty.
Disclosure of Invention
The invention aims to overcome the defects of the prior art, and provides an integrated switch cabinet local discharge intelligent sensor which integrates various detection technologies, can judge the working state of the sensor and locally evaluate the running state of a switch cabinet, thereby improving the functional diversity and the working reliability of the sensor; an extensible communication mode and a power supply mode are adopted, so that the compatibility of the sensor is improved; the installation is convenient, the work flow is simple, and the work efficiency is improved.
The invention also aims to provide an information fusion state evaluation method of the integrated switch cabinet local discharge intelligent sensor, which adopts three detection technologies of ultrasonic waves, transient ground voltage and cabinet body temperature, fuses test results of three state quantities, establishes a comprehensive grading model and comprehensively judges the running state of the switch cabinet.
One technical scheme for achieving the purpose is as follows: the utility model provides an integral type cubical switchboard partial discharge intelligent sensor, includes integrated signal acquisition module, conditioning module, signal generation module, MCU module, communication module and power module together, partial discharge intelligent sensor magnetism is inhaled at the surface of cubical switchboard, wherein:
the signal acquisition module consists of an ultrasonic sensor, a ground electric wave sensor and a temperature sensor, and the ultrasonic sensor acquires ultrasonic signals generated when the switch cabinet is partially discharged and sends the ultrasonic signals to the conditioning module; the ground electric wave sensor collects transient ground electric wave signals generated when the switch cabinet discharges locally and sends the transient ground electric wave signals to the conditioning module; the temperature sensor is used for acquiring the surface temperature of the cabinet body during partial discharge of the switch cabinet and sending the surface temperature of the cabinet body to the conditioning module;
the conditioning module is connected with the signal acquisition module, and is used for respectively converting the received ultrasonic signals and transient earth electric wave signals into partial discharge digital signals and sending the converted partial discharge digital signals to the MCU module, and the conditioning module performs self-checking judgment;
the signal generating module is connected with the conditioning module and is used for generating ultrasonic analog signals and earth electric wave analog signals and providing standard analog signal sources for equipment self-inspection;
the MCU module is respectively connected with the conditioning module and the signal generating module and is used for processing, analyzing and receiving the partial discharge digital signal, evaluating and judging the running state of the switch cabinet and controlling the signal generating module to send an analog signal;
the communication module is connected with the MCU module, transmits the data and the self-checking result of the MCU module to an external data collecting node in a wired and wireless mode, and receives a self-checking command sent by the external data collecting node;
and the power supply module is used for supplying power to the conditioning module, the signal generation module, the MCU module and the communication module.
The above-mentioned integral type cubical switchboard partial discharge intelligent sensor, wherein, the conditioning module includes amplifying unit, filtering unit, detection unit, analog-to-digital conversion unit and self-checking judgement unit, amplifying unit, filtering unit, detection unit, analog-to-digital conversion unit and self-checking judgement unit link to each other in proper order, analog-to-digital conversion unit with amplifying unit links to each other, wherein:
the amplification unit is connected with the signal acquisition module and is used for amplifying the ultrasonic signals and the transient earth electric wave signals output by the signal acquisition module; the amplifying unit transmits the amplified ultrasonic signals to the filtering unit, and the amplifying unit transmits the amplified transient ground electric wave signals to the analog-to-digital conversion unit;
the filtering unit is used for filtering the ultrasonic signal output by the amplifying unit;
the wave detection unit is used for carrying out wave detection processing on the ultrasonic wave signal output by the filtering unit;
the analog-to-digital conversion unit is used for respectively converting the ultrasonic wave signal output by the detection unit and the earth electric wave signal output by the amplification unit into digital signals;
and the self-checking judgment unit judges whether the partial discharge intelligent sensor works normally or not by comparing the self-checking result output by the analog-to-digital conversion unit with a preset threshold value.
In the above intelligent sensor for partial discharge of integrated switch cabinet,
the amplification unit comprises an ultrasonic signal amplification circuit and a ground electric wave signal amplification circuit, and the ultrasonic signal amplification circuit is used for amplifying the ultrasonic signal from the ultrasonic sensor; the earth electric wave signal amplifying circuit is used for carrying out nonlinear amplification on the transient earth electric wave signal from the earth electric wave sensor;
the analog-to-digital conversion unit comprises an ultrasonic signal analog-to-digital conversion circuit and a ground electric wave analog-to-digital conversion circuit, the ultrasonic signal analog-to-digital conversion circuit is used for converting the ultrasonic analog signals from the signal generation module into digital signals, and the ground electric wave signal analog-to-digital conversion circuit is used for converting the ground electric wave analog signals from the signal generation module into digital signals.
The above-mentioned integral type cubical switchboard partial discharge intelligent sensor, wherein, the signal generation module includes signal generation control unit, supersound analog signal generation unit and ground voltage analog signal generation unit respectively with signal generation control unit links to each other, wherein:
the signal generation control unit is used for controlling the ultrasonic analog signal generation unit and the ground voltage analog signal generation unit to send out corresponding analog signals;
the ultrasonic analog signal generating unit is used for generating standard ultrasonic analog signals with fixed characteristics;
the ground voltage analog signal generating unit is used for generating a standard ground voltage analog signal with fixed characteristics.
The above-mentioned integral type cubical switchboard partial discharge intelligent sensor, wherein, the signal takes place the control unit and is in send control signal when the electricity starts on the partial discharge intelligent sensor, perhaps regularly sends control signal through setting up the time interval, perhaps sends control signal through receiving the self-checking request that external equipment sent, the signal takes place the control unit and passes through control signal control supersound analog signal generating unit and ground voltage analog signal generating unit send corresponding analog signal.
The utility model provides an foretell integral type cubical switchboard partial discharge intelligent sensor, wherein, communication module adopts wired and wireless two kinds of communication mode, communication module is used for transmitting ultrasonic wave, transient state ground electric wave, cabinet body surface temperature's digital signal and self-checking result, communication module possesses the function that receives partial discharge intelligent sensor and starts the self-checking order to will start the self-checking order and send to the MCU module.
The above-mentioned integral type cubical switchboard partial discharge intelligent sensor, wherein, be provided with the lithium cell in the power module, power module reserves external power source interface.
The invention also provides an information fusion state evaluation method of the integrated switch cabinet local discharge intelligent sensor, which comprises the following steps:
s1, respectively calculating the fraction of each detection item according to three detection results of the geoelectric wave sensor, the ultrasonic sensor and the temperature sensor, wherein the formula is as follows:
Figure BDA0002502166840000041
wherein M isiScoring the ith detection item, wherein the detection items are geoelectric waves, ultrasonic waves and temperature respectively; when M isiWhen less than 0, let Mi0; when M isiWhen greater than 1, let Mi＝1；
Figure BDA0002502166840000042
The warning value of the ith detection item is 1.3 times of attention value, and the earth electric waveThe attention value of the signal is 20dB of earth electric wave, the attention value of the ultrasonic signal is 8dB, the attention value of the temperature is T +20 ℃, wherein T is the ambient temperature;
Figure BDA0002502166840000043
the environment value of the ith detection item of the tested device is obtained;
Figure BDA0002502166840000044
is the measured value of the ith detection item; kFThe family defect coefficient is 0.95 for the part with family defect, and the family defect coefficient is 1 for the part without family defect; kTIs a life factor, KT(100-years of operation × 0.3.3)/100;
s2, calculating the weight coefficient of each detection item according to the score of each detection item, wherein the formula is as follows:
Figure BDA0002502166840000051
wherein, WiThe weight coefficient of the ith detection item;
Figure BDA0002502166840000052
the constant weight coefficients of the ith detection item are 0.15, 0.35 and 0.5; miThe score of the ith test item; j is the number of detection items;
Figure BDA0002502166840000053
a constant weight coefficient for the jth detection term; mjThe score of the jth detection item;
s3, calculating the comprehensive state score according to the scores of the detection items and the weight coefficient, wherein the formula is as follows:
Figure BDA0002502166840000054
wherein x is the total score after the information of the switch cabinet is fused; i is the number of detection items; miFor the ith test itemGrading; wiThe weight coefficient of the ith detection item;
s4, solving a membership matrix according to the comprehensive score and a membership function, wherein the membership function formula is as follows:
health status:
Figure BDA0002502166840000055
and (3) normal state:
Figure BDA0002502166840000056
abnormal state:
Figure BDA0002502166840000057
early warning state:
Figure BDA0002502166840000058
and (4) alarm state:
Figure BDA0002502166840000059
membership matrix: f ═ F1(x)，f2(x)，f3(x)，f4(x)，f5(x)}；
S5, evaluating the equipment state grade according to the membership matrix, and selecting the grade corresponding to the maximum membership as the comprehensive state grade of the switch cabinet by adopting the maximum membership principle, wherein f1(x)、f2(x)、f3(x)、f4(x)、f5(x) The one-to-one correspondence levels are health, normal, abnormal, early warning and alarm.
Compared with the prior art, the integrated switch cabinet local discharge intelligent sensor and the technical scheme of the information fusion state evaluation method thereof have the following beneficial effects:
(1) the ultrasonic signal, the earth electric wave signal and the temperature signal generated by partial discharge can be detected simultaneously, the three detection modes make up for each other to form complementation, the partial discharge condition can be comprehensively detected without replacing different types of sensors, and the reliability and the diversity of data acquired by the sensors are improved;
(2) the sensor has a state evaluation function, ultrasonic waves, ground waves and temperature test results are fused to score the switch cabinet, abnormal information is highlighted by adopting a variable weight strategy of correlation analysis, the situation that the abnormal information is easily submerged under the condition of constant weight is avoided, a reasonable and scientific evaluation system is established by combining environmental, service life and family defect factors, and the state of the switch cabinet is comprehensively evaluated;
(3) the working state of the sensor can be diagnosed through the self-checking function, the accuracy of detection data is ensured, and the reliability of the sensor is improved;
(4) the integrated signal acquisition, signal processing and data transmission functions are integrated, the connection through a cable is not needed, the sensor shell is installed and fixed on the outer surface of the switch cabinet in a magnetic type, the normal work of the switch cabinet is not influenced, the work flow is optimized, and the work efficiency is improved;
(5) the sensor adopts two power supply modes of a lithium battery and an external power supply, and two data transmission modes of a wired mode and a wireless mode can be flexibly selected according to application environments, so that the sensor is not only suitable for a live detection mode, but also suitable for an online monitoring mode, the compatibility of the sensor is improved, and the sensor is applied to the wider field of live detection.
Drawings
FIG. 1 is a schematic structural diagram of an integrated switch cabinet partial discharge intelligent sensor according to the present invention;
FIG. 2 is a schematic structural diagram of a conditioning module of the integrated switch cabinet partial discharge intelligent sensor according to the present invention;
FIG. 3 is a schematic structural diagram of an amplifying unit of the integrated switch cabinet partial discharge intelligent sensor of the invention;
FIG. 4 is a schematic structural diagram of an analog-to-digital conversion unit of the integrated switch cabinet partial discharge intelligent sensor according to the present invention;
FIG. 5 is a schematic structural diagram of a signal generating module of the integrated switch cabinet partial discharge intelligent sensor according to the present invention;
fig. 6 is a flowchart of an information fusion state evaluation method of the integrated switch cabinet partial discharge intelligent sensor according to the present invention.
Detailed Description
In order that those skilled in the art will better understand the technical solution of the present invention, the following detailed description is given with reference to the accompanying drawings:
the first embodiment is as follows:
referring to fig. 1 to 5, an embodiment of the present invention provides an integrated switch cabinet local discharge intelligent sensor, which includes a signal acquisition module 1, a conditioning module 2, a signal generation module 3, an MCU module 4, a communication module 5, and a power supply module 6, which are integrated together, and the local discharge intelligent sensor is magnetically attracted to an outer surface of the switch cabinet.
The signal acquisition module 1 consists of an ultrasonic sensor 12, a ground electric wave sensor 13 and a temperature sensor 11 (see fig. 1), wherein the ultrasonic sensor 12 acquires an ultrasonic signal generated when the switch cabinet is partially discharged and sends the ultrasonic signal to the conditioning module 2; the earth electric wave sensor 13 collects transient earth electric wave signals generated during partial discharge of the switch cabinet and sends the transient earth electric wave signals to the conditioning module 2; the temperature sensor 11 collects the surface temperature of the cabinet body during partial discharge of the switch cabinet and sends the surface temperature of the cabinet body to the conditioning module 2.
The conditioning module 2 is connected with the signal acquisition module 1, the conditioning module 2 is used for converting the received ultrasonic signals and the transient earth electric wave signals into partial discharge digital signals respectively, and sending the converted partial discharge digital signals to the MCU module 4, and the conditioning module 2 performs self-checking judgment.
The signal generating module 3 is connected with the conditioning module 2, and the signal generating module 3 is used for generating an ultrasonic analog signal and a ground electric wave analog signal and providing a standard analog signal source for the self-inspection of the equipment; the MCU module 4 is respectively connected with the conditioning module 2 and the signal generating module 3, the MCU module 4 is used for processing, analyzing and receiving the partial discharge digital signal, evaluating and judging the running state of the switch cabinet, and controlling the signal generating module 3 to send out an analog signal; communication module 5 is connected with MCU module 4, and communication module 5 transmits the data and the self-checking result of MCU module 4 to external data collection node through wired and wireless mode, and the self-checking order of receiving external data collection node and sending.
The power supply module 6 is used for supplying power to the conditioning module 2, the signal generation module 3, the MCU module 4 and the communication module 5. A lithium battery is arranged in the power supply module 6, an external power supply interface is reserved in the power supply module 6, and the power supply module 6 adopts two power supply modes of the lithium battery and the external power supply and can be flexibly selected according to the application environment.
Referring to fig. 2 again, the conditioning module 2 includes an amplifying unit 21, a filtering unit 22, a detecting unit 23, an analog-to-digital converting unit 24, and a self-checking judging unit 25, the amplifying unit 21, the filtering unit 22, the detecting unit 23, the analog-to-digital converting unit 24, and the self-checking judging unit 25 are connected in sequence, the analog-to-digital converting unit 24 is connected to the amplifying unit 21, wherein: the amplifying unit 21 is connected with the signal acquisition module 1, and the amplifying unit 21 is used for amplifying the ultrasonic signal and the transient earth electric wave signal output by the signal acquisition module 1; the amplifying unit 21 transmits the amplified ultrasonic signal to the filtering unit 22, and the amplifying unit 21 transmits the amplified transient earth electric wave signal to the analog-to-digital conversion unit 24; the filtering unit 22 is configured to perform filtering processing on the ultrasonic signal output by the amplifying unit 21; the detection unit 23 is configured to perform detection processing on the ultrasonic signal output by the filtering unit 22; the analog-to-digital conversion unit 24 is used for converting the ultrasonic signal output by the detection unit 23 and the earth electric wave signal output by the amplification unit 21 into digital signals respectively; the self-test judging unit 25 judges whether the partial discharge intelligent sensor works normally by comparing the self-test result output by the analog-to-digital conversion unit 24 with a preset threshold value.
Referring to fig. 3 and 4, the amplifying unit 21 includes an ultrasonic signal amplifying circuit 211 and a ground electric wave signal amplifying circuit 212, wherein the ultrasonic signal amplifying circuit 211 is configured to amplify the ultrasonic signal from the ultrasonic sensor 12; the ground electric wave signal amplification circuit 212 is used for carrying out nonlinear amplification on the transient ground electric wave signal from the ground electric wave sensor 13; the analog-to-digital conversion unit 24 includes an ultrasonic signal analog-to-digital conversion circuit 241 and a ground electric wave analog-to-digital conversion circuit 242, the ultrasonic signal analog-to-digital conversion circuit 241 is configured to convert the ultrasonic analog signal from the signal generation module 3 into a digital signal, and the ground electric wave signal analog-to-digital conversion circuit 241 is configured to convert the ground electric wave analog signal from the signal generation module 3 into a digital signal.
Referring to fig. 5, the signal generating module 3 includes a signal generating control unit 31, an ultrasonic analog signal generating unit 32, and a ground voltage analog signal generating unit 33, and the ultrasonic analog signal generating unit 32 and the ground voltage analog signal generating unit 33 are respectively connected to the signal generating control unit 31. The signal generating module 3 generates two types of analog signals to provide a local discharge signal source for the self-checking of the sensor so as to test whether the working state of the sensor is normal or not. After determining that the working state of the sensor is abnormal, the signal acquisition module 1 starts the local discharge signal acquisition work.
The signal generation control unit 31 is used for controlling the ultrasonic analog signal generation unit 32 and the ground voltage analog signal generation unit 33 to send out corresponding analog signals; the ultrasonic analog signal generating unit 32 is used for generating standard ultrasonic analog signals with fixed characteristics; the ground voltage analog signal generating unit 33 is used to generate a standard ground electric wave analog signal of a fixed characteristic.
The signal generation control unit 31 sends out a control signal when the partial discharge intelligent sensor is powered on and started, or sends out the control signal at regular time by setting a time interval, or sends out the control signal by receiving a self-test request sent by an external device, and the signal generation control unit 31 controls the ultrasonic analog signal generation unit 32 and the ground voltage analog signal generation unit 33 to send out corresponding analog signals through the control signal.
Communication module 5 adopts wired and wireless two kinds of communication mode, and communication module 5 is used for transmitting ultrasonic wave, transient state ground electric wave, cabinet body surface temperature's digital signal and self-checking result, and communication module 5 possesses the function that receives partial discharge intelligent sensor and starts the self-checking order to start self-checking order transmission to MCU module 4. The wired transmission mode utilizes the cable to connect the sensor and the acquisition device for data transmission, and the wireless transmission mode adopts the wireless network networking mode for data transmission, except transmitting ultrasonic waves, transient ground electric waves, digital signals of the surface temperature of the cabinet body and a self-checking result, the wired transmission mode also has the function of receiving a self-checking command started by the local discharge intelligent sensor, and sends the self-checking command to the MCU module 4.
The power supply module 6 adopts two power supply modes of a lithium battery and an external power supply, can supply power by using the lithium battery in low-power-consumption application scenes such as an inspection mode and the like, is convenient to carry and is beneficial to inspection and test; the high-power-consumption application scenes such as the online monitoring mode can be powered by an external power supply, and the service life of the battery is not limited. The sensor can be flexibly selected according to the application environment, so that the sensor can be applied to the wider field of charged detection.
According to the technical scheme of the integrated switch cabinet partial discharge intelligent sensor, all functional modules of the sensor are integrally designed and arranged in a structure, the sensor is arranged on the outer surface of a switch cabinet in a magnetic attraction mode, when the switch cabinet partial discharge intelligent sensor is powered on and started, self-checking is firstly carried out, after the self-checking is abnormal, the sensor carries out partial discharge signal acquisition and switch cabinet operation state evaluation, and acquired data, self-checking results and evaluation results are sent to an acquisition node. Besides the power-on self-test, the sensor can also automatically perform the self-test regularly or perform the self-test by receiving a self-test request sent by external equipment. The non-embedded integrated sensor integrates various detection technologies, can judge the working state of the sensor and locally evaluate the running state of the switch cabinet, and improves the functional diversity and the working reliability of the sensor; an extensible communication mode and a power supply mode are adopted, so that the compatibility of the sensor is improved; the installation is convenient, the work flow is simple, and the work efficiency is improved.
Example two:
taking 3 groups of monitoring values of the integrated switch cabinet local discharge intelligent sensor installed on a certain 3 switch cabinets (running for 5 years, without family defects and with the environmental temperature of 20 ℃) as an example, the monitoring values of the integrated local discharge intelligent sensor are shown in table 1:
Figure BDA0002502166840000091
TABLE 1
Referring to fig. 6, an information fusion state evaluation method for an integrated switch cabinet local discharge intelligent sensor includes the following steps:
s1, respectively calculating the fraction of each detection item according to three detection results of the geoelectric wave sensor, the ultrasonic sensor and the temperature sensor, wherein the formula is as follows:
Figure BDA0002502166840000101
wherein M isiScoring the ith detection item, wherein the detection items are geoelectric waves, ultrasonic waves and temperature respectively; when M isiWhen less than 0, let Mi0; when M isiWhen greater than 1, let Mi＝1；
Figure BDA0002502166840000102
The warning value of the ith detection item is 1.3 times of attention value, the attention value of the earth electric wave signal is 20dB of earth electric wave, the attention value of the ultrasonic wave signal is 8dB, the attention value of the temperature is T +20 ℃, wherein T is the ambient temperature;
Figure BDA0002502166840000103
the environment value of the ith detection item of the tested device is obtained;
Figure BDA0002502166840000104
is the measured value of the ith detection item; kFThe family defect coefficient is 0.95 for the part with family defect, and the family defect coefficient is 1 for the part without family defect; kTIs a life factor, KT(100-years of operation × 0.3.3)/100;
the score of each test item calculated by substituting 3 sets of data in table 1 into formula 1 is shown in table 2.
Numbering Ground electric wave Ultrasonic wave Temperature of cabinet
1 0.899 0.88 0.858
2 0.01 0.01 0.523
3 0.63 0.566 0.408
In table 2S2, the weighting factor of each test item is calculated according to the score of each test item, and the formula is:
Figure BDA0002502166840000105
wherein, WiThe weight coefficient of the ith detection item;
Figure BDA0002502166840000106
the constant weight coefficients of the ith detection item are 0.15, 0.35 and 0.5; miThe score of the ith test item; j is the number of detection items;
Figure BDA0002502166840000107
a constant weight coefficient for the jth detection term; mjThe score of the jth detection item; the calculation of the weight coefficient of each test item by substituting the score of each test item in table 2 into equation 2 is shown in table 3.
Numbering Ground electric wave Ultrasonic wave Temperature of cabinet
1 0.145 0.347 0.508
2 0.294 0.687 0.019
3 0.114 0.297 0.589
Table 3S3, calculating a composite state score according to the score of each test item and the weight coefficient, where the formula is:
Figure BDA0002502166840000111
wherein x is the total score after the information of the switch cabinet is fused; i is the number of detection items; miThe score of the ith test item; wiThe weight coefficient of the ith detection item;
substituting the values in tables 2 and 3 into equation 3, the composite status scores of the 3 sets of test values were calculated to be 0.872, 0.02, 0.28, respectively.
S4, solving a membership matrix according to the comprehensive score and a membership function, wherein the membership function formula is as follows:
health status:
Figure BDA0002502166840000112
and (3) normal state:
Figure BDA0002502166840000113
abnormal state:
Figure BDA0002502166840000114
early warning state:
Figure BDA0002502166840000115
and (4) alarm state:
Figure BDA0002502166840000116
membership matrix: f ═ F1(x)，f2(x)，f3(x)，f4(x)，f5(x) }; (formula 9)
The comprehensive state scores of 0.872, 0.02 and 0.28 are sequentially substituted into a formula 4 to a formula 8, and the membership degree matrix of 3 groups of monitoring values obtained according to the formula 9 is respectively as follows:
F1＝{0.86，0.28，0，0，0}
F2＝{0，0，0，0，1}
F3＝{0，0，0，0.9，0.1}
s5, evaluating the equipment state grade according to the membership matrix, and selecting the grade corresponding to the maximum membership as the comprehensive state grade of the switch cabinet by adopting the maximum membership principle, wherein f1(x)、f2(x)、f3(x)、f4(x)、f5(x) The one-to-one correspondence levels are health, normal, abnormal, early warning and alarm. Maximum of F1The value is f1(x), so the status level corresponding to the first set of monitored values is healthy; f2Maximum value of fs(x) Therefore, the state grade corresponding to the second group of monitoring values is alarming; f3Maximum value of f4(x) Therefore, the state grade corresponding to the third group of monitoring values is early warning.
The evaluation specification for each grade is shown in table 4:
Figure BDA0002502166840000121
TABLE 4
In practical application, the environment values of all detection items can be set in the intelligent sensor, the state grade of the switch cabinet is evaluated according to the detection result of the sensor, the running state of the switch cabinet is judged, and an overhaul scheme is formulated.
When the integrated switch cabinet local discharge intelligent sensor is used, when the switch cabinet local discharge intelligent sensor is powered on and started, the analog signal generating unit sends an analog signal, the sensor carries out self-checking, after the working state of the sensor is determined to be abnormal, the sensor carries out local discharge signal acquisition and switch cabinet running state evaluation, and acquired data, self-checking results and evaluation results are sent to the acquisition node through the communication module. Besides the power-on self-test, the sensor can also automatically perform the self-test regularly or perform the self-test by receiving a self-test request sent by external equipment.
The information fusion state evaluation method of the integrated switch cabinet local discharge intelligent sensor adopts three detection technologies of ultrasonic waves, transient ground voltage and cabinet body temperature, fuses test results of three state quantities, establishes a comprehensive grading model, and comprehensively judges the running state of the switch cabinet.
In summary, according to the integrated switch cabinet local discharge intelligent sensor and the information fusion state evaluation method thereof, the integrated switch cabinet local discharge intelligent sensor collects and processes ultrasonic waves, earth electric waves and cabinet body temperature signals, the obtained ultrasonic amplitude, earth voltage amplitude and cabinet body temperature value are used as the basis for evaluating the operation state of the switch cabinet, the correlated state quantities are fused into a comprehensive evaluation score, the relationship between the comprehensive evaluation score and the state grade is established by constructing a membership function, and finally the state of the switch cabinet is evaluated.
It should be understood by those skilled in the art that the above embodiments are only for illustrating the present invention and are not to be used as a limitation of the present invention, and that changes and modifications to the above described embodiments are within the scope of the claims of the present invention as long as they are within the spirit and scope of the present invention.

Claims (8)

1. The utility model provides an integral type cubical switchboard partial discharge intelligent sensor, its characterized in that, includes integrated signal acquisition module, conditioning module, signal generation module, MCU module, communication module and power module together, partial discharge intelligent sensor magnetism is inhaled at the surface of cubical switchboard, wherein:
the signal acquisition module consists of an ultrasonic sensor, a ground electric wave sensor and a temperature sensor, and the ultrasonic sensor acquires ultrasonic signals generated when the switch cabinet is partially discharged and sends the ultrasonic signals to the conditioning module; the ground electric wave sensor collects transient ground electric wave signals generated when the switch cabinet discharges locally and sends the transient ground electric wave signals to the conditioning module; the temperature sensor is used for acquiring the surface temperature of the cabinet body during partial discharge of the switch cabinet and sending the surface temperature of the cabinet body to the conditioning module;
the conditioning module is connected with the signal acquisition module, and is used for respectively converting the received ultrasonic signals and transient earth electric wave signals into partial discharge digital signals and sending the converted partial discharge digital signals to the MCU module, and the conditioning module performs self-checking judgment;
the signal generating module is connected with the conditioning module and is used for generating ultrasonic analog signals and earth electric wave analog signals and providing standard analog signal sources for equipment self-inspection;
the MCU module is respectively connected with the conditioning module and the signal generating module and is used for processing, analyzing and receiving the partial discharge digital signal, evaluating and judging the running state of the switch cabinet and controlling the signal generating module to send an analog signal;
the communication module is connected with the MCU module, transmits the data and the self-checking result of the MCU module to an external data collecting node in a wired and wireless mode, and receives a self-checking command sent by the external data collecting node;
and the power supply module is used for supplying power to the conditioning module, the signal generation module, the MCU module and the communication module.
2. The intelligent sensor of claim 1, wherein the conditioning module comprises an amplifying unit, a filtering unit, a detecting unit, an analog-to-digital conversion unit, and a self-checking unit, the amplifying unit, the filtering unit, the detecting unit, the analog-to-digital conversion unit, and the self-checking unit are sequentially connected, the analog-to-digital conversion unit is connected to the amplifying unit, and wherein:
the amplification unit is connected with the signal acquisition module and is used for amplifying the ultrasonic signals and the transient earth electric wave signals output by the signal acquisition module; the amplifying unit transmits the amplified ultrasonic signals to the filtering unit, and the amplifying unit transmits the amplified transient ground electric wave signals to the analog-to-digital conversion unit;
the filtering unit is used for filtering the ultrasonic signal output by the amplifying unit;
the wave detection unit is used for carrying out wave detection processing on the ultrasonic wave signal output by the filtering unit;
the analog-to-digital conversion unit is used for respectively converting the ultrasonic wave signal output by the detection unit and the earth electric wave signal output by the amplification unit into digital signals;
and the self-checking judgment unit judges whether the partial discharge intelligent sensor works normally or not by comparing the self-checking result output by the analog-to-digital conversion unit with a preset threshold value.
3. The intelligent sensor for partial discharge of integrated switch cabinet as claimed in claim 2,
the amplification unit comprises an ultrasonic signal amplification circuit and a ground electric wave signal amplification circuit, and the ultrasonic signal amplification circuit is used for amplifying the ultrasonic signal from the ultrasonic sensor; the earth electric wave signal amplifying circuit is used for carrying out nonlinear amplification on the transient earth electric wave signal from the earth electric wave sensor;
the analog-to-digital conversion unit comprises an ultrasonic signal analog-to-digital conversion circuit and a ground electric wave analog-to-digital conversion circuit, the ultrasonic signal analog-to-digital conversion circuit is used for converting the ultrasonic analog signals from the signal generation module into digital signals, and the ground electric wave signal analog-to-digital conversion circuit is used for converting the ground electric wave analog signals from the signal generation module into digital signals.
4. The intelligent sensor for partial discharge of integrated switch cabinet as claimed in claim 1, wherein the signal generation module comprises a signal generation control unit, an ultrasonic analog signal generation unit and a ground voltage analog signal generation unit, the ultrasonic analog signal generation unit and the ground voltage analog signal generation unit are respectively connected with the signal generation control unit, wherein:
the signal generation control unit is used for controlling the ultrasonic analog signal generation unit and the ground voltage analog signal generation unit to send out corresponding analog signals;
the ultrasonic analog signal generating unit is used for generating standard ultrasonic analog signals with fixed characteristics;
the ground voltage analog signal generating unit is used for generating a standard ground voltage analog signal with fixed characteristics.
5. The intelligent sensor for partial discharge of the integrated switch cabinet as claimed in claim 4, wherein the signal generation control unit sends out a control signal when the intelligent sensor for partial discharge is powered on, or sends out a control signal at regular time intervals, or sends out a control signal by receiving a self-checking request sent by an external device, and the signal generation control unit controls the ultrasonic analog signal generation unit and the ground voltage analog signal generation unit to send out corresponding analog signals through the control signal.
6. The intelligent sensor for partial discharge of the integrated switch cabinet as claimed in claim 1, wherein the communication module adopts two communication modes, namely wired communication and wireless communication, is used for transmitting ultrasonic waves, transient ground waves, digital signals of the surface temperature of the cabinet body and self-checking results, and has a function of receiving a self-checking command for starting the intelligent sensor for partial discharge, and sending the self-checking command for starting to the MCU module.
7. The intelligent sensor for partial discharge of integrated switch cabinet according to claim 1, wherein a lithium battery is disposed in the power supply module, and an external power interface is reserved in the power supply module.
8. The information fusion state evaluation method of the integrated switch cabinet partial discharge intelligent sensor as claimed in claim 1, characterized by comprising the following steps:
s1, respectively calculating the fraction of each detection item according to three detection results of the geoelectric wave sensor, the ultrasonic sensor and the temperature sensor, wherein the formula is as follows:
Figure FDA0002502166830000031
wherein M isiScoring the ith detection item, wherein the detection items are geoelectric waves, ultrasonic waves and temperature respectively; when M isiWhen less than 0, let Mi0; when M isiWhen greater than 1, let Mi＝1；
Figure FDA0002502166830000032
The warning value of the ith detection item is 1.3 times of attention value, the attention value of the earth electric wave signal is 20dB of the earth electric wave, and the ultrasonic signal noteThe mean value is 8dB, the temperature attention value is T +20 ℃, wherein T is the ambient temperature;
Figure FDA0002502166830000033
the environment value of the ith detection item of the tested device is obtained;
Figure FDA0002502166830000034
is the measured value of the ith detection item; kFThe family defect coefficient is 0.95 for the part with family defect, and the family defect coefficient is 1 for the part without family defect; kTIs a life factor, KT(100-years of operation × 0.3.3)/100;
s2, calculating the weight coefficient of each detection item according to the score of each detection item, wherein the formula is as follows:
Figure FDA0002502166830000035
wherein, WiThe weight coefficient of the ith detection item;
Figure FDA0002502166830000036
the constant weight coefficients of the ith detection item are 0.15, 0.35 and 0.5; miThe score of the ith test item; j is the number of detection items;
Figure FDA0002502166830000037
a constant weight coefficient for the jth detection term; mjThe score of the jth detection item;
s3, calculating the comprehensive state score according to the scores of the detection items and the weight coefficient, wherein the formula is as follows:
Figure FDA0002502166830000038
wherein x is the total score after the information of the switch cabinet is fused; i is the number of detection items; miIs as followsScoring the i test items; wiThe weight coefficient of the ith detection item;
s4, solving a membership matrix according to the comprehensive score and a membership function, wherein the membership function formula is as follows:
health status:
Figure FDA0002502166830000041
and (3) normal state:
Figure FDA0002502166830000042
abnormal state:
Figure FDA0002502166830000043
early warning state:
Figure FDA0002502166830000044
and (4) alarm state:
Figure FDA0002502166830000045
membership matrix: f ═ F1(x)，f2(x)，f3(x)，f4(x)，f5(x)}；
S5, evaluating the equipment state grade according to the membership matrix, and selecting the grade corresponding to the maximum membership as the comprehensive state grade of the switch cabinet by adopting the maximum membership principle, wherein f1(x)、f2(x)、f3(x)、f4(x)、f5(x) The one-to-one correspondence levels are health, normal, abnormal, early warning and alarm.
CN202010439619.8A 2020-05-21 2020-05-21 Integrated switch cabinet partial discharge intelligent sensor and information fusion state evaluation method thereof Pending CN111579945A (en)

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