CN111426473B - GIS (gas insulated switchgear) equipment defect detection system and method by utilizing sweep frequency alternating current - Google Patents
GIS (gas insulated switchgear) equipment defect detection system and method by utilizing sweep frequency alternating current Download PDFInfo
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- CN111426473B CN111426473B CN202010423254.XA CN202010423254A CN111426473B CN 111426473 B CN111426473 B CN 111426473B CN 202010423254 A CN202010423254 A CN 202010423254A CN 111426473 B CN111426473 B CN 111426473B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M13/00—Testing of machine parts
- G01M13/02—Gearings; Transmission mechanisms
- G01M13/028—Acoustic or vibration analysis
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/04—Analysing solids
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/02—Indexing codes associated with the analysed material
- G01N2291/023—Solids
- G01N2291/0234—Metals, e.g. steel
Abstract
The invention discloses a GIS equipment defect detection system and method utilizing sweep frequency alternating current, which comprises a variable frequency power supply, a current booster, an adjustable resistor, a vibration sensor, a data acquisition device and a vibration test system, wherein the variable frequency power supply is connected with the adjustable resistor in series after passing through the current booster and is connected with GIS equipment to form a loop, the vibration sensor is arranged on a GIS equipment shell, the data acquisition device acquires vibration signals and transmits the vibration signals to the vibration test system, and the vibration test system performs frequency spectrum analysis on the vibration signals and identifies the type of mechanical defects of the electrical equipment. The invention judges and identifies the mechanical fault type of the equipment by detecting and analyzing the vibration signal under the sweep frequency alternating current, and can detect the internal mechanical defects of the GIS equipment.
Description
Technical Field
The invention relates to GIS equipment mechanical defect diagnosis, in particular to a GIS equipment defect detection system and method by utilizing sweep frequency alternating current.
Background
GIS is totally closed combined power equipment, and once an accident occurs, the consequences caused by the accident are more serious than that of open equipment, the fault repair is particularly complex, and the power failure range is large. In the existing GIS fault detection methods developed more maturely, for example, a pulse current method, a light method, a sound method, and the like, most of them are discharge faults, and in the actual operation of the GIS, besides the discharge faults, mechanical defects are also a major cause of accidents, and the occurrence of the GIS mechanical defect faults has a great influence on the safe and stable operation of the power system and is difficult to detect.
At present, there are two main methods for detecting the mechanical state of the GIS equipment. One is to carry out characteristic detection of opening and closing operations, such as a system and a method disclosed in chinese patent specification CN102928069A, but the method can only obtain motion parameters of moving parts such as circuit breakers and disconnectors, and can only indirectly reflect the operating states of a few moving parts in an operating mechanism, and it is difficult to detect mechanical defects such as looseness of internal parts of GIS equipment, misalignment of conductors, and abnormal connection of bus contacts. The other method is to carry out vibration characteristic detection of GIS equipment, such as the systems and methods disclosed in Chinese patent specifications CN105629100A and CN104749468A, but the methods only detect vibration signals of the equipment under the condition of fixed excitation, so that the characteristic vibration signals caused by partial defects cannot be effectively excited and detected, and the problem of low defect detection sensitivity exists.
Disclosure of Invention
The purpose of the invention is as follows: aiming at the problems, the invention provides a GIS equipment defect detection system and method by utilizing sweep frequency alternating current, which can effectively detect the mechanical defects of GIS equipment.
The technical scheme is as follows: in order to realize the purpose of the invention, the technical scheme adopted by the invention is as follows: a GIS equipment defect detection system utilizing sweep frequency alternating current comprises a variable frequency power supply, a current booster, an adjustable resistor, a vibration sensor, a data acquisition device and a vibration test system; the output end of the variable frequency power supply is connected with the primary side of the current booster, and the secondary side of the current booster, the adjustable resistor and the GIS equipment are connected in series to form a loop; the tail end of the GIS equipment is grounded; the vibration sensor is arranged on the outer surface of the GIS equipment and is connected to the vibration testing system through the data acquisition device; the data acquisition device acquires vibration signals and uploads the vibration signals to the vibration test system; changing the alternating current frequency of a variable frequency power supply to obtain a plurality of groups of vibration signals; and the vibration test system performs spectrum analysis on the multiple groups of vibration signals and identifies the type of mechanical defects of the GIS equipment.
Further, the variable frequency power supply comprises a capacitance compensation device.
Further, the current booster includes a plurality of variable ratio taps.
Furthermore, a vibration sensor is respectively fixed on the same axial section of the GIS device in the horizontal direction and the vertical direction, the two vibration sensors form a group, and a group of sensors is arranged at fixed intervals in the axial direction of the GIS device.
Furthermore, the data acquisition device can simultaneously acquire data of a plurality of groups of vibration sensors and perform analog-to-digital conversion.
Further, the vibration sensor is a miniature piezoelectric uniaxial acceleration sensor; the vibration test system is a PC upper computer.
A GIS equipment defect detection method using sweep frequency alternating current comprises the following steps:
step 1: the variable frequency power supply outputs alternating current with specific frequency;
step 2: the current booster amplifies the alternating current and applies the amplified alternating current to GIS equipment;
and step 3: the vibration sensor is arranged on the surface of the GIS equipment, and the data acquisition device acquires vibration signals and forms a spectrogram after the vibration signals are converted by the vibration test system;
and 4, step 4: changing the frequency of the alternating current output by the variable frequency power supply, and repeating the steps 1-3 to obtain a plurality of groups of spectrograms;
and 5: and the vibration test system analyzes the multiple groups of frequency spectrograms and identifies the type of mechanical defects of the GIS equipment.
Further, in step 1, the variable frequency power supply includes a capacitance compensation device, and the input amount of the compensation capacitor is automatically adjusted to compensate the reactive power.
Further, the step 2 further comprises adjusting a tap of the current booster to output a rated current of a specified magnitude.
Further, in the step 5, the vibration testing system performs feature analysis on the multiple groups of frequency spectrums by using at least one of a feature frequency comparison method, an entropy spectrum method and a cluster analysis method, so as to identify the category of the mechanical defect of the GIS equipment.
Has the advantages that: the method judges and identifies the mechanical fault type of the GIS equipment through detection and analysis of the vibration signals under the sweep frequency alternating current, has rich frequency spectrum, can detect the internal mechanical defects of various electrical equipment, has high sensitivity, improves the defect detection efficiency, and saves the maintenance cost of the electrical equipment.
Drawings
Fig. 1 is a schematic diagram of a GIS device defect detection system using swept ac current according to the present invention.
Detailed Description
The technical solution of the present invention is further described below with reference to the accompanying drawings and examples.
As shown in fig. 1, the system for detecting defects of a GIS device using swept-frequency ac current according to the present invention includes a variable frequency power supply 1, a current booster 2, an adjustable resistor 3, a vibration sensor 4, a data acquisition device 5, and a vibration test system 6; the output end of the variable frequency power supply 1 is connected with the primary side of the current booster 2, and the secondary side of the current booster 2, the adjustable resistor 3 and the GIS equipment 7 are connected in series through copper wires to form a loop; the GIS device 7 is grounded at the end. In the embodiment, the output capacity of the variable frequency power supply 1 is not lower than 100kVA, and the output current of the current booster 2 is not lower than 4000A.
The variable frequency power supply 1 outputs alternating currents of different frequencies through rectification and inversion of a power electronic device and also comprises a capacitance compensation device. The variable frequency power supply 1 can detect the phase angle difference between the output voltage and the current and automatically control the input quantity of the compensation capacitor, so that the efficiency of the power supply to output the current is highest. In the embodiment, the variable frequency power supply comprises 14 capacitance compensation devices, and the rated capacity of each capacitance compensation device is 30 kVar.
The current booster comprises a plurality of variable ratio taps, and the variable ratio of the primary side and the secondary side can be changed by replacing the taps connected with the variable frequency power supply 1, so that the current boosting multiple is adjusted.
One end of the adjustable resistor 3 is connected with the output end of the secondary side of the current booster 2, the other end of the adjustable resistor is connected with the input end of the GIS equipment 7, the damping of the whole electric loop is changed by adjusting the size of the adjustable resistor 3, and meanwhile, the protection effect on the whole loop is achieved.
The vibration sensor 4 is arranged on the outer surface of the GIS equipment 7, and the vibration sensor 4 is connected to the vibration testing system 6 through the data acquisition device 5; the data acquisition device 5 acquires vibration signals and uploads the vibration signals to the vibration test system 6; changing the alternating current frequency of the variable frequency power supply 1 to obtain a plurality of groups of vibration signals; and the vibration test system 6 performs spectrum analysis on the multiple groups of vibration signals and identifies the type of mechanical defects of the GIS equipment.
The vibration sensor 4 can be fixed on the housing of the GIS device 7 in various ways; magnetic base magnetic force installation, magic area ligature, glue fixed mounting also can be through installing vibration sensor on the base with the screw behind electrical equipment surface mounting fixed base. The vibration sensor 4 converts the vibration signal collected from the GIS device 7 into a voltage signal. In this embodiment, a vibration sensor 4 is fixed on each of the horizontal and vertical directions of the same cross section of the GIS device 7, the two vibration sensors 4 form a group, a group of sensors is fixed at intervals of 0.5m in the axial direction, and the tail ends of the vibration sensors 4 are connected with the data acquisition device 5 through signal cables. The vibration sensor 4 adopts a miniature piezoelectric uniaxial acceleration sensor, the sensitivity is 80-200 mV/g, the measurement range is 5-50g, and the central frequency range is 0.1-5000 Hz.
The data acquisition device 5 is a data acquisition card, the data acquisition card is connected with the vibration test system 6 through an optical cable or a wireless signal, the vibration test system 6 can perform frequency spectrum analysis on a time domain signal obtained by vibration, and a characteristic frequency method, an entropy spectrum method and a clustering analysis method are adopted to perform characteristic analysis on the frequency spectrum, identify the type of mechanical defects of the electrical equipment, and simultaneously position the fault position according to time difference positioning and amplitude comparison positioning. In this embodiment, the vibration testing system 6 is a PC upper computer. The data acquisition device can simultaneously acquire more than 6 groups of sensor data, transmits the acquired signals to a PC upper computer for spectrum analysis, judges whether the mechanical structure of the electrical equipment has defects according to the spectrum analysis result, and judges the positions of the defects.
A GIS equipment defect detection method using sweep frequency alternating current comprises the following steps:
(1) adjusting the variable frequency power supply 1 to output an alternating current with a specific frequency; the variable frequency power supply also comprises a capacitance compensation device, and the input quantity of compensation capacitors is automatically adjusted according to the load condition so as to compensate the reactive power;
(2) adjusting a tap of the current booster and outputting rated current with specified magnitude; the current booster 2 amplifies the alternating current and applies the amplified alternating current to the GIS equipment 7;
(3) the vibration sensor 4 is arranged on the surface of the GIS equipment 7, and the data acquisition device 5 acquires vibration signals and forms a spectrogram after the vibration signals are converted by the vibration test system 6;
(4) changing the frequency of the alternating current output by the variable frequency power supply 1, and repeating the steps (1) - (3) to obtain a plurality of groups of spectrograms;
(5) the vibration test system 6 analyzes the multiple groups of frequency spectrograms and identifies the type of mechanical defects of the GIS equipment 7; the vibration testing system adopts a characteristic frequency comparison method, an entropy spectrum method and a cluster analysis method to carry out characteristic analysis on the frequency spectrogram and identify the type of mechanical defects of the GIS equipment.
The invention can cause the vibration response of the electrical equipment by applying alternating current excitation with different frequencies, detect the vibration response and realize the diagnosis and identification of mechanical defects of the equipment by analyzing the vibration frequency spectrum.
As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting the same, and although the present invention is described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications and equivalents may be made to the embodiments of the invention without departing from the spirit and scope of the invention, which is to be covered by the claims.
Claims (4)
1. A GIS equipment defect detection system utilizing sweep frequency alternating current is characterized by comprising a variable frequency power supply (1), a current booster (2), an adjustable resistor (3), a vibration sensor (4), a data acquisition device (5) and a vibration test system (6); the output end of the variable frequency power supply (1) is connected with the primary side of the current booster (2), and the secondary side of the current booster (2), the adjustable resistor (3) and the GIS equipment (7) are connected in series to form a loop; the variable frequency power supply (1) comprises a capacitance compensation device, and the current booster (2) comprises a plurality of variable ratio taps; the tail end of the GIS equipment (7) is grounded;
the vibration sensors (4) are respectively fixed on the same axial section of the GIS device in the horizontal and vertical directions, the two vibration sensors (4) form a group, and the group of sensors are arranged at fixed intervals in the axial direction of the GIS device; the vibration sensor (4) is arranged on the outer surface of the GIS equipment (7), and the vibration sensor (4) is connected to the vibration testing system (6) through the data acquisition device (5); the data acquisition device (5) acquires vibration signals and uploads the vibration signals to the vibration test system (6); changing the alternating current frequency of the variable frequency power supply (1) to obtain a plurality of groups of vibration signals; and the vibration test system (6) performs spectrum analysis on the multiple groups of vibration signals and identifies the type of mechanical defects of the GIS equipment.
2. A system as claimed in claim 1, wherein the data acquisition device is configured to acquire data from a plurality of vibration sensors and perform analog-to-digital conversion.
3. A GIS device defect detection system using swept-frequency alternating current according to claim 1, wherein the vibration sensor is a miniature piezoelectric uniaxial acceleration sensor; the vibration test system is a PC upper computer.
4. A method for detecting defects of GIS equipment using the system for detecting defects of GIS equipment of claim 1, comprising the steps of:
step 1: the variable frequency power supply (1) outputs alternating current with specific frequency, and the variable frequency power supply (1) comprises a capacitance compensation device and is used for automatically adjusting the input quantity of compensation capacitors to compensate reactive power;
step 2: the current booster (2) amplifies the alternating current and applies the amplified alternating current to GIS equipment (7), and rated current with specified magnitude is output by adjusting a tap of the current booster (2);
and step 3: the vibration sensor (4) is arranged on the surface of the GIS equipment (7), and the data acquisition device (5) acquires vibration signals and forms a spectrogram after the vibration signals are converted by the vibration test system (6);
and 4, step 4: changing the frequency of the alternating current output by the variable frequency power supply (1), and repeating the steps 1-3 to obtain a plurality of groups of spectrograms;
and 5: the vibration testing system (6) analyzes the multiple groups of frequency spectrums by adopting at least one of a characteristic frequency comparison method, an entropy spectrum method and a cluster analysis method, and identifies the category of the mechanical defects of the GIS equipment (7).
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| CN202010423254.XA CN111426473B (en) | 2020-05-19 | 2020-05-19 | GIS (gas insulated switchgear) equipment defect detection system and method by utilizing sweep frequency alternating current |
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| CN112924827A (en) * | 2021-01-29 | 2021-06-08 | 国网电力科学研究院武汉南瑞有限责任公司 | GIS defect diagnosis device and method based on sweep frequency current method |
| CN113607271A (en) * | 2021-07-15 | 2021-11-05 | 国网电力科学研究院武汉南瑞有限责任公司 | GIL defect online monitoring system and method based on vibration signals |
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