CN112540272B - GIS equipment mechanical vibration abnormal sound defect simulation system and method - Google Patents
GIS equipment mechanical vibration abnormal sound defect simulation system and method Download PDFInfo
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- 230000007547 defect Effects 0.000 title claims abstract description 146
- 230000002159 abnormal effect Effects 0.000 title claims abstract description 81
- 238000004088 simulation Methods 0.000 title claims abstract description 63
- 238000000034 method Methods 0.000 title claims abstract description 28
- 238000001514 detection method Methods 0.000 claims abstract description 45
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- 229910052751 metal Inorganic materials 0.000 claims abstract 2
- 239000002184 metal Substances 0.000 claims abstract 2
- 238000012360 testing method Methods 0.000 claims description 22
- 239000002808 molecular sieve Substances 0.000 claims description 17
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 claims description 17
- 239000003990 capacitor Substances 0.000 claims description 15
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- 229910018503 SF6 Inorganic materials 0.000 claims description 10
- SFZCNBIFKDRMGX-UHFFFAOYSA-N sulfur hexafluoride Chemical compound FS(F)(F)(F)(F)F SFZCNBIFKDRMGX-UHFFFAOYSA-N 0.000 claims description 10
- 229960000909 sulfur hexafluoride Drugs 0.000 claims description 10
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- 229910052802 copper Inorganic materials 0.000 claims description 3
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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
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Abstract
The invention relates to a GIS equipment mechanical vibration abnormal sound defect simulation system and a method, which belong to the field of gas insulated metal closed switch equipment, and comprise a main loop and vibration abnormal sound defect simulation module, a resonance boosting and induction current rising module, a vibration characteristic detection module, a measurement and operation control module and a grounding and overcurrent protection module; the system can realize the simulation setting of the operation type abnormal sound mechanical defects of the units such as the circuit breaker, the isolating switch, the grounding switch and the like and the related periodic abnormal sound defects such as abrasion, fatigue, looseness and the like of the conductive loop and the low-potential loop, and meanwhile, the vibration characteristic change under the load change can be analyzed. The system has flexible and various mechanical vibration abnormal sound defects, is equivalent to actual engineering and has strong practicability.
Description
Technical Field
The invention belongs to the field of gas-insulated metal-enclosed switchgear, and relates to a GIS equipment mechanical vibration abnormal sound defect simulation system and method.
Background
The gas-insulated metal-enclosed switchgear (Gas Insulated Switchgear-GIS) has the characteristics of high reliability, low maintenance cost, small occupied area and the like, is widely used, and mainly plays a role in control and protection in a power system. However, during the operation of the GIS equipment, faults caused by insulation and mechanical defects still occur, especially the mechanical defects exist, and the GIS equipment has the characteristics of multiple defect latency types, large hazard, difficult maintenance and the like. When the GIS equipment has the defects of poor contact of contacts, loosening of bolts of conductive fasteners and the like, abnormal sound vibration can be generated under the action of alternating electric power generated by operating force of a switch and load current. The long-term vibration defect can generate damages such as sulfur hexafluoride gas leakage, damage to the basin-type insulator or the insulating support, and the like, and the accidents such as conductor short circuit, insulation breakdown and the like can be caused even gradually. Therefore, the research on the internal mechanical defects of the GIS equipment is enhanced, the vibration rule of the GIS equipment under the defect and load change is mastered, and the detection technical means is provided, so that the safety operation of the equipment is guaranteed.
The invention provides a GIS vibration early warning system combining a multipoint sensor, a monitoring terminal and a threshold diagnosis method, which mainly aims at GIS bus vibration and does not relate to simulation methods of other parts and specific defects of a GIS. The invention provides a GIS equipment mechanical defect diagnosis system based on vibration detection and a GIS equipment mechanical defect diagnosis method based on combination of a fingerprint database and a diagnosis module, and mainly focuses on diagnosis of vibration defects. Liu Baowen et al studied a GIS mechanical fault diagnosis and test analysis method based on an S-transform D-SVM AlexNet model, and mainly aims at the impact vibration characteristics of a GIS breaker operating mechanism.
To summarize, the following main problems still exist in the aspect of simulating the mechanical vibration abnormal sound defect of the GIS equipment at present:
1) Much attention is paid to the operation type mechanical vibration, and the periodic abnormal sound vibration is less studied. At present, detection methods aiming at GIS insulation defect research are various and cover physical and chemical related detection methods such as sound, light, electricity, moisture, gas and the like. However, mechanical defects of the GIS are often concentrated on abnormal vibration caused by jamming or fatigue of an operating mechanism of the circuit breaker in the action process, and abnormal sound vibration caused by loosening defects of parts, fatigue loosening faults of springs and other abnormal sound defects caused by loosening of fastening bolts in the GIS in an operating state is less focused on.
2) There is a lack of simulation of different types of vibration defects and comparative study of vibration fingerprint characteristics. Because GIS equipment internal structure unit is various complicated, be difficult to dismantle. Especially for GIS equipment in field operation, the maintenance work is complicated, and the power failure maintenance time is long. Therefore, the existing GIS equipment internal mechanical defect research often presents characteristics such as caseness, locality, type deficiency and the like, does not fully conduct classification comparison research on GIS internal mechanical defects with multiple types, components and defect degrees, and does not establish a complete vibration characteristic fingerprint and a complete data characteristic library.
3) The comparative research on the vibration characteristics of split type and integrated type real GIS equipment under the condition of high voltage and high current loading is lacking. Firstly, a comparison research platform for vibration characteristics of split type and integrated type real GIS equipment is lacking at present, the existing platform can only carry out single loading of voltage or current, cannot carry out coupling effect research, and cannot fully simulate the running vibration state of the on-site GIS equipment; secondly, the existing simple GIS equipment vibration characteristic simulation device is far from the field split type and the common type real GIS equipment, and the vibration characteristic simulation has limitations.
Disclosure of Invention
In view of the above, the present invention is to provide a system and a method for simulating mechanical vibration abnormal noise defects of a GIS device, which can realize the simulation setting of the operation abnormal noise mechanical defects of a circuit breaker, a disconnecting switch, a grounding switch and other units, and the related periodic abnormal noise defects such as wear, fatigue, looseness and the like of a conductive loop and a low-potential loop, and can analyze the vibration characteristic change under the load change.
In order to achieve the above purpose, the present invention provides the following technical solutions:
on one hand, the invention provides a GIS equipment mechanical vibration abnormal sound defect simulation system, which comprises a main loop and vibration abnormal sound defect simulation module, a resonance boosting and induction current rising module, a vibration characteristic detection module, a measurement and operation control module and a grounding and overcurrent protection module;
the main circuit and the vibration abnormal sound defect simulation module are used for completing defect simulation actions, and comprise a main circuit formed by connecting a circuit breaker, a current booster, a grounding switch, a disconnecting switch and an acceleration sensor, and also comprise a high-voltage sleeve arranged on the circuit breaker, wherein insulating gas is filled in the main circuit, and an insulating supporting plate is used for supporting and isolating the main circuit and the ground;
the resonance boosting and induction current rising module is used for generating a load for the main loop and comprises a resonance boosting part and an induction current rising part; the resonance boosting part comprises a test transformer group, a reactor and a first capacitor which are connected in parallel and sequentially in series, the reactor forms a tuning transformer combination through the test transformer group, the reactor and the first capacitor generate series resonance under the power frequency, the resonance boosting part is connected to a high-voltage sleeve, and the test transformer group comprises a first test transformer and a second test transformer; the induction current rising part comprises a power supply, a third test transformer and a second capacitor which are connected in series, and is connected with the current rising device;
the vibration characteristic detection module comprises a piezoelectric acceleration sensor, a signal acquisition card and a signal conditioner which are connected with the upper computer, and is used for carrying out A/D conversion, signal conditioning and filtering treatment on vibration signals of the GIS defect simulation loop, uploading the vibration signals to the upper computer for carrying out modal decomposition and spectrum conversion, and realizing extraction of characteristic quantity and identification of mechanical abnormal sound defect modes;
the measuring and operating control module is used for measuring, displaying and lifting control of the voltage and current signals;
the grounding and overcurrent protection module is used for automatically cutting off a circuit when the current exceeds a set value.
Further, the main loop and the vibration abnormal sound defect simulation module are independent and split, and comprise three identical main loops, each main loop is provided with a high-voltage sleeve, and each main loop is supported and isolated by an insulating support plate; the high-voltage sleeve of each main loop is connected with the same resonance boosting part in a common way, and the current rising device of each main loop is connected with an induction current rising part respectively.
Further, the main loop and the vibration abnormal sound defect simulation module are three-phase integrated, only one main loop is arranged, three high-voltage sleeves are arranged on the main loop and are jointly connected with the same resonance boosting part, and three induction boosting parts are connected in parallel with a current booster of the main loop.
Further, the insulating gas filled in the main loop is sulfur hexafluoride, a demagnetizing aluminum alloy shell is arranged outside the main loop, bolts and basin-type insulators are used for supporting or fastening the shell, copper is used as a conductive material in the inner conductor of the main loop, and a moving contact or a fixed contact is used for steering and connecting the conductor and the conductor.
Further, the main loop is also connected with a lightning arrester, a voltage transformer and a current transformer, and a molecular sieve container is embedded in the main loop.
Further, the measuring and operation control module measures the voltage of the input end by utilizing a transformer to be connected with a voltage transformer and a voltmeter, measures the voltage output after resonance boosting by utilizing a voltage divider and an electrostatic voltmeter, measures the current change of each phase of wire by externally adding a current transformer to each phase of wire of each main loop, drives a direct current motor to lift and control the current and the voltage by a key of a control console, and displays the current and the voltage in real time by a digital meter.
On the other hand, the invention provides a GIS equipment mechanical vibration abnormal sound defect simulation method, which comprises the following steps:
s1: setting mechanical abnormal sound defects;
s2: vibration detection module installation, system wiring and loop checking;
s3: voltage current regulation and vibration detection.
Further, the step S1 specifically includes:
s11: releasing and storing sulfur hexafluoride gas;
s12: disassembling and hoisting the defect related structural units;
s13: the defect setting comprises defect setting of a disconnecting switch, a long guide rod contact seat and a molecular sieve adsorbent container;
s14: refastening of the defect-related structural units;
s15: sulfur hexafluoride gas is injected into the loop to a standard pressure level;
the isolating switch defect setting comprises the following steps: (1) disassembling a spring of the isolating switch, and setting a spring fatigue loosening defect; (2) disassembling or loosening bolts of a shielding cover of the isolating switch, and setting a loosening defect of the bolts of the shielding cover; (3) adjusting an operation handle of the isolating switch, and adopting a loop resistance meter; (4) the method comprises the steps of connecting a main loop in series to measure the contact state of a contact finger of an isolating switch, and setting the defect of poor contact of a contact;
the defect setting of the long guide rod contact seat comprises the following steps: loosening or disassembling one or more bolts of the guide rod, which are in contact with the base, and setting the loosening defect of the bolts of the long guide rod contact base;
the molecular sieve adsorbent vessel defect placement includes: and disassembling or dismantling one or more bolts of the molecular sieve vessel, and setting the loosening defect of the bolts of the molecular sieve vessel.
Further, in step S2, the method specifically includes the following steps:
s21: the vibration detection module is installed, the installation base is a plastic base without eddy current loss, the base is fixed to the position of the defect equipment, the coupling agent is used for improving the signal coupling characteristic between the base and the detection module, and the module signal wire is sequentially connected with a sensor terminal, detection equipment and an upper computer at the detection position;
s22: the system wiring is connected to form the GIS equipment mechanical vibration abnormal sound defect simulation system;
s23: and after the wiring is finished, carrying out loop inspection again to ensure no short circuit and disconnection, and taking down the grounding electrode.
Further, the step S3 specifically includes:
s31: adjusting current and voltage signals to carry out single loading or coupling loading of a load;
s32: detecting abnormal sound vibration signals;
s33: after vibration detection is finished, the current and the voltage are slowly reduced to 0, and then the electric switch is disconnected.
The invention has the beneficial effects that: compared with the prior art, first, the main loop of the defect simulation device integrates operating mechanism components such as a true breaker, a grounding switch, a disconnecting switch and the like, and is also provided with GIS equipment components such as a true lightning arrester, a voltage transformer, a current transformer, a molecular sieve container and the like, so that the device is complete in type, can be used for setting mechanical vibration defects of a plurality of components, is flexible and various, and simultaneously provides a method for setting mechanical abnormal sound vibration defects of different components. Secondly, the defect simulation device establishes two loop types of single-phase independent type and three-phase integrated type GIS equipment, accords with the actual engineering condition, can simulate the vibration signal difference and interaction characteristics under the electromagnetic coupling action between phases, and can simulate the vibration characteristics of single-phase independent GIS equipment. Thirdly, the defect simulation device introduces a mode of resonance boosting and induction current rising, establishes a high-voltage high-current coupling loading system, and can realize vibration state simulation of GIS equipment under different load conditions. Fourth, when mechanical abnormal sound vibration defect simulation, this patent has contained vibration signal detection analysis module, has realized vibration signal's collection, conditioning and signal processing, can real-time monitoring vibration characteristic, realizes spectral analysis.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objects and other advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the specification.
Drawings
For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in the following preferred detail with reference to the accompanying drawings, in which:
FIG. 1 is a schematic diagram of structural units of a GIS equipment mechanical vibration abnormal sound simulation system;
fig. 2 (a) is a schematic structural diagram of a mechanical abnormal sound vibration simulation system of a three-phase independent GIS device, and (b) is a schematic structural diagram of a mechanical abnormal sound vibration simulation system of a three-phase common GIS device;
FIG. 3 is a schematic diagram of the resonant boosting principle;
FIG. 4 is a schematic diagram of a vibration characteristic detection module;
FIG. 5 is a schematic diagram of a specific use flow of a GIS equipment mechanical vibration abnormal sound simulation system;
FIG. 6 is a circuit diagram of a loop wiring of a GIS equipment mechanical vibration abnormal sound simulation system;
FIG. 7 is a graph showing the time and frequency domain waveforms of the vibration signal of the GIS device in the normal state (a) and in the poor contact defect (b) of the isolating switch;
fig. 8 is a time-frequency domain reconstruction waveform of the vibration signal of the GIS device in the normal state (a) and in the poor contact defect (b) of the isolating switch.
Reference numerals: the high-voltage power supply comprises a first test transformer (1), a second test transformer (2), a reactor (3), a first capacitor (4), a high-voltage bushing (5), a circuit breaker (6), an up-converter (7), a third test transformer (8), a second capacitor (9), a console capacitor and an acceleration sensorIsolating switch->Earthing switch->Vibration characteristic detection Module->Upper computer->
Detailed Description
Other advantages and effects of the present invention will become apparent to those skilled in the art from the following disclosure, which describes the embodiments of the present invention with reference to specific examples. The invention may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present invention. It should be noted that the illustrations provided in the following embodiments merely illustrate the basic idea of the present invention by way of illustration, and the following embodiments and features in the embodiments may be combined with each other without conflict.
Wherein the drawings are for illustrative purposes only and are shown in schematic, non-physical, and not intended to limit the invention; for the purpose of better illustrating embodiments of the invention, certain elements of the drawings may be omitted, enlarged or reduced and do not represent the size of the actual product; it will be appreciated by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.
The same or similar reference numbers in the drawings of embodiments of the invention correspond to the same or similar components; in the description of the present invention, it should be understood that, if there are terms such as "upper", "lower", "left", "right", "front", "rear", etc., that indicate an azimuth or a positional relationship based on the azimuth or the positional relationship shown in the drawings, it is only for convenience of describing the present invention and simplifying the description, but not for indicating or suggesting that the referred device or element must have a specific azimuth, be constructed and operated in a specific azimuth, so that the terms describing the positional relationship in the drawings are merely for exemplary illustration and should not be construed as limiting the present invention, and that the specific meaning of the above terms may be understood by those of ordinary skill in the art according to the specific circumstances.
The invention provides a GIS equipment multi-type mechanical vibration abnormal sound defect simulation device and a use method thereof, wherein the defect simulation device mainly comprises a main loop, a vibration abnormal sound defect simulation module, a resonance boosting and induction current rising module and a vibration characteristic detection moduleThe device comprises a measurement and operation control module and a grounding and overcurrent protection module. The defect simulation device can realize breaker, isolating switch and grounding switch>The operation type abnormal sound mechanical defects of the units and the simulation setting of the related periodic abnormal sound defects such as abrasion, fatigue, looseness and the like of the conductive loop and the low-potential loop can be realized, and meanwhile, the vibration characteristic change under the load change can be analyzed. The defect simulation device has flexible and various mechanical vibration abnormal sound defects, is equivalent to actual engineering and has strong practicability.
The GIS equipment multi-type mechanical vibration abnormal sound defect simulation system is shown in figure 1 and comprises a main loop and vibration abnormal sound defect simulation module, a resonance boosting and induction current rising module, a measurement and operation control module, a grounding and overcurrent protection module and a vibration characteristic detection moduleFive parts of the device respectively have the functions of defect simulation, load generation, load display and control, protection, signal detection and the like. The method comprises the following steps:
(1) Main loop and vibration abnormal sound defect simulation module
Main circuit as in fig. 2 (a) and fig. 2 (b) high voltage bushing (5), circuit breaker (6), up-converter (7), acceleration sensorIsolating switch->Earthing switch->And the like. The main loop comprises two structures of independent split type and three-phase integrated type. The method can be used for GIS electromagnetic vibration research under the action of coupling or uncoupling states between phases. Sulfur hexafluoride insulating gas is filled in the loop, the shell is made of demagnetized aluminum alloy materials, and the joint between the shells is supported or fastened by bolts and basin-type insulators. The inner conductor of the loop adopts metallic copper as a conductive material, and a moving contact or a fixed contact is adopted between the conductors for steering and connection. The loop can be externally connected with devices such as a lightning arrester, a voltage transformer, a current transformer and the like, and is internally embedded with parts such as a molecular sieve container and the like. The circuit is supported and isolated from the ground by an insulating support plate. The loop shell is designed with an insulating section, namely, the loop shell is fastened and connected by adopting an insulating bolt, so that the generation of circulation and larger heat loss are avoided.
Specific types of mechanical vibration abnormal sound defects are generally classified into operation type abnormal sound mechanical defects and periodic abnormal sound mechanical defects, and the specific types are as follows:
operation type abnormal sound mechanical defect:
the operation components of the units such as the circuit breaker, the disconnecting switch, the grounding switch and the like are blocked, the operation voltage is too low, and the auxiliary switch is in poor contact.
Periodic abnormal sound mechanical defect:
high potential conductive loop: the contact finger wear difference of the isolating switch, fatigue loosening of a spring, poor contact, loosening of a contact base bolt of a conductor, loosening of an insulator fastening bolt and the like.
Low potential housing and parts: loosening of a shell fastening bolt, unbalanced shell butt joint, loosening of a molecular sieve vessel bolt, loosening of a shielding cover bolt and the like.
(2) Resonant boost and inductive up-current module:
the series resonance boosting module utilizes the L-C series resonance principle to enable the loop to be subjected to the action of alternating high voltage, thereby reducing the capacity requirement of the transformer. Harmonic waveThe vibration step-up module includes, as shown in fig. 2 (a) and 2 (b), a first test transformer (1), a second test transformer (2), a reactor (3), a first capacitor (4), and the like. The piezoelectric resistors are combined by a tuning transformer through a transformer, and can apply 0-220 kV load voltage. When the reactor works, the size of the reactor L is adjusted to enable the reactor L and the capacitor C to generate series resonance under power frequency. At resonance, the voltage U on the loop C And tuning the voltage U on the inductor L As large, U C Is of the magnitude of supply voltage U s A kind of electronic deviceMultiple times. The resonant boosting principle is shown in fig. 3.
The current regulation is performed by using an electromagnetic induction type current booster, and the induction current booster component module is shown in fig. 2 (a) and 2 (b), and comprises a current booster (7), a third test transformer (8), a second capacitor (9) and the like, so that 0-3150A load current can be applied.
(3) Vibration characteristic detection module
Vibration characteristic detection moduleMainly comprises a piezoelectric acceleration sensor>Signal acquisition card, signal conditioner and host computer +.>Four parts are made up as shown in fig. 4. The module firstly carries out intelligent data processing such as A/D conversion, signal conditioning and filtering on the vibration signal of the GIS defect simulation loop, and then transmits the data to an upper computer>Performing modal decomposition and frequency spectrum conversion to further realize feature quantity extraction and mechanical abnormal soundDefect pattern recognition, etc.
(4) Measurement and operation control module:
the operation control module plays roles in measuring, displaying, lifting control and the like of voltage and current signals. The voltage transformer is connected with the voltage transformer and the voltmeter to measure the voltage of the input end, and the voltage divider and the electrostatic voltmeter are used for measuring the voltage output after resonance boosting. The current change of each phase conductor is measured by applying a current transformer to each phase conductor of each loop. The current and the voltage can be controlled in a lifting way through a control console for driving a direct current motor by a key, and are displayed in real time through a digital meter.
(5) Grounding and overcurrent protection module
The system is uniformly grounded, when the air breakdown occurs in the loop due to the over-high voltage of the loop or partial discharge and the like, the working current of the test transformer is greatly increased, and when the current exceeds a set value, the overcurrent protection module automatically cuts off the circuit.
The invention also provides a specific application method of the GIS mechanical abnormal sound simulation system.
The using steps of the mechanical vibration abnormal sound defect simulation device of the multi-type GIS equipment are generally mechanical abnormal sound defect setting, vibration detection module installation, system wiring and loop checking, voltage and current regulation and vibration detection, and the using flow is shown in figure 5.
The first step: multi-type mechanical abnormal sound defect setting:
the GIS mechanical abnormal sound simulation system can realize abnormal simulation of transient vibration caused by operation type mechanical defects and abnormal mechanical vibration caused by fatigue, loose contact failure and the like of components in an operating state. The mechanical abnormal sound defect can be set as a single type defect or a plurality of types of defects at the same time. The general steps for setting defects are:
1) Releasing and storing sulfur hexafluoride gas;
2) Disassembling and hoisting the defect related structural units;
3) Defect setting;
4) Refastening of the defect-related structural units;
5) Sulfur hexafluoride gas is injected into the circuit to a standard pressure level.
The types of mechanical defects common to GIS equipment are generally classified into operation abnormal sound mechanical defects and periodic abnormal sound mechanical defects, and the main component units and the classification of the general defects are shown in table 1.
TABLE 1 Multi-type mechanical abnormal noise defect Classification Table
The defect setting is carried out on three structural units of the isolating switch, the contact seat of the long guide rod and the container of the molecular sieve adsorbent, and the setting method is as follows:
disconnecting switch, namely disassembling the spring of the disconnecting switch and setting the fatigue loosening defect of the spring; disassembling or loosening bolts of a shielding cover of the isolating switch, and setting a loosening defect of the bolts of the shielding cover; and adjusting an operation handle of the isolating switch, adopting a loop resistance meter to be connected in series into a main loop to measure the contact state of the contact finger of the isolating switch, and setting the defect of poor contact of the contact.
And the long guide rod touch seat is used for disassembling or disassembling one or more bolts of the guide rod, which are in contact with the base, and the defect of loosening the bolts of the long guide rod touch seat is overcome.
Molecular sieve vessel: and disassembling or dismantling one or more bolts of the molecular sieve vessel, and setting the loosening defect of the bolts of the molecular sieve vessel.
And a second step of: vibration detection module installation, system wiring and loop inspection
The vibration detection module is installed before the system is wired, the installation base is generally a plastic base without eddy current loss, the base is fixed to the position of the defect equipment by adopting fixing glue, and the signal coupling characteristic between the base and the detection module is improved by using a coupling agent. The module signal wire is sequentially connected with a sensor terminal, detection equipment and a computer at the detection position.
A circuit diagram of the GIS mechanical abnormal sound simulation system is shown in fig. 6, ES represents a grounding switch, DS represents a disconnecting switch, S represents a common switch, CB represents a circuit breaker, LA represents a lightning arrester, TV represents a point voltage transformer, TA represents a current transformer, and BSG represents a high-voltage sleeve. Before the current control loop is connected, whether a power switch is disconnected or not is firstly checked, then single-phase or multi-phase current line connection is carried out according to experimental requirements, and the connection sequence of the current rising circuit is respectively a power supply, a transformer, a capacitor and a current rising device. Before the connection of the voltage control loop, firstly checking whether a voltage protection switch is disconnected, and whether a starting switch is disconnected, and before the connection, firstly performing ground protection, wherein the connection sequence of the resonance voltage regulating circuit is a transformer, a reactor, a capacitor and a high-voltage sleeve. And after the wiring is finished, carrying out loop inspection again to ensure no short circuit and disconnection, and taking down the grounding electrode.
And a third step of: voltage-current continuous regulation and vibration detection
And current and voltage signals are adjusted according to experimental requirements, and single loading or coupling loading of the load is carried out according to the experimental requirements. The rise time of the loop current is generally not too long so as to avoid too high loop temperature rise and thus accelerate equipment aging. The loop is stable, and abnormal sound vibration signal detection is carried out according to experimental requirements. After vibration detection is finished, the current is slowly reduced to 0, then the electric switch is disconnected, and the voltage is the same.
The embodiment provides simulation and detection case analysis of mechanical vibration abnormal sound defects of typical GIS equipment.
The vibration simulation of the poor contact defect of the isolating switch is carried out on the experimental platform by adopting the flow, the load current is set to 2400A, meanwhile, the vibration detection module is adopted for signal detection, processing and characteristic analysis, and the vibration waveform and analysis result of the GIS equipment in a normal state are compared, and the method is concretely as follows:
as can be seen from fig. 7, the frequency spectrum difference between the normal state and the poor contact defect of the isolating switch is quite obvious, the frequency spectrum of the poor contact mechanical defect of the isolating switch is more complex, and the frequency response of the high-frequency region is more obvious. The waveforms of the two signals are processed by a vibration detection module, and then modal decomposition, signal reconstruction, time-frequency conversion and feature extraction are respectively carried out, and the obtained time-frequency waveforms and feature extraction results are shown in fig. 8 and table 2Shown. It can be found that the time-frequency distribution difference between the normal state after time-frequency reconstruction and the defect of poor contact of the isolating switch is more obvious, the periodic defect frequency response is basically avoided in the normal state, the frequency spectrum distribution is more dispersed, and the frequency spectrum distribution of the poor contact of the contact is concentrated and has more obvious amplitude. For the time-frequency signal time-frequency joint entropy(s) 1 ) Maximum two 100Hz wide frequency band frequency values and amplitude (f 1 ，f 1 ，a 1 ，a 2 ) As the characteristic values, the obtained results are shown in table 2, and it was found that the characteristics in terms of frequency response points, time-frequency distribution, energy values, and the like were greatly different. The vibration platform of the system realizes good simulation of GIS mechanical defects and better identification and differentiation of vibration defect states.
TABLE 2 typical characteristic differences between Normal State (a) and disconnector contact failure Defect (b)
Finally, it is noted that the above embodiments are only for illustrating the technical solution of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications and equivalents may be made thereto without departing from the spirit and scope of the present invention, which is intended to be covered by the claims of the present invention.
Claims (10)
1. A GIS equipment mechanical vibration abnormal sound defect simulation system is characterized in that: the device comprises a main loop, a vibration abnormal sound defect simulation module, a resonance boosting and induction current rising module, a vibration characteristic detection module, a measurement and operation control module and a grounding and overcurrent protection module;
the main circuit and the vibration abnormal sound defect simulation module are used for completing defect simulation actions, and comprise a main circuit formed by connecting a circuit breaker, a current booster, a grounding switch, a disconnecting switch and an acceleration sensor, and also comprise a high-voltage sleeve arranged on the circuit breaker, wherein insulating gas is filled in the main circuit, and an insulating supporting plate is used for supporting and isolating the main circuit and the ground;
the resonance boosting and induction current rising module is used for generating a load for the main loop and comprises a resonance boosting part and an induction current rising part; the resonance boosting part comprises a test transformer group, a reactor and a first capacitor, wherein the test transformer group comprises a first test transformer and a second test transformer, the output side of the first test transformer is connected with the input side of the second test transformer, and the output side of the second test transformer is connected with the reactor and the first capacitor; the reactor and the first capacitor generate series resonance under the power frequency, and the resonance boosting part is connected to the high-voltage sleeve; the induction current rising part comprises a power supply, a third test transformer and a second capacitor which are connected in series, and is connected with the current rising device;
the vibration characteristic detection module comprises a piezoelectric acceleration sensor, a signal acquisition card and a signal conditioner which are connected with the upper computer, and is used for carrying out A/D conversion, signal conditioning and filtering treatment on vibration signals of the GIS defect simulation loop, uploading the vibration signals to the upper computer for carrying out modal decomposition and spectrum conversion, and realizing extraction of characteristic quantity and identification of mechanical abnormal sound defect modes;
the measuring and operating control module is used for measuring, displaying and lifting control of the voltage and current signals;
the grounding and overcurrent protection module is used for automatically cutting off a circuit when the current exceeds a set value.
2. The GIS device mechanical vibration abnormal sound defect simulation system according to claim 1, wherein: the main loop and the vibration abnormal sound defect simulation module are independent and split, and comprise three identical main loops, each main loop is provided with a high-voltage sleeve, and each main loop is supported and isolated by an insulating support plate; the high-voltage sleeve of each main loop is connected with the same resonance boosting part in a common way, and the current rising device of each main loop is connected with an induction current rising part respectively.
3. The GIS device mechanical vibration abnormal sound defect simulation system according to claim 1, wherein: the main loop and the vibration abnormal sound defect simulation module are three-phase integrated, only one main loop is arranged, three high-voltage bushings are arranged on the main loop and are jointly connected with the same resonance boosting part, and three induction boosting parts are connected in parallel with a current booster of the main loop.
4. A GIS device mechanical vibration abnormal sound defect simulation system according to any one of claims 2 or 3, wherein: the main loop is internally filled with insulating gas which is sulfur hexafluoride, a demagnetizing aluminum alloy shell is arranged outside the main loop, bolts and basin-type insulators are used for supporting or fastening the shell, a metal copper is used as a conductive material for an inner conductor of the main loop, and a moving contact or a fixed contact is used for steering and connecting the conductor and the conductor.
5. A GIS device mechanical vibration abnormal sound defect simulation system according to any one of claims 2 or 3, wherein: the main loop is also connected with a lightning arrester, a voltage transformer and a current transformer, and a molecular sieve adsorbent container is embedded in the main loop.
6. A GIS device mechanical vibration abnormal sound defect simulation system according to any one of claims 2 or 3, wherein: the measuring and operating control module is used for measuring the voltage of an input end by utilizing a transformer connected with a voltage transformer and a voltmeter, measuring the voltage output after resonance boosting by utilizing a voltage divider and an electrostatic voltmeter, measuring the current change of each phase of wire by externally adding a current transformer to each phase of wire of each main loop, driving a direct current motor to lift and control the current and the voltage by a key of a control console, and displaying in real time by a digital meter.
7. A method for simulating mechanical vibration abnormal sound defects of a GIS device based on the mechanical vibration abnormal sound defect simulation system of the GIS device according to any one of claims 1 to 6, which is characterized by comprising the following steps: the method comprises the following steps:
s1: setting mechanical abnormal sound defects;
s2: vibration characteristic detection module installation, system wiring and loop checking;
s3: voltage current regulation and vibration detection.
8. The method for simulating mechanical vibration abnormal sound defects of GIS equipment according to claim 7, wherein the method comprises the following steps of: the step S1 specifically comprises the following steps:
s11: releasing and storing sulfur hexafluoride gas;
s12: disassembling and hoisting the defect related structural units;
s13: the defect setting comprises defect setting of a disconnecting switch, a long guide rod contact seat and a molecular sieve adsorbent container;
s14: refastening of the defect-related structural units;
s15: sulfur hexafluoride gas is injected into the loop to a standard pressure level;
the isolating switch defect setting comprises the following steps: (1) disassembling a spring of the isolating switch, and setting a spring fatigue loosening defect; (2) disassembling or loosening bolts of a shielding cover of the isolating switch, and setting a loosening defect of the bolts of the shielding cover; (3) adjusting an operation handle of the isolating switch, and adopting a loop resistance meter; (4) the method comprises the steps of connecting a main loop in series to measure the contact state of a contact finger of an isolating switch, and setting the defect of poor contact of a contact;
the defect setting of the long guide rod contact seat comprises the following steps: loosening or disassembling one or more bolts of the guide rod, which are in contact with the base, and setting the loosening defect of the bolts of the long guide rod contact base;
the molecular sieve adsorbent vessel defect placement includes: and disassembling or dismantling one or more bolts of the molecular sieve vessel, and setting the loosening defect of the bolts of the molecular sieve vessel.
9. The method for simulating mechanical vibration abnormal sound defects of GIS equipment according to claim 7, wherein the method comprises the following steps of: the step S2 specifically includes the following steps:
s21: the vibration characteristic detection module is installed, the installation base is a plastic base without eddy current loss, the base is fixed to the position of the defect equipment, the coupling agent is used for improving the signal coupling characteristic between the base and the vibration characteristic detection module, and the module signal wire is sequentially connected with a sensor terminal, detection equipment and an upper computer at the detection position;
s22: a system wiring connected to form the GIS equipment mechanical vibration abnormal sound defect simulation system as set forth in any one of claims 1-6;
s23: and after the wiring is finished, carrying out loop inspection again to ensure no short circuit and disconnection, and taking down the grounding electrode.
10. The method for simulating mechanical vibration abnormal sound defects of GIS equipment according to claim 7, wherein the method comprises the following steps of: the step S3 specifically comprises the following steps:
s31: adjusting current and voltage signals to carry out single loading or coupling loading of a load;
s32: detecting abnormal sound vibration signals;
s33: after vibration detection is finished, the current and the voltage are slowly reduced to 0, and then the electric switch is disconnected.
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