CN111123056A - On-load voltage regulating switch short circuit electrical safety detection device and detection method - Google Patents
On-load voltage regulating switch short circuit electrical safety detection device and detection method Download PDFInfo
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- CN111123056A CN111123056A CN201911352505.3A CN201911352505A CN111123056A CN 111123056 A CN111123056 A CN 111123056A CN 201911352505 A CN201911352505 A CN 201911352505A CN 111123056 A CN111123056 A CN 111123056A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
- G01R31/16—Construction of testing vessels; Electrodes therefor
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
- G01R31/1218—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 optical methods; using charged particle, e.g. electron, beams or X-rays
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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
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
- G01R31/3271—Testing of circuit interrupters, switches or circuit-breakers of high voltage or medium voltage devices
- G01R31/3272—Apparatus, systems or circuits therefor
- G01R31/3274—Details related to measuring, e.g. sensing, displaying or computing; Measuring of variables related to the contact pieces, e.g. wear, position or resistance
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Abstract
The invention provides a short circuit electrical safety detection device for an on-load voltage regulating switch, which comprises: the device comprises a test oil tank, a test sleeve, an electrode, a pressure release valve, an insulating flange, an optical fiber sensor and a mechanical sensor; the test sleeve is fixed on one side of the test oil tank and used for providing required short-circuit current and maintaining certain arc discharge voltage; one end of the electrode is connected with the tail part of the test sleeve, and the other end of the electrode is grounded; the pressure release valve is arranged on the test oil tank; the insulating flange is arranged in the test oil tank and used for simulating an insulating partition plate; the optical fiber sensor and the mechanical sensor are arranged on the insulating flange and the test oil tank and used for measuring displacement, strain and pressure of corresponding measuring points. The detection device provided by the invention can detect whether the pressure relief valve can be accurately, quickly and safely started or not and whether the mechanical strength of the insulating flange is enough or not.
Description
Technical Field
The invention belongs to the technical field of detection, and particularly relates to a short-circuit electrical safety detection device and a detection method for an on-load voltage regulating switch.
Background
At present, according to the requirements of extra-high voltage direct current engineering construction, an on-load tap changer is arranged externally, namely, the on-load tap changer is arranged in an independent switch oil tank, the switch oil tank and a main body oil tank are isolated by a laminated insulation board (Weidman scheme) or other materials (such as epoxy boards and the like), and meanwhile, the electrical insulation strength and the mechanical strength of the switch oil tank and the main body oil tank are required to be ensured. Meanwhile, according to preliminary calculation in the early stage, in view of discharge energy and generated pressure under the condition that the on-load tap changer has an interstage short circuit, a pressure relief valve must be arranged on a switch oil tank so as to perform corresponding pressure relief release when huge pressure is generated in the switch, and therefore the corresponding protection purpose is achieved.
Due to the fact that the cost of the single oil tank of the on-load voltage-regulating switch of the converter transformer is high, the performance of the single oil tank of the on-load voltage-regulating switch of the converter transformer cannot be verified in the prior art.
Disclosure of Invention
Aiming at the defects, the invention provides the on-load tap changer short circuit electrical safety detection equipment and system which can detect whether the pressure relief valve can be accurately and quickly started safely and whether the mechanical strength of the insulating partition plate is enough when the pressure relief valve acts.
The invention provides the following technical scheme: an on-load tap changer short circuit electrical safety detection device, comprising: the device comprises a test oil tank, a test sleeve, an electrode, a pressure release valve, an insulating flange, an optical fiber sensor and a mechanical sensor;
the test sleeve is fixed on one side of the test oil tank and used for providing required short-circuit current and maintaining certain arc discharge voltage;
one end of the electrode is connected with the tail part of the test sleeve, and the other end of the electrode is grounded;
the pressure release valve is arranged on the test oil tank;
the insulating flange is arranged in the test oil tank and used for simulating an insulating partition plate;
the optical fiber sensor and the mechanical sensor are arranged on the insulating flange and the test oil tank and used for measuring displacement, strain and pressure of corresponding measuring points.
Preferably, the device further comprises a lifting seat;
the lifting seat is fixed on the side surface of the test oil tank;
the test sleeve is mounted on the lifting seat.
Preferably, the device further comprises a ground sleeve; the grounding sleeve is positioned at the bottom of the test oil tank, and a certain distance is reserved between the grounding sleeve and the electrode for maintaining a discharge gap.
Preferably, the grounding sleeve is a matched dry sleeve.
Preferably, the device further comprises a transition flange;
the insulating flange is assembled on the transition flange firstly and then reversely installed on the test oil tank.
Preferably, the apparatus further comprises a process valve;
the process valve is arranged at the lower part of the test oil tank and is used for carrying out oil filling and oil discharging process operation on the whole test device.
Preferably, the process valve adopts a DN50 brass flanged gate valve.
Preferably, a mounting hole is reserved in the lower portion of the test oil tank.
Preferably, the pressure relief valve is installed at an upper portion or a lower portion of the test tank.
Preferably, the optical fiber sensor comprises an optical fiber pressure sensor and an optical fiber strain sensor.
Preferably, the mechanical sensor includes: mechanical pressure transmitter, mechanical displacement sensor and resistance strain gauge.
An on-load tap changer short circuit electrical safety detection method, the method comprising:
the test sleeve fixed on one side of the test oil tank provides required short-circuit current and maintains certain arc discharge voltage, and is grounded through an electrode connected to the tail part of the test sleeve;
observing whether a pressure relief valve installed on the test oil tank can be accurately, quickly and safely started;
and measuring the displacement, strain and pressure of the insulating flange for simulating the insulating partition plate by using an optical fiber sensor and a mechanical sensor which are arranged on the insulating flange and the test oil tank.
Preferably, the test sleeve fixed on one side of the test tank provides required short-circuit current and maintains a certain arc discharge voltage, and the method comprises the following steps:
a test voltage of about 44kV, a short-circuit current with an effective value of 30kA, is applied to the test bushing mounted on a raised seat fixed to the side of the test tank, maintaining its duration for at least 85ms and 220ms, respectively.
The invention has the beneficial effects that:
the invention provides a short circuit electrical safety detection device for an on-load tap changer, which comprises: the device comprises a test oil tank, a test sleeve, an electrode, a pressure release valve, an insulating flange, an optical fiber sensor and a mechanical sensor; the test sleeve is fixed on one side of the test oil tank and used for providing required short-circuit current and maintaining certain arc discharge voltage; one end of the electrode is connected with the tail part of the test sleeve, and the other end of the electrode is grounded; the pressure release valve is arranged on the test oil tank; the insulating flange is arranged in the test oil tank and used for simulating an insulating partition plate; the optical fiber sensor and the mechanical sensor are arranged on the insulating flange and the test oil tank and used for measuring displacement, strain and pressure of corresponding measuring points. The discharge of the test oil tank in the use process and the additional installation of the pressure relief valve are detected safely, and the electrical insulation strength and the mechanical strength of the insulation flange are ensured, so that the corresponding protection purpose is achieved.
The electrical detection system provided by the invention adopts two types of sensors, namely an optical fiber type sensor and a mechanical type sensor, and adopts optical fiber for long-distance transmission after converting into optical signals, so that the attenuation in the signal transmission process is reduced and guaranteed. System redundancy is increased and a comparative analysis of the two types of sensor signals is possible.
Drawings
Fig. 1 is a schematic diagram of an on-load tap changer short circuit electrical safety detection device provided by the invention;
FIG. 2 is a three-dimensional side perspective view of an on-load tap changer short circuit electrical safety detection device provided by the present invention;
fig. 3 is a top view of an insulating flange of the on-load tap changer short circuit electrical safety detection device provided by the invention;
fig. 4 is a wiring diagram of the on-load tap changer short circuit electrical safety detection system provided by the invention;
the device comprises a test oil tank 1, a test sleeve 2, a lifting seat 2-1, a test sleeve connecting end 2-2 on the upper portion, a test sleeve connecting end 2-3 on the lower portion, a grounding sleeve 3, a pressure release valve 4, an insulating flange 5, a first fixing screw rod 5-1, a transition flange 6, a second fixing screw rod 6-1, a box cover 7 and a process valve 8.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
As shown in fig. 1-2, the short-circuit electrical safety detection device for an on-load tap changer provided by the invention comprises a test oil tank 1 filled with transformer oil, a test sleeve 2 serving as an anode for applying short circuit, a grounding sleeve 3 serving as a cathode, a pressure relief valve 4 arranged at the upper part of the test oil tank, an insulating flange 5 arranged at the upper part inside the test oil tank, a transition flange 6, a tank cover 7, and a process valve 8 arranged at the lower part of the side part of the oil tank and used for process operation; the test sleeve 2 is arranged on the side wall of the test oil tank and is transversely led out, the insulating flange 5 is fixedly connected below the transition flange 6 through a first fixing screw 5-1, and the transition flange 6 is fixedly connected above the tank cover 7 through a second fixing screw 6-1.
The test oil tank 1 is of a circular structure formed by welding high-strength steel plates, the side wall of the test oil tank 1 is provided with a lifting seat 2-1 which is used for fixedly connecting a test sleeve 2 and has the inner diameter of 500mm and the wall thickness of 6mm, the diameter of the inner wall of the test oil tank 1 is 3000mm, the wall thickness of 16mm and the height of the test oil tank is 2000 mm.
The test sleeve 2 is a dry porcelain sleeve with a western electric glue impregnated paper, and has a voltage level of 126kV (25 times of rated current) and allows a dynamic stabilization current of 156.25kA (2.5 times of thermal stabilization current).
The upper test sleeve connecting end 2-2 is a stainless steel rod with the diameter of 30mm and used as an anode, is bent in an L shape and is fixedly connected with the test sleeve 2 through a lifting seat 2-1, so that the test sleeve is ensured not to displace under the action of large electric force during test, and the stainless steel rod electrode of the upper test sleeve connecting end 2-2 is connected with an external anode power supply through the test sleeve; the lower grounding test sleeve connecting end 2-3 is a stainless steel bar with the diameter of 30mm and used as a cathode, and is fixedly connected with the grounding sleeve 3 through a screw; an oil gap of 0.5mm is formed between the upper test casing connecting end 2-2 and the lower grounding test casing connecting end 2-3.
The grounding sleeve 3 is a matched dry sleeve, and the connecting end 2-3 of the lower grounding sleeve is led out to be grounded.
As shown in fig. 3, the insulation flange 5 is made of laminated insulation paperboard T4, and has a thickness of 90mm and a diameter of 1200 mm; the first fixed screw rods are uniformly distributed at a distance from the circle center of the insulating flange, the center distance of the openings is 1140mm, the number of the first screw rods is 36, and the hole depth is 50 mm.
Example 2
This example differs from example 1 only in that the diameter of the upper test bushing connection end 2-2 of the stainless steel rod as the anode and the lower ground test bushing connection end 2-3 of the stainless steel rod as the cathode were 30mm, and the oil gap between the upper test bushing connection end 2-2 and the lower ground test bushing connection end 2-3 was 10 mm.
Example 3
This example differs from examples 1 and 2 only in that the upper test bushing connection end 2-2 of the stainless steel rod as anode and the lower ground test bushing connection end 2-3 of the stainless steel rod as cathode have a diameter of 30mm and the oil gap between the upper test bushing connection end 2-2 and the lower ground test bushing connection end 2-3 is 20 mm.
Example 4
The invention also provides a method for detecting the electrical safety of the short circuit of the on-load tap changer based on the same inventive concept, which comprises the following steps:
the test sleeve fixed on one side of the test oil tank provides required short-circuit current and maintains certain arc discharge voltage, and is grounded through an electrode connected to the tail part of the test sleeve;
observing whether a pressure relief valve installed on the test oil tank can be accurately, quickly and safely started;
and measuring the displacement, strain and pressure of the insulating flange for simulating the insulating partition plate by using an optical fiber sensor and a mechanical sensor which are arranged on the insulating flange and the test oil tank.
Preferably, the test sleeve fixed on one side of the test tank provides required short-circuit current and maintains a certain arc discharge voltage, and the method comprises the following steps:
a test voltage of about 44kV, a short-circuit current with an effective value of 30kA, is applied to the test bushing mounted on a raised seat fixed to the side of the test tank, maintaining its duration for at least 85ms and 220ms, respectively.
Observing whether a pressure relief valve installed on the test oil tank can be accurately, quickly and safely started;
and measuring the displacement, strain and pressure of the insulating flange for simulating the insulating partition plate by using an optical fiber sensor and a mechanical sensor which are arranged on the insulating flange and the test oil tank.
While the invention has been described with reference to a preferred embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In particular, the technical features mentioned in the embodiments can be combined in any way as long as there is no structural conflict. It is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.
The embodiment is only an example of the present invention, and not an exclusive embodiment, and it will be apparent to those skilled in the art that appropriate substitutions or modifications may be made without departing from the scope of the present invention, and will fall within the scope of the present invention.
It is to be noted that, unless otherwise specified, technical or scientific terms used herein shall have the ordinary meaning as understood by those skilled in the art to which the present invention belongs.
In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.
Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.
Claims (13)
1. The utility model provides an on-load tap-changer short circuit electrical safety detection device which characterized in that includes: the device comprises a test oil tank, a test sleeve, an electrode, a pressure release valve, an insulating flange, an optical fiber sensor and a mechanical sensor;
the test sleeve is fixed on one side of the test oil tank and used for providing required short-circuit current and maintaining certain arc discharge voltage;
one end of the electrode is connected with the tail part of the test sleeve, and the other end of the electrode is grounded;
the pressure release valve is arranged on the test oil tank;
the insulating flange is arranged in the test oil tank and used for simulating an insulating partition plate;
the optical fiber sensor and the mechanical sensor are arranged on the insulating flange and the test oil tank and used for measuring displacement, strain and pressure of corresponding measuring points.
2. The device of claim 1, further comprising a lifting seat;
the lifting seat is fixed on the side surface of the test oil tank;
the test sleeve is mounted on the lifting seat.
3. The apparatus of claim 1, further comprising a ground sleeve; the grounding sleeve is positioned at the bottom of the test oil tank, and a certain distance is reserved between the grounding sleeve and the electrode for maintaining a discharge gap.
4. The apparatus of claim 3, wherein the grounding sleeve is a mating dry sleeve.
5. The apparatus of claim 1, further comprising a transition flange;
the insulating flange is assembled on the transition flange firstly and then reversely installed on the test oil tank.
6. The apparatus of claim 1, further comprising a process valve;
the process valve is arranged at the lower part of the test oil tank and is used for carrying out oil filling and oil discharging process operation on the whole test device.
7. The apparatus of claim 6, wherein the process valve is a DN50 brass flanged gate valve.
8. The device of claim 1, wherein the lower part of the test oil tank is reserved with a mounting hole.
9. The apparatus of claim 1, wherein the pressure relief valve is mounted at an upper or lower portion of the test tank.
10. The apparatus of claim 1, wherein the fiber optic sensor comprises a fiber optic pressure sensor and a fiber optic strain sensor.
11. The apparatus of claim 1, wherein the mechanical sensor comprises: mechanical pressure transmitter, mechanical displacement sensor and resistance strain gauge.
12. An on-load tap changer short circuit electrical safety detection method is characterized by comprising the following steps:
the test sleeve fixed on one side of the test oil tank provides required short-circuit current and maintains certain arc discharge voltage, and is grounded through an electrode connected to the tail part of the test sleeve;
observing whether a pressure relief valve installed on the test oil tank can be accurately, quickly and safely started;
and measuring the displacement, strain and pressure of the insulating flange for simulating the insulating partition plate by using an optical fiber sensor and a mechanical sensor which are arranged on the insulating flange and the test oil tank.
13. The method of claim 12, wherein said providing a desired short circuit current and maintaining a certain arc discharge voltage by a test bushing secured to one side of a test tank comprises:
a test voltage of about 44kV, a short-circuit current with an effective value of 30kA, is applied to the test bushing mounted on a raised seat fixed to the side of the test tank, maintaining its duration for at least 85ms and 220ms, respectively.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911352505.3A CN111123056A (en) | 2019-12-25 | 2019-12-25 | On-load voltage regulating switch short circuit electrical safety detection device and detection method |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911352505.3A CN111123056A (en) | 2019-12-25 | 2019-12-25 | On-load voltage regulating switch short circuit electrical safety detection device and detection method |
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| CN111123056A true CN111123056A (en) | 2020-05-08 |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111999613A (en) * | 2020-08-17 | 2020-11-27 | 国家电网有限公司 | Device and system for simulating arc discharge in oil by using transformer and test method thereof |
| CN112630643A (en) * | 2020-12-14 | 2021-04-09 | 国网经济技术研究院有限公司 | Converter transformer on-load voltage regulation switch top cover state monitoring device and method |
| CN112635214A (en) * | 2020-12-14 | 2021-04-09 | 西安交通大学 | Device and method for protecting deformation of top cover of converter transformer on-load voltage regulation switch |
| CN112816232A (en) * | 2020-12-31 | 2021-05-18 | 北京中瑞和电气有限公司 | Arc discharge explosion-proof test device in on-load tap-changer oil |
| CN112986811A (en) * | 2021-02-08 | 2021-06-18 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | Testing device and method for converter transformer tap switch top cover pressure-bearing limit arc test |
| CN112986812A (en) * | 2021-02-08 | 2021-06-18 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | High-energy arc short-circuit fault test simulation device and method for tap changer |
| CN114295971A (en) * | 2021-12-30 | 2022-04-08 | 国网河北省电力有限公司电力科学研究院 | On-load tap-changer state detection device and method and control equipment |
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2019
- 2019-12-25 CN CN201911352505.3A patent/CN111123056A/en active Pending
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111999613A (en) * | 2020-08-17 | 2020-11-27 | 国家电网有限公司 | Device and system for simulating arc discharge in oil by using transformer and test method thereof |
| CN112630643A (en) * | 2020-12-14 | 2021-04-09 | 国网经济技术研究院有限公司 | Converter transformer on-load voltage regulation switch top cover state monitoring device and method |
| CN112635214A (en) * | 2020-12-14 | 2021-04-09 | 西安交通大学 | Device and method for protecting deformation of top cover of converter transformer on-load voltage regulation switch |
| CN112635214B (en) * | 2020-12-14 | 2022-05-20 | 西安交通大学 | Converter transformer on-load voltage regulation switch top cover deformation protection device and method |
| CN112816232A (en) * | 2020-12-31 | 2021-05-18 | 北京中瑞和电气有限公司 | Arc discharge explosion-proof test device in on-load tap-changer oil |
| CN112986811A (en) * | 2021-02-08 | 2021-06-18 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | Testing device and method for converter transformer tap switch top cover pressure-bearing limit arc test |
| CN112986812A (en) * | 2021-02-08 | 2021-06-18 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | High-energy arc short-circuit fault test simulation device and method for tap changer |
| CN114295971A (en) * | 2021-12-30 | 2022-04-08 | 国网河北省电力有限公司电力科学研究院 | On-load tap-changer state detection device and method and control equipment |
| CN114295971B (en) * | 2021-12-30 | 2024-05-28 | 国网河北省电力有限公司电力科学研究院 | On-load tap-changer state detection device, method and control equipment |
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