Insulation structure for electrical test of power transformer
By designing a dynamic and variable monitoring mechanism in the power transformer system, the vibration and deformation of the corrugated pipe is monitored in real time, the problems of misalignment at both ends of the corrugated pipe and difficulty in monitoring the vibration in the middle are solved, and the accuracy and reliability of the insulation test are improved.
Patent Information
- Application Number
- CN202420701690.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-08
- Publication Date
- 2025-05-27
- Estimated Expiration
- 2034-04-08
AI Technical Summary
In the insulation test of power transformer systems, the misalignment at both ends of the bellows and the vibration in the middle are difficult to monitor in real time, which affects the sealing and the accuracy of the test results.
An electrical test insulation structure is designed to monitor the vibration and deformation of the bellows in real time through a dynamic and variable monitoring mechanism, including a laser rangefinder and vibration sensor, to ensure accurate monitoring of the misalignment at both ends of the bellows and the vibration in the pipeline area.
Real-time monitoring of the dislocation conditions at both ends of the bellows and vibration conditions in the pipeline area is achieved, the accuracy and reliability of insulation tests are improved, and the stability and sealing of the transformer system are ensured.
Smart Images
Figure CN222913732U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the field of electrical equipment tests in power systems, and particularly relates to an electrical test insulation structure for a power transformer. Background Technique
[0002] GIS and transformers are generally connected by overhead lines. According to the geographical environment of the substation and the GIS structure form, it is also often the case that GIS and transformers are directly connected through bus ducts. In the insulation test of the transformer system after on-site installation, in addition to the insulation test between the GIS and the transformer shell, the insulation test at the connection between the GIS bus duct and the bus duct GIL of the pipeline is also required.
[0003] For the connection between the GIS bus duct and the bus duct GIL of the pipeline, between the GIS-side shells and between the GIL-side shells, sealed and fixed pot-type insulators are used, and the GIS-side and GIL-side conductors are connected through the pot-type insulators. The GIS-side conductor and the GIL-side conductor are interconnected through a separable conductor. Generally, in addition to setting bellows at the direct connection part between the GIS shell and the transformer, bellows are also required to be set between the GIS-side shell and the GIL-side shell; the reason is that: the transformer will generate vibrations during operation, and GIS and GIL are generally supplied by two suppliers, and there are errors during the installation process. The bellows can adjust the direction of the butt joint within the elastic bending range, which can not only absorb the vibrations generated during the operation of the transformer, but also overcome the situation when the GIS-side shell and the GIL-side shell are not aligned.
[0004] Before the insulation test process, SF 6 gas is injected into the GIL-side shell and the bellows. After completion, the transformer is switched on and operated for the insulation test. During the detection of the insulation properties of each shell surface, the seal detection of the shell connection is also required. Usually, the test time is 25 days, and various insulation data are recorded.
[0005] Since the connection between the GIS bus duct and the bus duct GIL of the pipeline uses bellows for transition connection, and there is a certain amplitude of vibration on the bellows due to the vibration generated during the operation of the transformer; under the influence of this inevitable vibration, there will inevitably be a certain amount of misalignment between the GIS bus duct and the bus duct GIL of the pipeline; this situation also poses a certain test to the connection tightness between the shells.
[0006] Therefore, it is necessary to set up an electrical test insulation structure that can monitor the misalignment of both ends of the bellows and the vibration of the middle part of the bellows in real time. Content of the Utility Model
[0007] The purpose of the present utility model is to provide an electrical test insulation structure for a power transformer. The technical problem to be solved is to provide an electrical test insulation structure that can monitor the misalignment at both ends of the bellows and the vibration at the middle part of the bellows in real time.
[0008] To achieve the above object, the present utility model provides the following technical solution: An electrical test insulation structure for a power transformer, including a GIS-side housing, a GIS-side pot-type insulator sealingly connected to one end of the GIS-side housing, GIS-side conductors respectively connected to both ends of the central power connection head of the GIS-side pot-type insulator, a bellows sealingly connected to one end of the GIS-side housing, several sections of GIL-side housings sealingly connected to one end of the bellows, the GIS-side conductor passing through the bellows to the GIL-side housing and connected to one end of the GIL-side conductor through a separable conductor, GIL-side pot-type insulators sealingly connected between the GIL-side housings, and the GIL-side conductor passing through to the inside of the GIL-side housing and connected to each other through the central power connection head of the GIL-side pot-type insulator;
[0009] Both the GIS-side housing and the GIL-side housing are supported and fixed on the ground through support members. A fixed frame two is provided on the GIL-side housing near the bellows. A connecting plate one is connected to the fixed frame two through a support frame, and a dynamic change monitoring mechanism is provided on the connecting plate one. The dynamic change monitoring mechanism is used to monitor the vibration and deformation dynamics of the bellows in real time.
[0010] To stabilize the GIS-side housing and the GIL-side housing during the transformer test, preferably, the support member includes a fixed frame one respectively fixedly sleeved on the GIS-side housing and the GIL-side housing. A support column is connected to the bottom of the fixed frame one, and a base is connected to the bottom of the support column. Both sides of the base are fixed on the ground through expansion bolts.
[0011] To facilitate adding SF 6 gas into the middle GIL-side housing and the bellows during the electrical test and facilitate sampling of SF 6 gas after the test, preferably, one side of the top of the GIL-side housing is connected to a pressure relief valve through a connecting pipe one. The discharge end of the pressure relief valve is connected to a discharge pipe through a through connecting pipe. The discharge pipe is used to discharge SF 6 gas in the middle GIL-side housing and the bellows;
[0012] The bottom of the GIL-side housing is connected to a three-way through a connecting pipe two. One side end of the three-way is connected to a gas filling nozzle through a one-way valve. The gas filling nozzle is used to add SF 6 gas into the middle GIL-side housing and the bellows through an external SF 6 gas tank.
[0013] In order to facilitate the monitoring of the SF added during the electrical test 6 pressure, preferably, the other end of the tee is connected with a pressure detector through a lead pipe, and the pressure detector is used to monitor the SF in the middle GIL side housing and the bellows in real time 6 gas pressure.
[0014] In order to monitor the movement conditions on both sides of the bellows, preferably, the movement change monitoring mechanism includes laser rangefinders arranged on both sides of the first connecting plate, and reflective sheets are arranged at the shooting heads of the laser rangefinders facing the tops of both sides of the bellows;
[0015] A vibration sensor is arranged in the area of the first connecting plate between the laser rangefinders, and the vibration sensor is used to monitor the vibration condition of the pipe part of the bellows in real time.
[0016] In order to better contact the vibration sensor with the pipe of the bellows and monitor the vibration condition of its pipe part, preferably, a sliding rod is slidably arranged on the first connecting plate, one side of the top of the sliding rod is connected with a second connecting plate, and a lead screw is screwed in the second connecting plate and one end of the lead screw is rotatably arranged on the first connecting plate;
[0017] The bottom of the sliding rod is connected with a spring through a connecting bottom, the bottom of the spring is connected with a contact plate, and a vibration sensor is arranged on the contact plate.
[0018] Compared with the prior art, the beneficial effects of the present utility model are:
[0019] The electrical test insulation structure of the power transformer involved in the present utility model forms a closed pipe section between the bellows and the GIL side housing through the isolation of the pot-type insulators on both sides, providing conditions for segmented insulation monitoring. During the actual test process, it is not only convenient for installers or testers to master the SF in the middle GIL side housing and the bellows 6 gas pressure value, but also through the setting of the movement change monitoring mechanism, the dislocation conditions at both ends of the bellows and the vibration conditions in the bellows pipeline area can be monitored. Description of the Drawings
[0020] Figure 1 is the front view schematic diagram of the present utility model;
[0021] Figure 2 is Figure 1 the partial sectional view of;
[0022] Figure 3 is Figure 2 the connection schematic diagram of the monitoring frame in.
[0023] In the figure: 1 GIS-side housing, 2 GIS-side pot insulator, 3 GIS-side conductor, 4 bellows, 5 GIL-side pot insulator, 6 GIL-side housing, 7 split conductor, 8 GIL-side conductor, 9 fixing frame 1, 10 support column, 11 base, 12 relief valve, 13 drain pipe, 14 tee, 15 check valve, 16 gas filling nozzle, 17 lead pipe, 18 air pressure detector, 19 fixing frame 2, 20 support frame, 21 connecting plate 1, 22 laser rangefinder, 23 sliding rod, 24 connecting plate 2, 25 lead screw, 26 connecting bottom, 27 spring, 28 release plate, 29 vibration sensor. Specific implementation mode
[0024] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention.
[0025] Refer to Figure 1 and Figure 2 As shown, the embodiment of the present invention provides an insulation structure for electrical tests of a power transformer, including a GIS-side housing 1, a GIS-side pot insulator 2 flange-sealed and connected to the left end of the GIS-side housing 1, GIS-side conductors 3 respectively connected to both ends of the central electrical connection head of the GIS-side pot insulator 2, a bellows 4 flange-sealed and connected to the left end of the GIS-side housing 1, several sections of GIL-side housings 6 flange-sealed and connected to the right end of the bellows 4, the GIS-side conductor 3 passing through the bellows 4 to the GIL-side housing 6 and connected to the right end of the GIL-side conductor 8 through a split conductor 7, GIL-side pot insulators 5 being hermetically connected between the GIL-side housings 6, and the GIL-side conductor 8 passing through to the inside of the GIL-side housing 6 and being interconnected through the central electrical connection heads of the GIL-side pot insulators 5;
[0026] Therefore, in this insulation electrical layout, through the isolation of the pot insulators on both sides, a closed pipe section is formed by the bellows 4 and the GIL-side housing 6. When SF 6 gas is injected into the bellows 4 and the GIL-side housing 6, a segmented insulation effect can be achieved.
[0027] Refer to Figure 1 , Figure 2 and Figure 3 , both the GIS-side housing 1 and the GIL-side housing 6 are supported and fixed on the ground through support members. Bolts are used to lock and fix both ends of the upper and lower fixing frames 2 at the GIL-side housing 6 near the bellows 4, so that the fixing frame 2 is stably installed on the GIL-side housing 6. A support frame 20 is bolt-fixed to the top of the fixing frame 2. The support frame 20 is an L-shaped column structure. A connecting plate 1 is bolt-fixed to the right end of the support frame 20. A dynamic change monitoring mechanism is arranged on the connecting plate 1. The dynamic change monitoring mechanism is used to monitor the vibration and deformation dynamics of the bellows 4 in real time.
[0028] By setting up the dynamic change monitoring mechanism, it is possible to monitor the dislocation situation at both ends of the corrugated pipe 4 and the vibration situation in the corrugated pipe pipeline area.
[0029] Refer to Figure 1 and Figure 2 As shown in FIGS. and, the support member includes a first fixed frame 9 respectively and fixedly sleeved on the GIS side housing 1 and the GIL side housing 6. The first fixed frame 9 is a structure of two arc-shaped plates locked by bolts at the front and rear parts. The first fixed frame 9 is stably installed on the GIS side housing 1 and the GIL side housing 6. The bottom flange of the first fixed frame 9 is connected with a support column 10, and the bottom of the support column 10 is welded with a base 11. The left and right sides of the base 11 are respectively fixed on the concrete floor through expansion bolts.
[0030] The setting of the support member is used to provide ground support for the connection area between the GIS and the GIL busbars, and reduce the influence on the connection parts of the lines and pipelines in both areas caused by the vibration during the operation of the transformer.
[0031] Refer to Figure 1 and Figure 2 As shown in FIGS. and, a first connecting pipe is integrally provided on the left side of the top of the GIL side housing 6. The top of the first connecting pipe is screwed with the inlet end of the air release valve 12. The discharge end of the air release valve 12 is screwed with a through connecting pipe. An exhaust pipe 13 is press-fitted on the through connecting pipe. The press-fitted part of the exhaust pipe 13 and the through connecting pipe is also fastened with a hose clamp. The exhaust pipe 13 is a rubber exhaust hose, and the exhaust pipe 13 is used to discharge SF 6 gas;
[0032] When it is necessary to discharge some SF 6 gas in the middle GIL side housing 6 and the corrugated pipe 4, the air release valve 12 can be opened, and the SF 6 gas in the middle GIL side housing 6 and the corrugated pipe 4 is discharged through the exhaust pipe 13; under such a setting, it is also convenient to sample the SF 6 gas in the middle GIL side housing 6 and the corrugated pipe 4 that has been in operation for a period of time, so as to facilitate the detection of the moisture content of the SF 6 gas.
[0033] Refer to Figure 1 and Figure 2 As shown in FIGS. and, a second connecting pipe is integrally provided at the bottom of the GIL side housing 6. A three-way joint 14 is screwed on the second connecting pipe. The side end of the three-way joint 14 is connected with a one-way valve 15 by threading, and the inlet end of the one-way valve 15 is connected with a gas filling nozzle 16 by threading. The gas filling nozzle 16 is used for adding SF 6 gas into the middle GIL side housing 6 and the corrugated pipe 4 through an external SF 6 gas cylinder. When filling gas, after the filling head of the external SF 6 gas cylinder is connected to the gas filling nozzle 16, open the SF 6The gas valve of the gas cylinder can inject SF into the middle GIL side housing 6 and the bellows 4. 6 gas.
[0034] The left end of the tee 14 is connected by threaded connection with a lead pipe 17. The lower end of the lead pipe 17 is connected to the gas access end of the air pressure detector 18. The air pressure detector 18 is used to monitor the SF gas pressure in the middle GIL side housing 6 and the bellows 4 in real time. 6 gas pressure.
[0035] Thus, with the help of the air pressure detector 18, it is convenient for installers or testers to master the SF gas pressure value in the middle GIL side housing 6 and the bellows 4, providing good assistance during the gas filling process and the long-term gas pressure data recording process. 6 gas pressure value, providing good assistance during the gas filling process and the long-term gas pressure data recording process.
[0036] Refer to Figure 1 、 Figure 2 and Figure 3 The dynamic change monitoring mechanism includes laser rangefinders 22 screwed on the left and right sides of the connecting plate one 21. The transmission lines of the laser rangefinders 22 are connected to the signal access end of an external computer and reach a data transmission protocol with the external computer. Therefore, through the external computer, the distance values obtained on both sides of the bellows 4 can be viewed in real time. Reflective sheets are pasted on the tops of both sides of the bellows 4 opposite to the emitting heads of the laser rangefinders 22. Both sides of the bellows 4 are circular, and the reflective sheets are arc-shaped.
[0037] Therefore, when the GIL side housing 6 and the GIS side housing 1 on both sides of the bellows 4 are misaligned, the distance values obtained by one side or both sides of the laser rangefinders 22 change. The change values of the distances before and after can be recorded through the external computer, which can reflect the misalignment situation of the GIL side housing 6 and the GIS side housing 1 caused by the vibration of the transformer during operation.
[0038] A vibration sensor 29 is arranged in the area on the connecting plate one 21 and between the laser rangefinders 22. The transmission line of the vibration sensor 29 is connected to the external computer by a vibration data transmitter and reaches a data transmission protocol with the external computer. The vibration situation in the pipe area of the bellows 4 is recorded in real time through the external computer, which is beneficial for the staff to analyze the vibration changes at different times. The vibration sensor 29 is used to monitor the vibration situation of the pipe part of the bellows 4 in real time.
[0039] Refer to Figure 1 、 Figure 2 and Figure 3 More specifically, a sliding rod 23 is slidably inserted into the connecting plate one 21. A connecting plate two 24 is fixed by screws on the right side of the top of the sliding rod 23. A lead screw 25 is screwed into the connecting plate two 24. A connecting shaft is integrally arranged at the center position of the lower end of the lead screw 25. A bearing groove is provided on the right side of the connecting plate one 21. A bearing is press-fitted into the bearing groove, and the inner ring of the bearing is press-fitted into the connecting shaft.
[0040] Therefore, when the rotating screw rod 25 rotates, it can drive the sliding rod 23 to move up and down on the first connecting plate 21, and the pressing degree of the vibration sensor 29 on the corrugated pipe 4 can be adjusted.
[0041] The bottom of the sliding rod 23 is welded with a connecting bottom 26. The top of the spring 27 is fixed to the bottom of the connecting bottom 26 by circumferential screws. The spring 27 is a compression and rebound type, and the initial compression and rebound force of the spring 27 is 30 Newtons. The bottom of the spring 27 is welded to the upper left side of the contact plate 28. The contact plate 28 is an arc-shaped plate, and the mounting head of the vibration sensor 29 is screwed on the contact plate 28.
[0042] By rotating the screw rod 25 until the contact plate 28 effectively presses on the top of the corrugated pipe 4 and the spring 27 is initially compressed, it indicates that the dynamic change monitoring mechanism is installed before the electrical test.
[0043] In actual work, the corrugated pipe 4 has a slight bend due to the installation error of the GIL side housing 6 and the GIS side housing 1 connected at both ends. Before installation, the lengths of the support frame 20 and the first connecting plate 21 need to be selected according to actual needs. If necessary, the first connecting plate 21 is also adaptively bent to meet the requirement that the emitting heads of the laser rangefinders 22 on both sides are aligned with the circular rings on both sides of the corrugated pipe 4, and the contact plate 28 can effectively press on the upper side of the pipe part of the corrugated pipe 4.
[0044] The working principle of this embodiment is as follows:
[0045] When SF 6 gas is injected into the GIL side housing 6 and the corrugated pipe 4, with the help of the air pressure detector 18, it is convenient for installers or testers to master the air pressure values of the SF 6 gas in the middle GIL side housing 6 and the corrugated pipe 4, which provides good help during the gas filling process and the long-term air pressure data recording process.
[0046] Through the setting of the dynamic change monitoring mechanism, the misalignment situation at both ends of the corrugated pipe 4 and the vibration situation in the corrugated pipe area can be monitored.
[0047] The above is only a preferred embodiment of the present invention, and is not used to limit the protection scope of the present invention.
Claims
1. An electrical test insulation structure for a power transformer, comprising a GIS side housing (1), a GIS side pot-type insulator (2) hermetically connected to one end of the GIS side housing (1), a GIS side conductor (3) respectively connected to both ends of a central contact of the GIS side pot-type insulator (2), and a corrugated tube (4) hermetically connected to one end of the GIS side housing (1), characterized in that: One end of the bellows (4) is sealedly connected to a plurality of sections of GIL side housing (6); the GIS side conductor (3) passes through the bellows (4) to the GIL side housing (6) and is connected to one end of the GIL side conductor (8) via a detachable conductor (7); a GIL side pot-type insulator (5) is sealedly connected between the GIL side housings (6); the GIL side conductor (8) passes through the GIL side housing (6) and is connected to each other via a central electrical terminal of the GIL side pot-type insulator (5); The GIS side shell (1) and the GIL side shell (6) are both supported and fixed on the ground by supporting members. A second fixing frame (19) is provided on the GIL side shell (6) near the bellows (4). A connecting plate (21) is connected to the second fixing frame (19) via a supporting frame (20). A dynamic change monitoring mechanism is provided on the connecting plate (21). The dynamic change monitoring mechanism is used to monitor the vibration and deformation dynamics of the bellows (4) in real time.
2. The electrical test insulation structure of a power transformer according to claim 1, characterized in that: The support member comprises a fixing frame (9) which is respectively fixedly mounted on the GIS side shell (1) and the GIL side shell (6); the bottom of the fixing frame (9) is connected to a supporting column (10); the bottom of the supporting column (10) is connected to a base (11); and both sides of the base (11) are respectively fixed to the ground by expansion bolts.
3. The electrical test insulation structure of a power transformer according to claim 1, characterized in that: A gas relief valve (12) is connected to one side of the top of the GIL side shell (6) through a pipe, and a discharge end of the gas relief valve (12) is connected to a discharge pipe (13) through a through-tube, and the discharge pipe (13) is used to discharge SF6 gas in the middle of the GIL side shell (6) and the bellows (4); The bottom of the GIL side shell (6) is connected to a tee (14) via a second pipe connection, and one side end of the tee (14) is connected to a gas filling nozzle (16) via a one-way valve (15). The gas filling nozzle (16) is used for an external SF6 gas tank to add SF6 gas into the middle of the GIL side shell (6) and the bellows (4).
4. The electrical test insulation structure of a power transformer according to claim 3, characterized in that: The other side end of the tee (14) is connected to a gas pressure detector (18) via a lead pipe (17), and the gas pressure detector (18) is used to monitor the SF6 gas pressure in the GIL side shell (6) and the bellows (4) in the middle in real time.
5. The electrical test insulation structure of a power transformer according to claim 1, characterized in that: The dynamic change monitoring mechanism comprises a laser rangefinder (22) arranged on both sides of the connecting plate (21), and the head of the laser rangefinder (22) is aimed at the top of both sides of the bellows (4) and reflective sheets are arranged; A vibration sensor (29) is provided on the connecting plate (21) and in an area between the laser range finders (22). The vibration sensor (29) is used to monitor the vibration of the pipe portion of the corrugated pipe (4) in real time.
6. An electrical test insulation structure for a power transformer according to any one of claims 1 to 5, characterized in that: A sliding rod (23) is slidably arranged on the connecting plate 1 (21), and one side of the top of the sliding rod (23) is connected to the connecting plate 2 (24), and a screw rod (25) is screwed inside the connecting plate 2 (24), and one end of the screw rod (25) is rotatably arranged on the connecting plate 1 (21); The bottom of the sliding rod (23) is connected to a spring (27) via a connecting bottom (26), the bottom of the spring (27) is connected to a contact plate (28), and a vibration sensor (29) is arranged on the contact plate (28).