CN209765018U - generator stator rotor grounding test device - Google Patents
generator stator rotor grounding test device Download PDFInfo
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- CN209765018U CN209765018U CN201920419171.6U CN201920419171U CN209765018U CN 209765018 U CN209765018 U CN 209765018U CN 201920419171 U CN201920419171 U CN 201920419171U CN 209765018 U CN209765018 U CN 209765018U
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Abstract
a generator stator and rotor grounding test device comprises a test wire, wherein one end of the test wire is connected with a test clamping device, the other end of the test wire is connected with a first fixed contact, the fixed contact is fixed at the top of an insulation box, a second fixed contact is further arranged at the top of the insulation box, and a certain safety distance exists between the first fixed contact and the second fixed contact; a remote control lifting device is arranged in the insulating box and used for driving the safety support to move up and down, so that the first static contact and the second static contact are connected or disconnected; the second static contact is connected with the input end of the remote control switching resistance device, and the output end of the remote control switching resistance device is used for being electrically connected with the grounding body. The tester can no longer need wear insulating gloves, and handheld insulator spindle is experimental, and only need outside sufficient safe distance, can accomplish whole experiments through remote control operation, can greatly improve whole experimental security.
Description
Technical Field
The utility model belongs to the technical field of the ground test, in particular to generator stator rotor ground test device.
Background
In a stator grounding test in a conventional test project of a generator, test resistors with different resistance values are accessed to the ground from a neutral point of the generator for test and check after the voltage of the generator is increased to a rated voltage.
the existing test method is shown in the attached figure 3 of the specification, after the generator is boosted, a tester wears insulating gloves, stands on an insulating pad, holds an insulating rod with hands, hangs an accessed grounding test resistance test line on the insulating rod head, touches a neutral point of the generator for a short time, withdraws the insulating rod from the neutral point of the generator after observing and recording a test current or measuring a resistance value through relay protection, and generally controls the touch time within 20 seconds. After the test data is recorded, the test resistor with another resistance value is replaced, and the operation is continuously repeated.
normally, the neutral point voltage of the generator is low (alternating current is 50Hz and below 10V), and the neutral point voltage has no influence on testers. However, if a point-to-ground fault of the stator occurs suddenly in the generator during the test, the voltage at the neutral conductor of the generator touched by the insulating rod increases suddenly (when the rated voltage of the generator terminal is 20kV, the neutral voltage of the generator increases to nearly 12kV at most). At this time, the high voltage touching the neutral point of the generator will put the tester holding the insulating rod in a dangerous situation.
the probability of the occurrence of the above situation is small, but once the occurrence of the situation occurs, the personal safety of the testing personnel is seriously harmed. And the fault phenomenon has also appeared in the generator tests of some new power plants. After the new unit is installed and before the new unit is put into operation, various unexpected faults may occur due to various factors such as design defects or installation quality problems.
The same operation method is also needed in the grounding test of the generator rotor.
Therefore, a technical scheme is urgently needed to solve the problem that the personal safety of testing personnel is seriously harmed due to the fact that the unexpected stator grounding fault possibly occurs in the testing process.
SUMMERY OF THE UTILITY MODEL
In view of the technical problem that the background art exists, the utility model provides a generator stator rotor ground test device, the tester can no longer need wear insulating gloves, and handheld insulator spindle is experimental, and only needs outside sufficient safe distance, can accomplish whole experiments through remote control operation, can greatly improve whole experimental security.
In order to solve the technical problem, the utility model discloses following technical scheme has been taken and has been realized:
a generator stator and rotor grounding test device comprises a test wire, wherein one end of the test wire is connected with a test clamping device, the other end of the test wire is connected with a first fixed contact, the fixed contact is fixed at the top of an insulation box, a second fixed contact is further arranged at the top of the insulation box, and a gap is formed between the first fixed contact and the second fixed contact;
A remote control lifting device is arranged in the insulating box and comprises an electric lifting rod; the top of the electric lifting rod is connected with a safety support, a first moving contact and a second moving contact are respectively arranged on two sides of the safety support, and a fuse is connected between the first moving contact and the second moving contact; the remote control lifting device is used for driving the safety support to move up and down, so that the first fixed contact and the second fixed contact are connected or disconnected; the second static contact is connected with the input end of the remote control switching resistance device through a test wire, and the output end of the remote control switching resistance device is used for being electrically connected with the grounding body; the remote control switching resistance device is provided with remote control receiving switches, and each remote control receiving switch is correspondingly connected with a resistor in series.
In a preferred scheme, the remote control switching resistor device comprises a plurality of resistors, the plurality of resistors are at least divided into two groups of resistor modules, resistor units in each group of resistor modules are connected in parallel, and each group of resistor modules are connected in series; the input end and the output end of the remote control switching resistor device are wiring terminals which are arranged on the base; the input end and the output end of the remote control switching resistor device are connected with each group of resistor modules in series; and the remote control receiving switch controls the switching on and off through a second remote controller.
in a preferred scheme, the remote control receiving switch comprises a controller, wherein the input end of the controller is electrically connected with the wireless receiving module, and the output end of the controller is electrically connected with a coil of the relay; the wireless receiving module is in wireless connection with the second remote controller, and the normally open point of the relay is connected with the resistor in series.
in a preferred scheme, the number of the resistors in the remote-control switching resistor device is twelve, wherein six resistor units are a group of resistor modules, the resistors in each group of resistor modules are firstly connected in parallel, and the two groups of resistor modules are then connected in series.
In the preferred scheme, the first fixed contact and the second fixed contact are respectively connected with a test wire through a wiring terminal; the first moving contact and the second moving contact are connected with a fuse through a wiring terminal; silver-plated contacts are adopted between the first fixed contact and the first moving contact and between the second fixed contact and the second moving contact.
In a preferred scheme, an electric lifting rod of the remote control lifting device is electrically connected with a remote control controller, the remote control controller is provided with a working power supply by a battery pack, and the remote control controller is wirelessly connected with a first remote controller; the electric lifting rod, the remote controller and the battery pack are all fixed on the bottom plate of the insulation box.
in the preferred scheme, a partition board is arranged in the middle of the insulation box, the insulation box is divided into an upper space and a lower space by the partition board, and a hole for the movement of the electric lifting rod is formed in the middle of the partition board; the part of the insulation box above the partition plate is made of transparent materials.
in a preferred scheme, the output end of the remote control switching resistance device is connected with the grounding body through a grounding wire.
In a preferred embodiment, the test clamping device is a test clamp.
This patent can reach following beneficial effect:
1. Before the generator is started and tested, a tester only needs to connect a test wire, a test clamping device, an insulation box and a remote control switching resistance device with a tested generator and the ground, and then when the generator is started and tested, all tests can be completed only by remote control operation of a first remote controller and a second remote controller outside a sufficient safety distance; the tester does not need to wear insulating gloves any more, and holds the insulating rod by hand to repeatedly perform the connection test, so that the safety of the whole test and the test rapidity are greatly improved; the device realizes the complete isolation of the tester and the high-voltage live equipment, and in the whole test process, the tester remotely operates outside the safe distance to complete the test, so that even if an accidental short circuit occurs inside the generator, the high-voltage live equipment can be reliably disconnected, a fault loop can be reliably cut off, and complete personal safety guarantee is provided for the tester;
2. The automatic operation of the grounding test of the stator and the rotor of the generator is realized; the complicated operation mode that in the conventional test method, a tester needs to repeatedly hold the insulating rod to touch the electrified equipment, frequently adjust the test resistance and easily touch other electrified equipment by mistake is avoided, the new method is simpler and more convenient and is easy to operate, and the test time is effectively shortened;
3. The resistors in the remote control switching resistor device are connected in series and parallel, so that different resistance values can be switched according to test requirements, and the requirements of different grounding resistance values of different power plants are met;
4. The electric lifting rod of the remote control lifting device can adjust the stroke length and meet the requirements of measurement of different voltage grades;
5. the upper part of the insulating box is made of transparent materials, so that the action condition of the mechanism can be easily observed, and if abnormal conditions occur, the test can be immediately stopped;
6. The fuse support is provided with a fuse, and when the voltage rises, the fuse can be instantly fused to play a role in protection;
7. A double-break arc extinguishing design is adopted between the first fixed contact and the first moving contact as well as between the second fixed contact and the second moving contact, so that the capacity of breaking an arc is increased;
8. Silver-plated contacts are adopted between the first fixed contact and the first moving contact and between the second fixed contact and the second moving contact, so that the contact resistance can be reduced, and the contact quality is improved;
9. the first remote controller and the second remote controller are designed separately, and the first remote controller and the second remote controller are not designed together because the remote control lifting device can be independently used as a high-power remote control switch which can be matched with other devices to be switched on or off, such as a capacitor, an inductor and the like, or other devices needing to cut off large current;
10. The device has low hardware cost, simple structure and easy assembly.
drawings
The invention will be further explained with reference to the following figures and examples:
FIG. 1 is a schematic view of the overall connection of the present invention;
Fig. 2 is an enlarged view of a portion a of fig. 1, which is an internal wiring diagram of a remote-control switching resistor device according to the present invention, wherein RM represents a remote-control receiving switch, and numerals following RM represent numbers of the remote-control receiving switch;
FIG. 3 is a schematic diagram illustrating the effect of the prior art device in use;
Fig. 4 is a control diagram of the remote-control switching resistor device of the present invention.
In the figure: the device comprises a test wire 1, a test clamping device 2, a first fixed contact 301, a second fixed contact 302, an insulating box 4, a partition plate 401, a remote control lifting device 5, a first remote controller 501, a remote control controller 502, a battery pack 503, an electric lifting rod 504, a safety bracket 6, a first movable contact 701, a second movable contact 702, a remote control switching resistance device 8, a base 801, a second remote controller 802, a fuse 9, a ground wire 10, an insulating pad 11 and an insulating rod 12.
Detailed Description
a preferred scheme is as shown in fig. 1 and fig. 2, the generator stator and rotor ground test device comprises a test wire 1, one end of the test wire 1 is connected with a test clamping device 2, the other end of the test wire 1 is connected with a first fixed contact 301, the fixed contact 3 is fixed on the top of an insulation box 4, a second fixed contact 302 is further arranged on the top of the insulation box 4, and a certain safety distance is reserved between the first fixed contact 301 and the second fixed contact 302; the distances between the first fixed contact 301 and the second fixed contact 302 corresponding to different voltage levels are different, and when the voltage is 12kV, the distance between the first fixed contact 301 and the second fixed contact 302 can be 120 mm;
A remote control lifting device 5 is arranged in the insulating box 4, and the remote control lifting device 5 comprises an electric lifting rod 504; the top of the electric lifting rod 504 is connected with a safety support 6, two sides of the safety support 6 are respectively provided with a first moving contact 701 and a second moving contact 702, a fuse 9 is connected between the first moving contact 701 and the second moving contact 702, the first moving contact 701 is matched with the first fixed contact 301, and the second moving contact 702 is matched with the second fixed contact 302; the remote control lifting device 5 is used for driving the safety support 6 to move up and down, so that the first fixed contact 301 and the second fixed contact 302 are connected or disconnected; the second fixed contact 302 is connected with the input end of the remote control switching resistance device 8 through the test line 1, and the output end of the remote control switching resistance device 8 is used for being electrically connected with the grounding body; the remote control switching resistance device 8 is provided with remote control receiving switches, and each remote control receiving switch is correspondingly connected with a resistor in series.
Furthermore, the input end and the output end of the remote control switching resistance device 8 are wiring terminals, the remote control switching resistance device 8 comprises a plurality of resistors, the plurality of resistors are at least divided into two groups of resistance modules, the resistance units in each group of resistance modules are connected in parallel, and each group of resistance modules are connected in series; the input end and the output end of the remote control switching resistor device 8 are wiring terminals, and the wiring terminals are arranged on the base 801; the input end and the output end of the remote control switching resistance device 8 are connected with each group of resistance modules in series; the remote control receiving switch controls the switching on and off through the second remote controller 802.
Furthermore, the remote control receiving switch comprises a controller, the input end of the controller is electrically connected with the wireless receiving module, and the output end of the controller is electrically connected with a coil of the relay; the wireless receiving module is wirelessly connected with the second remote controller 802, and the normally open point of the relay is connected with the resistor in series;
The controller adopts an ARM control chip, the model of the ARM control chip is STM32F103C6T6, the model of the relay is preferably JQC-3FF-1H-12V, the wireless receiving module is preferably XC4366, and a control wiring diagram of the ARM control chip is shown in the attached figure 4.
Furthermore, the number of the resistors in the remote-control switching resistor device 8 is twelve, wherein six resistor units are a group of resistor modules, the resistors in each group of resistor modules are connected in parallel, and the two groups of resistor modules are connected in series; the resistance value of each resistor is between 470 Ω and 20K Ω, preferably 5K Ω.
Further, the first fixed contact 301 and the second fixed contact 302 are respectively connected with the test line 1 through a connection terminal; the first moving contact 701 and the second moving contact 702 are connected with a fuse 9 through a connecting terminal; silver-plated contacts are adopted between the first fixed contact 301 and the first moving contact 701 and between the second fixed contact 302 and the second moving contact 702;
the first moving contact 701 and the second moving contact 702 adopt a spring plate structure or a spring structure, so that reliable connection with the first fixed contact 301 and the second fixed contact 302 can be ensured.
Further, an electric lifting rod 504 of the remote control lifting device 5 is electrically connected with a remote control controller 502, the battery pack 503 supplies working power to the remote control controller 502, and the remote control controller 502 is wirelessly connected with a first remote controller 501; the electric lifting rod 504, the remote controller 502 and the battery pack 503 are all fixed on the bottom plate of the insulating box 4;
The remote control lifting device 5 can adopt a direct current electric lifting rod produced by a Longxiang enterprise, the model number of the direct current electric lifting rod is XTL100, the working voltage is DC12V, and the product has a remote control function; the battery 503 adopts a 12V lithium battery with the capacity of 16800 mAh.
furthermore, a partition board 401 is arranged in the middle of the insulation box 4, the insulation box 4 is divided into an upper space and a lower space by the partition board 401, and a hole for the movement of the electric lifting rod 504 is cut in the middle of the partition board 401; the part of the insulating box 4 above the partition board 401 is made of transparent materials;
The part of the insulation box 4 below the partition board 401 is made of bakelite, so that the insulation box has good insulation property; the portion of the insulating case 4 above the partition 401 is made of transparent plastic.
further, the output end of the remote-control switching resistance device 8 is connected to the grounding body through a grounding wire 10.
further, the test holding device 2 is a test clamp.
A test method of a generator stator and rotor grounding test device is described with reference to the accompanying drawings 1 and 3, and the operation steps are as follows:
Step one, a first remote controller 501 is used for adjusting the electric lifting rod 504 to move so that the first fixed contact 301 and the second fixed contact 302 are disconnected with the first moving contact 701 and the second moving contact 702; the remote receiving switches in the remote switching resistor device 8 are all in an off state; one end of a test wire 1 is connected to a tested point through a test clamping device 2, the other end of the test wire 1 is connected with a first fixed contact 301, a second fixed contact 302 is connected with the input end of a remotely-controllable switching resistance device 8 through the test wire 1, and the output end of the remotely-controllable switching resistance device 8 is electrically connected with a grounding body;
Step two, determining a grounding resistance value to be accessed; the second remote controller 802 selectively closes the corresponding remote receiving switch, and puts in the resistance value measured for the first time, such as 10K Ω;
Step three, the first remote controller 501 is used for adjusting the electric lifting rod 504 to move, so that the first fixed contact 301 is contacted with the first moving contact 701, and the second fixed contact 302 is contacted with the second moving contact 702; namely, the first fixed contact 301 and the second fixed contact 302 are ensured to be in a connection state;
Step four, starting to record the grounding resistance value measured from the generator relay protection device;
Step five, after a certain time, 20 seconds are recommended here, and the connection between the first fixed contact 301 and the first moving contact 701 and the connection between the second fixed contact 302 and the second moving contact 702 are disconnected;
step six, switching a remote control receiving switch, putting a resistance value measured for the second time, such as 5K omega, and repeating the steps three to five;
And step seven, after repeating the measurement in the step six for N times, wherein N represents the test times, 8 times are recommended to be taken out of N, after the test is finished, the test clamping device 2, the remote control lifting device 5 and the remote control switching resistance device 8 are withdrawn in sequence, and finally the grounding wire 10 is detached.
In the above steps, if the voltage of the neutral point of the generator abnormally rises to 12kV due to an internal fault of the generator in the test process, the fuse in the fuse box is fused, the test loop is cut off, and meanwhile, the connection between the first fixed contact 301 and the second fixed contact 302 can be disconnected through the remote control lifting device 5, so that the reliable disconnection of the test loop is ensured.
In the whole test process, the testers are remotely operated beyond the electrical safety distance, so that the testers are not electrically harmed; the testers do not need to wear insulating gloves, hold the insulating rods in hand and touch the live equipment, and all test items can be completed only by holding the first remote controller 501 and the second remote controller 802 outside the safe distance and performing remote control operation; the schematic view is shown in FIG. 1.
The above-mentioned embodiments are merely preferred embodiments of the present invention, and should not be considered as limitations of the present invention, and the protection scope of the present invention should be defined by the technical solutions described in the claims, and includes equivalent alternatives of technical features in the technical solutions described in the claims. Namely, equivalent alterations and modifications within the scope of the invention are also within the scope of the invention.
Claims (9)
1. The utility model provides a generator stator rotor ground test device, includes test wire (1), its characterized in that: one end of a test wire (1) is connected with the test clamping device (2), the other end of the test wire (1) is connected with a first fixed contact (301), the first fixed contact (301) is fixed to the top of the insulating box (4), a second fixed contact (302) is further arranged on the top of the insulating box (4), and a safety distance exists between the first fixed contact (301) and the second fixed contact (302);
A remote control lifting device (5) is arranged in the insulation box (4), and the remote control lifting device (5) comprises an electric lifting rod (504); the top of the electric lifting rod (504) is connected with a safety support (6), a first moving contact (701) and a second moving contact (702) are respectively arranged on two sides of the safety support (6), and a fuse (9) is connected between the first moving contact (701) and the second moving contact (702); the remote control lifting device (5) is used for driving the safety support (6) to move up and down, so that the first fixed contact (301) and the second fixed contact (302) are connected or disconnected; the second fixed contact (302) is connected with the input end of the remote control switching resistance device (8) through the test wire (1), and the output end of the remote control switching resistance device (8) is used for being electrically connected with the grounding body; the remote control switching resistance device (8) is provided with remote control receiving switches, and each remote control receiving switch is correspondingly connected with a resistor in series.
2. the generator stator rotor grounding test device according to claim 1, wherein: the remote control switching resistor device (8) comprises a plurality of resistors, the resistors are at least divided into two groups of resistor modules, the resistor units in each group of resistor modules are connected in parallel, and each group of resistor modules are connected in series; the input end and the output end of the remote control switching resistor device (8) are wiring terminals, and the wiring terminals are arranged on the base (801); the input end and the output end of the remote control switching resistor device (8) are connected with each group of resistor modules in series; the remote control receiving switch controls the switching on and off through a second remote controller (802).
3. The generator stator rotor grounding test device according to claim 2, wherein: the remote control receiving switch comprises a controller, the input end of the controller is electrically connected with the wireless receiving module, and the output end of the controller is electrically connected with a coil of the relay; the wireless receiving module is wirelessly connected with the second remote controller (802), and the normally open point of the relay is connected with the resistor in series.
4. The generator stator rotor grounding test device according to claim 1, wherein: the number of the resistors in the remote control switching resistor device (8) is twelve, wherein six resistor units are a group of resistor modules, the resistors in each group of resistor modules are connected in parallel, and the two groups of resistor modules are connected in series.
5. The generator stator rotor grounding test device according to claim 1, wherein: the first fixed contact (301) and the second fixed contact (302) are respectively connected with the test wire (1) through wiring terminals; the first moving contact (701) and the second moving contact (702) are connected with a fuse (9) through a wiring terminal; silver-plated contacts are adopted between the first fixed contact (301) and the first moving contact (701) and between the second fixed contact (302) and the second moving contact (702).
6. The generator stator rotor grounding test device according to claim 1, wherein: an electric lifting rod (504) of the remote control lifting device (5) is electrically connected with a remote control controller (502), the remote control controller (502) is provided with a working power supply by a battery pack (503), and the remote control controller (502) is wirelessly connected with a first remote controller (501); the electric lifting rod (504), the remote controller (502) and the battery pack (503) are all fixed on the bottom plate of the insulating box (4).
7. the generator stator rotor grounding test device according to claim 1 or 6, characterized in that: a partition plate (401) is arranged in the middle of the insulation box (4), the insulation box (4) is divided into an upper space and a lower space by the partition plate (401), and a hole for the movement of the electric lifting rod (504) is formed in the middle of the partition plate (401); the part of the insulating box (4) above the partition plate (401) is made of transparent materials.
8. The generator stator rotor grounding test device according to claim 1, wherein: the output end of the remote control switching resistance device (8) is connected with the grounding body through a grounding wire (10).
9. the generator stator rotor grounding test device according to claim 1, wherein: the test clamping device (2) is a test clamp.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920419171.6U CN209765018U (en) | 2019-03-29 | 2019-03-29 | generator stator rotor grounding test device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920419171.6U CN209765018U (en) | 2019-03-29 | 2019-03-29 | generator stator rotor grounding test device |
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| Publication Number | Publication Date |
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| CN209765018U true CN209765018U (en) | 2019-12-10 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201920419171.6U Active CN209765018U (en) | 2019-03-29 | 2019-03-29 | generator stator rotor grounding test device |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109884524A (en) * | 2019-03-29 | 2019-06-14 | 中国长江电力股份有限公司 | A kind of generator stator rotor grounding test apparatus and test method |
-
2019
- 2019-03-29 CN CN201920419171.6U patent/CN209765018U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109884524A (en) * | 2019-03-29 | 2019-06-14 | 中国长江电力股份有限公司 | A kind of generator stator rotor grounding test apparatus and test method |
| CN109884524B (en) * | 2019-03-29 | 2023-11-28 | 中国长江电力股份有限公司 | Generator stator and rotor grounding test device and test method |
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