CN214703854U - High-potential partial discharge detection device for GIS equipment factory test - Google Patents
High-potential partial discharge detection device for GIS equipment factory test Download PDFInfo
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- CN214703854U CN214703854U CN202120161790.7U CN202120161790U CN214703854U CN 214703854 U CN214703854 U CN 214703854U CN 202120161790 U CN202120161790 U CN 202120161790U CN 214703854 U CN214703854 U CN 214703854U
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Abstract
The utility model relates to an electrical equipment technical field particularly, relates to a high potential partial discharge detection device for GIS equipment factory test. The high-potential partial discharge detection device for the factory test of the GIS equipment comprises a gas insulated switchgear, a discharge detection device and a detection background; the gas insulated combined electrical apparatus comprises a cylinder, a basin-type insulator and a central conductor; the basin-type insulator is connected with the cylinder, and the central conductor is accommodated in the cylinder and connected with the basin-type insulator; the discharge detection device is accommodated in the cylinder body and is connected with the central conductor; the detection background is in communication connection with the discharge detection device. This a high potential partial discharge detection device for GIS equipment factory test can effectively shield external test return circuit to can shield the interference of external test return circuit, and then improve the sensitivity that partial discharge detected, effectively improve partial discharge detection ability, promote GIS equipment factory test's efficiency.
Description
Technical Field
The utility model relates to an electrical equipment technical field particularly, relates to a high potential partial discharge detection device for GIS equipment factory test.
Background
After a gas-insulated switchgear (GIS) is assembled in a factory, a series of factory delivery tests are required to be carried out to ensure the quality of an installation process and timely find metal foreign matters and defects of solid insulation parts which are not cleaned up after installation, wherein the tests comprise a power frequency withstand voltage test, a lightning impulse test and a partial discharge test.
The partial discharge test is an effective test means for finding latent defects in the GIS. According to regulations, the partial discharge level of the GIS equipment with the voltage class of 110kV and above cannot exceed 5pC in the whole factory test, and the partial discharge of the insulation piece cannot exceed 3pC in the single test. The requirement for 1100kVGIS equipment is higher, the factory partial discharge level of the whole GIS equipment cannot exceed 3pC, and the single partial discharge of the insulating part cannot exceed 2 pC.
Therefore, the partial discharge level of the whole test loop must be lower than 2pC in factory test. Due to the pressure resistance of the factory, the test loop conditions are complex, and more interference is often introduced. And during the working period, the external construction and other conditions can generate larger interference, and the test result is interfered by the power supply loop. Therefore, the partial discharge test is usually performed at night, which is inconvenient. Meanwhile, great efforts are often spent to eliminate the interference of an external test loop, and the test efficiency is greatly influenced.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide a high potential partial discharge detection device for GIS equipment factory test, it can effectively shield external interference, and then improves the sensitivity that partial discharge detected, effectively improves the ability that partial discharge detected to promote GIS equipment factory test's efficiency.
The embodiment of the utility model is realized like this:
the utility model provides a high potential partial discharge detection device for GIS equipment delivery test, which comprises a gas insulated switchgear, a discharge detection device and a detection background;
the gas insulated combined electrical apparatus comprises a cylinder, a basin-type insulator and a central conductor; the basin-type insulator is connected with the cylinder, and the central conductor is accommodated in the cylinder and connected with the basin-type insulator;
the discharge detection device is accommodated in the cylinder body and is connected with the central conductor; the detection background is in communication connection with the discharge detection device.
In an optional implementation manner, the high-potential partial discharge detection device for the GIS equipment factory test further includes a communication unit, the communication unit is electrically connected to the discharge detection device, and the communication unit is configured to transmit a detection signal output by the discharge detection device to a detection background.
In an alternative embodiment, the connection of the discharge detection device and the central conductor is provided with an epoxy insulating ring.
In an optional implementation mode, the barrel is provided with a communication hand hole for communicating the inner cavity of the barrel with the outside.
In an optional embodiment, the discharge detection device comprises a metal shield, a detection impedance, an amplification filtering unit, a synchronization unit and a sampling unit; the metal shielding body is provided with a containing cavity, and the detection impedance, the amplification filtering unit, the synchronization unit and the sampling unit are contained in the containing cavity;
the input end of the detection impedance is electrically connected with the central conductor, and the detection impedance is used for inducing pulse current in the gas insulated switchgear;
the amplifying and filtering unit is electrically connected with the output end of the detection impedance and is used for receiving the local discharge pulse current output by the detection impedance and amplifying and de-noising the local discharge pulse current;
the synchronous unit is electrically connected with the input end of the detection impedance and is used for sensing a power frequency current signal and acquiring power frequency phase information;
the sampling unit is electrically connected with the synchronizing unit and the amplifying and filtering unit and is used for receiving the discharging pulse current signal output by the amplifying and filtering unit and the same voltage signal output by the synchronizing unit and outputting a detection signal.
In an optional embodiment, the sampling unit supports a channel threshold trigger mode, a sampling rate of the sampling unit is not lower than 5Ms/S, a bandwidth is not lower than 2MHz, and a memory is not lower than 1 GB.
In an alternative embodiment, the sampling unit has two input channels, wherein one input channel is used for receiving the partial discharge pulse current signal output by the amplifying and filtering unit, and the other input channel is used for receiving the same voltage signal output by the synchronizing unit.
In an optional embodiment, the high-potential partial discharge detection device for the GIS equipment factory test further includes a communication unit accommodated in the metal shield, and the discharge detection device further includes a power supply unit electrically connected to the amplification and filtering unit, the sampling unit, and the communication unit.
In an alternative embodiment, the discharge detection device further includes a metal connection portion connected to the metal shield, and the metal shield is electrically connected to the input end of the detection impedance and to the central conductor.
In an alternative embodiment, an epoxy resin insulating ring is arranged at the joint of the discharge detection device and the central conductor;
the epoxy resin insulating ring is sleeved on the part of the metal connecting part outside the metal shielding body.
The utility model discloses beneficial effect includes:
the high-potential partial discharge detection device for the factory test of the GIS equipment comprises a gas insulated switchgear, a discharge detection device and a detection background; the gas insulated combined electrical apparatus comprises a cylinder, a basin-type insulator and a central conductor; the basin-type insulator is connected with the cylinder, and the central conductor is accommodated in the cylinder and connected with the basin-type insulator; the discharge detection device is accommodated in the cylinder body and is connected with the central conductor; the detection background is in communication connection with the discharge detection device.
Therefore, when the gas insulated switchgear generates partial discharge under the test voltage, the discharge pulse signal is converted into the pulse signal which can be analyzed and processed by the detection background through the discharge detection device, and the partial discharge test of the gas insulated switchgear is completed. In the process, the discharge detection device is accommodated in the cylinder body, so that an external test loop can be effectively shielded, the interference of the external test loop can be shielded, the sensitivity of partial discharge detection is improved, the partial discharge detection capability is effectively improved, and the factory test efficiency of the GIS equipment is improved.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
Fig. 1 is a schematic structural diagram of a high potential partial discharge detection device for a factory test of a GIS device in an embodiment of the present invention;
fig. 2 is a schematic structural diagram of the discharge detection device in the embodiment of the present invention.
200-high potential partial discharge detection device for GIS equipment delivery test; 210-gas insulated switchgear; 220-discharge detection means; 230-detect background; 211-cylinder; 212-basin insulator; 213-a center conductor; 240-a communication unit; 251-an epoxy insulating ring; 252-communication hand hole; 221-a metal shield; 222-detecting impedance; 223-an amplification filtering unit; 224-a synchronization unit; 225-a sampling unit; 226-a power supply unit; 227-metal connection site.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate the position or positional relationship based on the position or positional relationship shown in the drawings, or the position or positional relationship which is usually placed when the product of the present invention is used, and are only for convenience of description and simplification of the description, but do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.
Furthermore, the terms "horizontal", "vertical" and the like do not imply that the components are required to be absolutely horizontal or pendant, but rather may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.
In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Referring to fig. 1 and fig. 2, fig. 1 shows a structure of a high potential partial discharge detection device for a GIS device factory test in an embodiment of the present invention, fig. 2 shows a structure of a discharge detection device in an embodiment of the present invention, this embodiment provides a high potential partial discharge detection device 200 for a GIS device factory test, the high potential partial discharge detection device 200 for a GIS device factory test includes a gas insulated switchgear 210, a discharge detection device 220, and a detection background 230;
the gas insulated switchgear 210 includes a cylinder 211, a basin insulator 212, and a center conductor 213; the basin insulator 212 is connected with the cylinder 211, and the central conductor 213 is accommodated in the cylinder 211 and connected with the basin insulator 212;
the discharge detection device 220 is accommodated in the cylinder 211 and connected with the central conductor 213; the detection background 230 is in communication with the discharge detection device 220.
Referring to fig. 1 and 2, the high-potential partial discharge detection apparatus 200 for the factory test of the GIS device has the following working principle:
the high-potential partial discharge detection device 200 for the GIS equipment factory test comprises a gas insulated switchgear 210, a discharge detection device 220 and a detection background 230; the gas insulated switchgear 210 includes a cylinder 211, a basin insulator 212, and a center conductor 213; the basin insulator 212 is connected with the cylinder 211, and the central conductor 213 is accommodated in the cylinder 211 and connected with the basin insulator 212; the discharge detection device 220 is accommodated in the cylinder 211 and connected to the central conductor 213; the detection background 230 is in communication with the discharge detection device 220.
Therefore, when the gas insulated switchgear 210 is in partial discharge under the test voltage, the discharge detection device 220 converts the discharge pulse signal into a pulse signal that can be analyzed and processed by the detection background 230, thereby completing the partial discharge test on the gas insulated switchgear 210. In this process, discharge detection device 220 holding is in barrel 211, so can effectively shield external test return circuit to can shield the interference of external test return circuit, and then improve the sensitivity that partial discharge detected, effectively improve partial discharge detection ability, promote the efficiency that GIS equipment dispatched from the factory and tested.
Further, referring to fig. 1 and fig. 2, in the present embodiment, when the discharge detection device 220 is disposed, the discharge detection device 220 may include a metal shield 221, a detection impedance 222, an amplification filtering unit 223, a synchronization unit 224, and a sampling unit 225; the metal shield 221 includes a cavity, and the detection impedance 222, the amplification and filtering unit 223, the synchronization unit 224, and the sampling unit 225 are all accommodated in the cavity.
The input terminal of the sensing impedance 222 is electrically connected to the central conductor 213, and the sensing impedance 222 is used for sensing a pulse current in the gas insulated switchgear 210.
The amplifying and filtering unit 223 is electrically connected with the output end of the detection impedance 222, and the amplifying and filtering unit 223 is used for receiving the local discharge pulse current output by the detection impedance 222 and amplifying and denoising the local discharge pulse current; in this embodiment, the frequency band of the amplification filter may be 20kHz to 2MHz, and the gain may be 50 dB.
The synchronization unit 224 is electrically connected with the input end of the detection impedance 222, and the synchronization unit 224 is used for sensing a power frequency current signal and acquiring power frequency phase information; in this embodiment, the synchronization unit 224 may adopt a rogowski coil, and is clamped on a metal connection line between the detection impedance 222 and the metal connection portion 227.
The sampling unit 225 is electrically connected to the synchronizing unit 224 and the amplifying and filtering unit 223, and the sampling unit 225 is configured to receive the discharging pulse current signal output by the amplifying and filtering unit 223 and the same voltage signal output by the synchronizing unit 224, and output a detection signal. It should be noted that, in this embodiment, the sampling unit 225 supports a channel threshold trigger mode, the sampling rate of the sampling unit 225 is not lower than 5Ms/S, the bandwidth is not lower than 2MHz, and the memory is not lower than 1 GB; and the sampling unit 225 has two input channels, wherein one input channel is used for receiving the partial discharge pulse current signal output by the amplification filtering unit 223, and the other input channel is used for receiving the same voltage signal output by the synchronization unit 224.
Based on the above structure, referring to fig. 1 and fig. 2, in this embodiment, in order to enable the detection background 230 to receive the signal output by the discharge detection device 220 so as to analyze and process signal data acquired during the partial discharge test of the gas insulated switchgear 210, the high-potential partial discharge detection device 200 for the factory test of the GIS equipment further includes a communication unit 240, the communication unit 240 is electrically connected to the discharge detection device 220, and the communication unit 240 is configured to transmit the detection signal output by the discharge detection device 220 to the detection background 230.
It should be noted that, in this embodiment, the communication unit 240 may communicate with the detection background 230 in a WIFI wireless synchronization manner, and in order to ensure the communication connection between the detection background 230 and the discharge detection device 220 and facilitate the maintenance of the high-potential partial discharge detection device 200 for the GIS factory test, therefore, the cylinder 211 is provided with a communication hand hole 252 for communicating the inner cavity of the cylinder 211 with the outside for installing the WIIFI microstrip antenna, and the outside is filled with epoxy resin, thereby avoiding corona occurring at high voltage.
Further, referring to fig. 1 and fig. 2, the discharge detection apparatus 220 further includes a power supply unit 226, the power supply unit 226 is electrically connected to the amplification filtering unit 223 and the sampling unit 225, and the power supply unit 226 is configured to provide electric energy to the amplification filtering unit 223 and the sampling unit 225. In order to reduce the external interference of the external shield and the interference of the power supply loop to the partial discharge test, in this embodiment, the high-potential partial discharge detection apparatus 200 for the GIS equipment factory test further includes a communication unit 240 accommodated in the metal shield 221, and the discharge detection apparatus 220 further includes a power supply unit 226, and the power supply unit 226 is electrically connected to the amplification filtering unit 223, the sampling unit 225 and the communication unit 240. That is, in the present embodiment, when the power supply unit 226 and the communication unit 240 are disposed, both the power supply unit 226 and the communication unit 240 can be accommodated in the metal shield 221, so as to shield the interference of the power circuit to the partial discharge test, thereby improving the sensitivity of the partial discharge detection and effectively improving the partial discharge detection capability.
Further, referring to fig. 1 and 2, in order to reduce the interference of the external structure to the structure accommodated in the metal shield 221, in the present embodiment, an epoxy insulating ring 251 is disposed at the connection between the discharge detection device 220 and the central conductor 213. In this embodiment, when the detecting impedance 222 and the central conductor 213 are connected, the discharge detecting apparatus 220 further includes a metal connecting portion 227 connected to the metal shield 221, and the metal shield 221 is electrically connected to the input end of the detecting impedance 222 and the central conductor 213.
Thus, the epoxy insulating ring 251 located at the connection between the discharge detection device 220 and the central conductor 213 can be sleeved on the portion of the metal connection 227 outside the metal shield 221. When the detection impedance 222 is provided, the detection impedance 222 may be a local discharge pulse current sensing impedance made of an iron core, an input end of the primary winding is connected to the metal connection portion 227, the other end of the primary winding is connected to the metal shield 221, and a secondary signal output is connected to the amplification filter unit 223.
The above description is only an example of the present invention, and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. The utility model provides a high potential partial discharge detection device for GIS equipment factory test which characterized in that:
the high-potential partial discharge detection device for the GIS equipment delivery test comprises a gas insulated switchgear, a discharge detection device and a detection background;
the gas insulated combined electrical apparatus comprises a cylinder, a basin-type insulator and a central conductor; the basin-type insulator is connected with the cylinder, and the central conductor is accommodated in the cylinder and connected with the basin-type insulator;
the discharge detection device is accommodated in the cylinder body and is connected with the central conductor; the detection background is in communication connection with the discharge detection device.
2. The high potential partial discharge detection device for the factory test of the GIS equipment according to claim 1, characterized in that:
the high-potential partial discharge detection device for the GIS equipment factory test further comprises a communication unit, the communication unit is electrically connected with the discharge detection device, and the communication unit is used for transmitting a detection signal output by the discharge detection device to the detection background.
3. The high-potential partial discharge detection device for the GIS equipment factory test according to claim 2, characterized in that:
and an epoxy resin insulating ring is arranged at the joint of the discharge detection device and the central conductor.
4. The high-potential partial discharge detection device for the GIS equipment factory test according to claim 2, characterized in that:
the barrel is provided with a communication hand hole for communicating the inner cavity of the barrel with the outside.
5. The high potential partial discharge detection device for the factory test of the GIS equipment according to any one of claims 1 to 4, characterized in that:
the discharge detection device comprises a metal shield, a detection impedance, an amplification filtering unit, a synchronization unit and a sampling unit; the metal shielding body is provided with a cavity, and the detection impedance, the amplification filtering unit, the synchronization unit and the sampling unit are all contained in the cavity;
the input end of the detection impedance is electrically connected with the central conductor, and the detection impedance is used for inducing pulse current in the gas insulated switchgear;
the amplifying and filtering unit is electrically connected with the output end of the detection impedance and is used for receiving the local discharge pulse current output by the detection impedance and amplifying and de-noising the local discharge pulse current;
the synchronous unit is electrically connected with the input end of the detection impedance and is used for sensing a power frequency current signal and acquiring power frequency phase information;
the sampling unit is electrically connected with the synchronizing unit and the amplifying and filtering unit, and is used for receiving the discharging pulse current signal output by the amplifying and filtering unit and the same voltage signal output by the synchronizing unit and outputting a detection signal.
6. The high-potential partial discharge detection device for the GIS equipment factory test according to claim 5, characterized in that:
the sampling unit supports a channel threshold triggering mode, the sampling rate of the sampling unit is not lower than 5Ms/S, the bandwidth is not lower than 2MHz, and the memory is not lower than 1 GB.
7. The high-potential partial discharge detection device for the GIS equipment factory test according to claim 5, characterized in that:
the sampling unit is provided with two input channels, wherein one input channel is used for receiving the local discharge pulse current signal output by the amplifying and filtering unit, and the other input channel is used for receiving the same voltage signal output by the synchronizing unit.
8. The high-potential partial discharge detection device for the GIS equipment factory test according to claim 5, characterized in that:
the high-potential partial discharge detection device for the GIS equipment factory test further comprises a communication unit accommodated in the metal shield, and the discharge detection device further comprises a power supply unit which is electrically connected with the amplification filtering unit, the sampling unit and the communication unit.
9. The high-potential partial discharge detection device for the GIS equipment factory test according to claim 5, characterized in that:
the discharge detection device further comprises a metal connecting part connected with the metal shielding body, and the metal shielding body is electrically connected with the input end of the detection impedance and the central conductor.
10. The high potential partial discharge detection device for the GIS equipment factory test according to claim 9, wherein:
an epoxy resin insulating ring is arranged at the joint of the discharge detection device and the central conductor;
the epoxy resin insulating ring is sleeved on the part of the metal connecting part outside the metal shielding body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202120161790.7U CN214703854U (en) | 2021-01-21 | 2021-01-21 | High-potential partial discharge detection device for GIS equipment factory test |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202120161790.7U CN214703854U (en) | 2021-01-21 | 2021-01-21 | High-potential partial discharge detection device for GIS equipment factory test |
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| CN214703854U true CN214703854U (en) | 2021-11-12 |
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| CN202120161790.7U Active CN214703854U (en) | 2021-01-21 | 2021-01-21 | High-potential partial discharge detection device for GIS equipment factory test |
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