CN216560779U - Frequency domain dielectric response live-line test system of high-voltage bushing - Google Patents
Frequency domain dielectric response live-line test system of high-voltage bushing Download PDFInfo
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- CN216560779U CN216560779U CN202121931227.XU CN202121931227U CN216560779U CN 216560779 U CN216560779 U CN 216560779U CN 202121931227 U CN202121931227 U CN 202121931227U CN 216560779 U CN216560779 U CN 216560779U
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Abstract
The utility model discloses a frequency domain dielectric response live-line test system of a high-voltage bushing, wherein in the system, a high-frequency voltage injection unit is arranged on a tail screen of the high-voltage bushing, a guide rod is arranged in a shell, one end of the guide rod is connected with a tail screen wiring terminal of the high-voltage bushing through a tail screen connecting interface, one end of a high-pass filter circuit is connected with the other end of the guide rod, the other end of the high-pass filter circuit is connected with a signal input interface, an annular base is sleeved on the low-voltage side of an outer sheath of the high-voltage bushing, one end of at least one insulating column is connected with the annular base and extends towards the direction far away from the high-voltage bushing, an annular current induction plate is sleeved on the low-voltage side of the outer sheath of the high-voltage bushing and is positioned above the annular base, and the annular current induction plate is connected with the other end of the insulating column; the test unit is connected with the voltage output end and the current output end.
Description
Technical Field
The utility model relates to the technical field of high-voltage bushing detection, in particular to a frequency domain dielectric response live-line test system of a high-voltage bushing.
Background
Frequency-domain Dielectric Spectroscopy (FDS) refers to the application of an electric field to a Dielectric medium to describe the Dielectric constant and Dielectric loss tangent versus Frequency over a wide range of frequencies, i.e., the real part of the complex Dielectric constant, the epsilon' (omega) spectrum, and the imaginary part of the complex Dielectric constant, the epsilon "(omega) spectrum. The frequency domain dielectric spectrum refers to that alternating voltages with different frequencies are applied to a sample to obtain the amplitude and the phase of a current flowing through the sample, and dielectric parameters related to the frequency, such as a real part and an imaginary part of a relative complex dielectric constant of the sample, a dielectric loss tangent tan delta and the like, are obtained through calculation. The dielectric losses are different due to the dielectric properties of the dielectric itself, having different polarization and relaxation processes at different frequencies. And drawing a frequency domain dielectric spectrum (FDS) curve of the tested sample according to the parameter values such as the dielectric loss tangent value, the complex capacitance and the like under different frequencies, wherein the curves of different frequency bands can represent different defect types of the casing. At present, the high-voltage side lead of a sleeve needs to be removed for carrying out the frequency domain dielectric spectrum test of the sleeve, the voltage output end (high-voltage end) of a frequency domain dielectric spectrum tester is connected to a guide rod of the sleeve, and the current measuring end is connected to the end screen of the sleeve. Therefore, the device can be developed only when the equipment (such as a transformer, an oil-immersed reactor and the like) is powered off, and the state of the sleeve pipe in operation cannot be tested.
The above information disclosed in this background section is only for enhancement of understanding of the background of the utility model and therefore it may contain information that does not form the prior art that is well known to those of ordinary skill in the art.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a frequency domain dielectric response live test system of a high-voltage bushing, which overcomes the problem that the current test needs equipment power failure and greatly improves the flexibility of the frequency domain dielectric response test work of the high-voltage bushing.
In order to achieve the above purpose, the utility model provides the following technical scheme:
a frequency domain dielectric response live test system for a high voltage bushing of the present invention comprises,
a high-frequency voltage injection unit, which is mounted on the high-voltage bushing end screen, and comprises,
the outer shell is provided with a plurality of grooves,
a tail screen connecting interface arranged at one end of the shell,
a signal input interface disposed at the other end of the housing opposite the end screen connection interface,
a guide rod arranged in the shell, wherein one end of the guide rod is connected with a tail screen binding post of the high-voltage bushing through the tail screen connecting interface,
the high-pass filter circuit comprises a capacitor and a resistor which are connected in series, wherein one end of the capacitor is connected with the signal input interface and serves as an input end, one end of the resistor serves as a grounding end, and the other end of the resistor is connected with the capacitor and serves as an output end and is connected with the guide rod;
a high-frequency current sensing unit, which includes,
an annular base which is sleeved on the low-voltage side of the outer sheath of the high-voltage bushing,
at least one insulating column, one end of which is connected with the annular base and extends towards the direction far away from the high-voltage bushing,
the annular current induction plate is sleeved on the low-voltage side of the outer sheath of the high-voltage bushing and positioned above the annular base, and the annular current induction plate is connected with the other end of the insulating column;
a signal output interface connected with the annular current induction plate,
a frequency domain dielectric spectrum tester, comprising,
a voltage output terminal for inputting a high-frequency voltage signal to the high-voltage bushing via the signal input interface,
a current measuring terminal for obtaining the high-frequency current signal via the signal output interface,
and the test unit is connected with the voltage output end and the current output end.
In the frequency domain dielectric response live test system of the high-voltage bushing, the annular current induction plate is electrically connected with the current measuring end through a coaxial cable core wire, the coaxial cable shielding layer is coated on the coaxial cable core wire, and the coaxial cable core wire is connected with the annular base.
In the frequency domain dielectric response live test system of the high-voltage bushing, the shell is of a cylindrical structure.
In the frequency domain dielectric response live test system of the high-voltage bushing, one end of the shell is provided with an opening, and the end screen connecting interface is packaged in the opening.
In the frequency domain dielectric response live test system of the high voltage bushing, the central axis of the end screen connecting interface is collinear with the central axis of the opening.
In the frequency domain dielectric response live test system of the high-voltage bushing, the end screen connecting interface is sleeved with the sealing ring.
In the frequency domain dielectric response live test system of the high-voltage bushing, the coaxial cable outer shield is grounded.
In the frequency domain dielectric response live test system of the high voltage bushing, the end screen connecting interface is parallel or collinear to the shell.
In the frequency domain dielectric response live test system of the high-voltage bushing, a plurality of insulating columns are connected between the annular current induction plate and the annular base to form a truncated cone structure.
In the frequency domain dielectric response live test system of the high voltage bushing, the diameter of the annular current induction plate is larger than that of the annular base.
In the above technical solution, the frequency domain dielectric response live test system of the high voltage bushing provided by the utility model has the following beneficial effects: the frequency domain dielectric response live test system of the high-voltage bushing can quickly and accurately obtain the frequency domain dielectric spectrum under the condition of no power failure, accurately and efficiently judge different defect types of the high-voltage bushing, does not need to dismantle a high-voltage side lead of the bushing, and is convenient to operate, so that the power failure times and power failure time of equipment are reduced, the test time is shortened, and the test workload is reduced. The utility model obviously improves the safety of the test system.
Drawings
In order to more clearly illustrate the embodiments of the present application or technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present invention, and other drawings can be obtained by those skilled in the art according to the drawings.
FIG. 1 is a schematic diagram of a frequency domain dielectric response live test system for a high voltage bushing in accordance with one embodiment of the present invention;
FIG. 2 is a schematic structural diagram of a high-frequency voltage injection unit of a frequency-domain dielectric response live test system for a high-voltage bushing according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of a high-frequency current sensing unit of a frequency-domain dielectric response live testing system of a high-voltage bushing according to an embodiment of the utility model.
Detailed Description
To make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to fig. 1 to 3 of the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the utility model, as claimed, but is merely representative of selected embodiments of the utility model. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the 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 is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the equipment or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.
Furthermore, the terms "first", "second" and "first" 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. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. 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; 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, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.
In order to make the technical solutions of the present invention better understood, those skilled in the art will now describe the present invention in further detail with reference to the accompanying drawings.
In one embodiment, as shown in fig. 1-3, a frequency domain dielectric response live test system for a high voltage bushing comprises,
a high-frequency voltage injection unit 1, which is mounted to a high-voltage bushing tap, comprising,
the outer shell (4) is provided with a plurality of grooves,
a rear screen connection interface 10, which is arranged at one end of the housing 4,
a signal input interface 9 provided at the other end of the housing 4 with respect to the end screen connection interface 10,
a guide rod 5 arranged in the shell 4, wherein one end of the guide rod 5 is connected with a tail screen binding post of the high-voltage bushing through the tail screen connecting interface 10,
a high-pass filter circuit 6, one end of which is connected to the other end of the guide rod 5, and the other end of which is connected to the signal input interface 9, wherein the high-pass filter circuit 6 comprises a capacitor 7 and a resistor 8 which are connected in series, one end of the capacitor 7 is connected to the signal input interface 9 and serves as an input end, one end of the resistor 8 serves as a ground end, and the other end thereof is connected to the capacitor 7 and serves as an output end which is connected to the guide rod 5;
a high-frequency current sensing unit 2, which includes,
an annular base 12, which is sleeved on the low-voltage side of the outer sheath of the high-voltage bushing, wherein the annular base 12 is provided with a grounding wire,
at least one insulating column 13 having one end connected to said annular base 12 and extending away from said high voltage bushing,
the annular current induction plate 14 is sleeved on the low-voltage side of the outer sheath of the high-voltage bushing to wirelessly receive a high-frequency current signal sent by the high-voltage end of the high-voltage bushing, the annular current induction plate 14 is positioned above the annular base, and the annular current induction plate 14 is connected with the other end of the insulating column 13;
a signal output interface 15 connected with the annular current induction plate 14,
the frequency domain dielectric spectrum tester 3, which includes,
a voltage output terminal for inputting a high-frequency voltage signal to the high-voltage bushing via the signal input interface 9,
a current measuring terminal for obtaining the high-frequency current signal via the signal output interface 15,
and the test unit is connected with the voltage output end and the current output end.
The test unit generates the high frequency voltage signal and receives a high frequency current signal and forms a frequency domain dielectric spectrum.
The frequency domain dielectric response live test system of the high-voltage bushing can carry out bushing frequency domain dielectric response test in the bushing live operation process, the bushing is not required to be powered off in the test process, and a bushing lead is not required to be detached, so that the power-off times and the power-off time of equipment are reduced, the test time is shortened, and the test workload is reduced.
In the preferred embodiment of the frequency domain dielectric response live test system for the high voltage bushing, the annular current sensing plate 14 is electrically connected to the current measuring end through a coaxial cable core, the coaxial cable core is covered by a coaxial cable shielding layer, and the coaxial cable core is connected to the annular base 12.
In the preferred embodiment of the frequency domain dielectric response live test system for the high voltage bushing, the housing 4 is a cylindrical structure.
In the preferred embodiment of the frequency domain dielectric response live test system for the high voltage bushing, an opening is formed at one end of the housing 4, and the end screen connection interface 10 is packaged in the opening.
In the preferred embodiment of the frequency domain dielectric response live test system for high voltage bushings, the central axis of the tap connection interface 10 is collinear with the central axis of the opening.
In the preferred embodiment of the frequency domain dielectric response live test system for the high voltage bushing, the end screen connecting interface 10 is sleeved with the sealing ring 11.
In a preferred embodiment of the system for testing the frequency domain dielectric response of a high voltage bushing with electricity, the coaxial cable outer shield is grounded.
In the preferred embodiment of the frequency domain dielectric response live test system for high voltage bushings, the tap connection interface 10 is parallel or collinear to the housing 4.
In the preferred embodiment of the frequency domain dielectric response live test system for high voltage bushings, a plurality of insulating columns 13 are connected between the annular current sensing plate 14 and the annular base 12 to form a truncated cone structure.
In one embodiment, the system includes a high frequency voltage injection unit 1, a high frequency current sensing unit 2, and a frequency domain dielectric spectrum tester 3. Wherein the high-frequency voltage injection unit 1 is arranged on the end screen of the sleeve, and the high-frequency current induction unit 2 is arranged on the low-voltage side of the outer sheath of the sleeve close to the metal flange. When a casing frequency domain dielectric response test is carried out, the voltage output end of a frequency domain dielectric spectrum tester 3 is connected with a high-frequency voltage injection unit 1 to input voltage signals with different frequencies to the casing; the current measuring end of the tester 3 is connected with the high-frequency current induction unit 2 to obtain a high-frequency current signal.
In one embodiment, the plurality of insulating columns 13 are uniformly distributed on the annular base 12.
In one embodiment, the radius of the annular current sensing plate 14 is greater than the radius of the annular base 12.
In one embodiment, the annular current sensing plate 14 is located above the annular base 12.
In one embodiment, the annular current sensing plate 14 and the coaxial sleeve are disposed within a high voltage bushing.
In one embodiment, the high-frequency voltage injection unit 1 comprises a housing 4, a tap connection interface 10, a guide rod 5, a high-pass filter circuit 6 and a signal input lead.
In one embodiment, the end screen connection interface 10 is made of the same material and has the same thread size as the bushing end screen grounding cover, and is used for connecting the high-frequency voltage injection unit 1 with the bushing. One end of the guide rod 5 is connected with the sleeve end screen binding post, and the other end of the guide rod is connected with the output end of the high-pass filter circuit 6. The output end of the high-pass filter circuit 6 is connected with the guide rod 5, the input end of the high-pass filter circuit is connected with the signal input lead, and the grounding end of the high-pass filter circuit is connected with the shell 4 of the high-frequency voltage injection unit 1, so that the end screen is reliably grounded during the operation of the sleeve.
In one embodiment, the high-pass filter circuit 6 is composed of a capacitor 7 and a resistor 8 which are connected in series. One end of the resistor 8 is a grounding end, the other end of the resistor is connected with the capacitor 7 and is connected with the guide rod 5 as an output end, one end of the capacitor 7 is connected with the resistor 8, and the other end of the capacitor is used as an input end. In the running process of the sleeve, the end screen of the sleeve is grounded through the guide rod 5 and the resistor 8, so that the safe running of the sleeve is ensured. When the frequency domain dielectric response of the live test casing is carried out, the frequency domain dielectric spectrum tester 3 is connected with the input end of the high-pass filter circuit 6 and the capacitor 7 through the signal input lead wire, and high-frequency voltage signals are injected into the end screen of the casing.
In one embodiment, the high frequency current sensing unit 2 includes a ring-shaped current sensing plate 14, a ring-shaped base 12 and signal output leads. The high-frequency current induction unit 2 is arranged at the low-voltage side of the outer sheath of the sleeve close to the metal flange.
In one embodiment, the annular current sensing plate 14 is used to sense high-frequency current signals at the high-voltage end of the bushing. The annular current induction plate 14 is connected with the current measuring end of the frequency domain dielectric spectrum tester 3 and the coaxial cable shielding layer through the coaxial cable core wire and the annular base 12. The annular current induction plate 14 is connected with the annular base 12 through the insulating column 13. The annular base 12 is provided with a grounding lead which is grounded and connected with the frequency domain dielectric spectrum tester 3 during testing, so that the field interference is reduced.
In one embodiment, the system includes a high frequency voltage injection unit 1, a high frequency current sensing unit 2, and a frequency domain dielectric spectrum tester 3. The high-frequency voltage injection unit 1 is used for injecting high-frequency voltage signals into the bushing during operation, and the high-frequency current induction unit 2 is used for wirelessly receiving high-frequency current signals sent by the high-voltage end of the bushing. The frequency domain dielectric spectrum tester 3 is used for generating high-frequency voltage, receiving high-frequency current signals and forming a frequency domain dielectric spectrum. C1 represents the equivalent capacitance between the bushing end shield and the bushing center high voltage conductor bar. C2 represents the geometrical capacitance between the high-voltage conducting rod and the annular current sensing plate in the high-frequency current sensing unit 2. The high-frequency voltage signal generated by the test time-frequency domain dielectric spectrum tester 3 is applied to the sleeve end screen through the high-frequency voltage injection unit 1. The high-frequency voltage generates an induced current on a loop consisting of the equivalent capacitance C1, the geometric C2 in series, which flows into the frequency domain dielectric spectrum tester 3 through the high-frequency current sensing unit 2.
The test process of the frequency domain dielectric response live test system of the high-voltage bushing is as follows:
the frequency domain dielectric spectrum tester 3 generates the high frequency voltage signal and introduces it to the high frequency voltage injection unit 1 via the signal input interface 9,
the high-frequency voltage signal is processed by a high-pass filter circuit 6 and then is connected with the end screen wiring terminal of the high-voltage bushing by a guide rod 5,
the annular current induction plate 14 wirelessly receives a high-frequency current signal sent by the high-voltage end of the high-voltage bushing, and the high-frequency current signal is input into the frequency domain dielectric spectrum tester 3 through the signal output interface 15 to form a frequency domain dielectric spectrum.
Finally, it should be noted that: the embodiments described are only a part of the embodiments of the present application, and not all embodiments, and all other embodiments obtained by those skilled in the art without making creative efforts based on the embodiments in the present application belong to the protection scope of the present application.
While certain exemplary embodiments of the present invention have been described above by way of illustration only, it will be apparent to those of ordinary skill in the art that the described embodiments may be modified in various different ways without departing from the spirit and scope of the utility model. Accordingly, the drawings and description are illustrative in nature and should not be construed as limiting the scope of the utility model.
Claims (10)
1. A frequency domain dielectric response live test system for a high voltage bushing, comprising,
a high-frequency voltage injection unit installed at the high-voltage bushing tap, the high-frequency voltage injection unit including,
the outer shell is provided with a plurality of grooves,
a tail screen connecting interface arranged at one end of the shell,
a signal input interface disposed at the other end of the housing opposite the end screen connection interface,
a guide rod arranged in the shell, wherein one end of the guide rod is connected with a tail screen binding post of the high-voltage bushing through the tail screen connecting interface,
the high-pass filter circuit comprises a capacitor and a resistor which are connected in series, wherein one end of the capacitor is connected with the signal input interface and serves as an input end, one end of the resistor serves as a grounding end, and the other end of the resistor is connected with the capacitor and serves as an output end and is connected with the guide rod;
a high-frequency current sensing unit including,
an annular base which is sleeved on the low-voltage side of the outer sheath of the high-voltage bushing,
at least one insulating column, one end of which is connected with the annular base and extends towards the direction far away from the high-voltage bushing,
the annular current induction plate is sleeved on the low-voltage side of the outer sheath of the high-voltage bushing and positioned above the annular base, and the annular current induction plate is connected with the other end of the insulating column;
a signal output interface connected with the annular current induction plate,
a frequency domain dielectric spectrum tester, the frequency domain dielectric spectrum tester comprising,
a voltage output terminal for inputting a high-frequency voltage signal to the high-voltage bushing via the signal input interface,
a current measuring terminal for obtaining a high-frequency current signal via the signal output interface,
and the test unit is connected with the voltage output end and the current output end.
2. The system of claim 1, wherein the annular current sensing plate is electrically connected to the current measuring end via a coaxial cable core, and a coaxial cable shielding layer is disposed on the coaxial cable core, and the coaxial cable core is connected to the annular base.
3. The system of claim 1, wherein the housing is a cylindrical structure.
4. The system of claim 1, wherein the housing has an opening at one end, and the tap interface is encapsulated in the opening.
5. A frequency domain dielectric response live testing system for a high voltage bushing according to claim 4, wherein a central axis of said tap connection interface is collinear with a central axis of said opening.
6. The system of claim 4, wherein the end screen connection interface is fitted with a sealing ring.
7. A frequency domain dielectric response live test system for a high voltage bushing according to claim 2, wherein the outer shield of the coaxial cable is grounded.
8. A frequency domain dielectric response live test system for a high voltage bushing according to claim 1, wherein the tap connection interface is parallel or collinear to the housing.
9. The system of claim 1, wherein the plurality of insulating columns are connected between the annular current sensing plate and the annular base to form a frusto-conical structure.
10. A frequency domain dielectric response live test system for a high voltage bushing according to claim 1, wherein the diameter of the annular current sensing plate is larger than the diameter of the annular base.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113791283A (en) * | 2021-08-17 | 2021-12-14 | 国网宁夏电力有限公司 | Frequency domain dielectric response live-line test system and method for high-voltage bushing |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113791283A (en) * | 2021-08-17 | 2021-12-14 | 国网宁夏电力有限公司 | Frequency domain dielectric response live-line test system and method for high-voltage bushing |
| CN113791283B (en) * | 2021-08-17 | 2024-09-06 | 国网宁夏电力有限公司 | Frequency domain dielectric response live test system and method for high-voltage sleeve |
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