CN107271740A - The preparation method of high tension voltage sampling apparatus - Google Patents
The preparation method of high tension voltage sampling apparatus Download PDFInfo
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- CN107271740A CN107271740A CN201710412483.XA CN201710412483A CN107271740A CN 107271740 A CN107271740 A CN 107271740A CN 201710412483 A CN201710412483 A CN 201710412483A CN 107271740 A CN107271740 A CN 107271740A
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- cavity
- high pressure
- resistance
- voltage
- sampling
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R3/00—Apparatus or processes specially adapted for the manufacture or maintenance of measuring instruments, e.g. of probe tips
Abstract
The invention discloses a kind of preparation method of high tension voltage sampling apparatus, embedding cavity including both ends open, it is respectively arranged on 2 operating circuit cavitys at embedding cavity two ends, stretch into embedding cavity and 2 operating circuit cavitys surround insulation fiberglass sleeve in space, high pressure divider resistance in insulation fiberglass sleeve, it is sheathed on the high-voltage metallized thin-film capacitor on insulation fiberglass sleeve, located at insulation fiberglass sleeve two ends and 2 metallic shield electrodes being connected respectively with high pressure divider resistance two ends, insulating cylinder on the external side face of encapsulation cavity, 2 resistance sampling wires being electrically connected with high pressure divider resistance two ends, 2 capacitance electrode wires being electrically connected with high-voltage metallized thin-film capacitor two ends.The present invention have size is small, sensitivity is high, small power consumption the characteristics of.
Description
Technical field
The present invention relates to power network high pressure sample devices technical field, more particularly, to a kind of small volume, sensitivity height, energy consumption
The preparation method of low high tension voltage sampling apparatus.
Background technology
At present, in high-tension line (6.6kV, 10kV, 20kV, 35kV etc.), electronic type voltage transformer, power measurement instrument
The products such as table, high-voltage electric energy meter, its operation principle all includes voltage sample and high pressure power-supply circuit, wherein voltage sample mode master
It is divided into two kinds of capacitance partial pressure and electric resistance partial pressure.Capacitance partial pressure major defect is that sampling precision is not high, and temperature drift is larger, electric resistance partial pressure
Sample mode sampling precision is high, but to will also result in sampling precision impacted for stray capacitance；Power-supply circuit is typically sampled using high pressure
Circuit, high pressure is dropped to by capacitance partial pressure mode the low voltage for being available for power circuit to work and carries out power taking.
As shown in figure 1, high pressure sample circuit is main by divider resistance R1, R2, derided capacitors C1, C2, power module and work
Make circuit module composition.It is relatively low signal voltage that divider resistance R1, R2, which are responsible for high voltage partial pressure, to be supplied to operating circuit
Sampled；Low voltage is separated from high tension loop by electric capacity C1, C2 bleeder circuit constituted, then by power module is work
Make the DC working powers needed for circuit module is provided.
High pressure Sampling device embedding structure chart as shown in Figure 2, in high voltage sampling, undertakes the device of most of high pressure
Mainly there are resistance R1 and electric capacity C1, two components are the larger devices of volume, due to needing by high-voltage isulation performance test
In the experiment such as pressure-resistant, partial discharge, two high tension apparatus are needed by vacuum encapsulation in closed space.Wherein, C1 is generally
One or more capacitance series.
Because ac high-voltage in the electric field that two interpolars are produced is uneven, voltage measurement can be made to produce larger error, especially
It is needing the occasion of accurate measurement, such as：On electronic type voltage transformer, the product such as direct-type high-voltage electric energy meter, to solve this
A kind of problem, existing improvement mode such as figure institute 3 shows：Sample resistance is placed in electronic ceramics pipe and embedding, in electronic ceramics pipe
Outer periphery uniform etching goes out multigroup resistance pressure-dividing network and is connected in parallel between the two poles of the earth of ac high-voltage.So as to ensure sampling resistor week
It is uniform to enclose electric field.But, the method cost is higher.
Existing electric resistance partial pressure voltage sample mode is primarily present following shortcoming：
Divider resistance and derided capacitors are connected across the interpolar of high-tension line two respectively as two independent elements, shared
Space is big, is unfavorable for the miniaturization of product, meanwhile, manufacture, assembly technology is complicated, increases manufacturing cost.
As shown in Fig. 2 electric resistance partial pressure sampling is influenceed due to non-uniform electric between its high-low pressure on resistance sampling precision
It is larger, it can increase higher cost in outer lateral erosion resistor network in the method for uniform sampling resistance surrounding electric field.
In order to improve the sampling precision of divider resistance, resistance R1 two ends usually require to carry out electric field shielding, due to electric capacity C1
Presence, cause space structure narrow, resistance R1 shielding is higher to technological requirement.
The content of the invention
The goal of the invention of the present invention is that power network high pressure sample devices volume of the prior art is big, sensitivity in order to overcome
A kind of preparation method of low, high energy consumption the not enough high tension voltage sampling apparatus low there is provided small volume, sensitivity height, energy consumption.
To achieve these goals, the present invention uses following technical scheme：
A kind of preparation method of high tension voltage sampling apparatus, includes the embedding cavity of both ends open, is respectively arranged on encapsulation cavity
2 operating circuit cavitys at body two ends, stretch into embedding cavity and 2 operating circuit cavitys surround insulation glass set in space
Pipe, the high pressure divider resistance in insulation fiberglass sleeve is sheathed on the high-voltage metallized thin-film capacitor on insulation fiberglass sleeve,
Located at insulation fiberglass sleeve two ends and 2 metallic shield electrodes being connected respectively with high pressure divider resistance two ends, located at encapsulation cavity
Insulating cylinder on external side face, 2 resistance sampling wires being electrically connected with high pressure divider resistance two ends, with high-voltage metallized
2 capacitance electrode wires that thin-film capacitor two ends are electrically connected, 2 metallic shield electrodes respectively with 2 operating circuit cavitys
It is tightly connected, the cavity by vacuumizing is provided between embedding cavity and high-voltage metallized thin-film capacitor；
Comprise the following steps：
High-voltage metallized thin-film capacitor is wound on insulation fiberglass sleeve by (1-1)；
High tension voltage sampling resistor two ends are fixedly mounted on insulation fiberglass sleeve by (1-2) using 2 metallic shield electrodes
In the cavity in axle center, high pressure divider resistance two ends are electrically connected with 2 resistance sampling wires respectively, by 2 capacitance electrode wires point
It is not connected with high-voltage metallized thin-film capacitor two ends, obtains integral type resistance capacitance sub-assembly；
Integral type resistance capacitance sub-assembly is installed in encapsulation cavity body by (1-3), and 2 operating circuit cavitys are installed into filling
Seal on cavity, is size is fixedly mounted in one end of embedding cavity, and the other end is vacuum encapsulation end；
After (1-4) embedding is finished, 2 resistance sampling wires and 2 capacitance electrode wires are drawn and operating circuit is connected；
(1-5) crimps insulating cylinder on the external side face of encapsulation cavity.
High-voltage metallized thin-film capacitor is wound on insulation cavity pipe, then high pressure sampling resistor is placed on into electricity by the present invention
In the cavity for holding axle center, integrate the sampling of high-tension resistive partial pressure and capacitance partial pressure current-taking function, tradition is solved well
Shortcoming in the sampling of high-tension resistive partial pressure, has following points advantage：
1st, high pressure sampling element embedding volume significantly reduces；
2nd, high-voltage metallized thin-film capacitor monomer as shown in figure 4, metallized film be by a plurality of film for being coated with metal around
System is formed, can with the equivalent series connection as multiple electric capacity, multiple metallized film capacitors are monomer series-connected connect can be equivalent to it is many
The series connection of individual electric capacity, whole electric resistance partial pressure voltage sampling element can be equivalent to shown in Fig. 5 by multiple capacitive divider network bags
Be trapped among around resistance sampling, form with resistance pressure-dividing network identical uniform electric field effect, simultaneously because electric capacity is not active
Loss, reduces sampling energy consumption.
Preferably, the insulating cylinder is provided with the SOI full skirt that several are arranged in order along insulating cylinder bearing of trend,
The width of the cross section of SOI full skirt diminishes successively from the bottom to top.
Preferably, high pressure divider resistance is integral type high pressure sampling resistor or several high pressure sampling resistor connection in series-parallel groups
Into.
Preferably, the end of 2 metallic shield electrodes towards high pressure divider resistances is all provided with fluted, high pressure divider resistance
Two ends are stretched into 2 grooves, and 2 bottom portion of groove are respectively provided with the through hole through 2 resistance sampling wires.
Preferably, high-voltage metallized thin-film capacitor is in series by several monomer electric capacity, each monomer electric capacity by
The film winding for being coated with some metal films is formed.
Preferably, 2 operating circuit cavitys are rounded, it is recessed in the middle part of 2 operating circuit cavitys to inner side.
Therefore, the present invention has the advantages that：The physical dimension of high pressure sampling is significantly reduced, high-voltage metallized is thin
Membrane capacitance is wound on outside sampling resistor, plays a part of shielding sampling resistor electric field, electric capacity uniform gradient, which declines, to be also played
The effect of even sampling resistor surrounding electric field, improves detection sensitivity；Reduce cost and energy consumption.
Brief description of the drawings
Fig. 1 is a kind of electric resistance partial pressure voltage sample theory diagram of prior art；
Fig. 2 is a kind of high pressure Sampling device embedding structure chart of prior art；
Fig. 3 is that a kind of resistance pressure-dividing network of prior art realizes the schematic diagram of uniform electric field；
Fig. 4 is a kind of molding structure schematic diagram of monomer electric capacity of the present invention；
Fig. 5 is a kind of electric resistance partial pressure sampling isoboles of the present invention；
Fig. 6 is a kind of sectional view of the present invention；
Fig. 7 to Fig. 9 is a kind of Making programme schematic diagram of the present invention.
In figure：High pressure divider resistance 1, insulation fiberglass sleeve 2, high-voltage metallized thin-film capacitor 3, metallic shield electrode 4, filling
Seal cavity 5, operating circuit cavity 6, film 7, SOI full skirt 8, insulating cylinder 9, resistance sampling wire 10, capacitance electrode wire
11st, metal film 12, equivalent capacity distributed network 13, electronic ceramics pipe 14.
Embodiment
The present invention will be further described with reference to the accompanying drawings and detailed description.
Embodiment as shown in Figure 6 is a kind of preparation method of high tension voltage sampling apparatus, includes the embedding of both ends open
Cavity 5, is respectively arranged on 2 operating circuit cavitys 6 at embedding cavity two ends, stretches into embedding cavity and 2 operating circuit cavity institutes
The insulation fiberglass sleeve 2 in space is surrounded, the high pressure divider resistance 1 in insulation fiberglass sleeve is sheathed on insulation glass set
High-voltage metallized thin-film capacitor 3 on pipe, located at insulation fiberglass sleeve two ends and be connected respectively with high pressure divider resistance two ends 2
Individual metallic shield electrode 4, the insulating cylinder 9 on the external side face of encapsulation cavity, 2 be electrically connected with high pressure divider resistance two ends
Individual resistance sampling wire 10,2 capacitance electrode wires being electrically connected with high-voltage metallized thin-film capacitor two ends, 11,2 gold
Category bucking electrode is tightly connected with 2 operating circuit cavitys respectively, is provided between embedding cavity and high-voltage metallized thin-film capacitor
By the cavity vacuumized；
Comprise the following steps：
High-voltage metallized thin-film capacitor is wound on insulation fiberglass sleeve by (1-1), as shown in fig. 7, high metal film
Electric capacity can be composed in series by 4 monomer electric capacity；
High tension voltage sampling resistor two ends are fixedly mounted on insulation fiberglass sleeve by (1-2) using 2 metallic shield electrodes
In the cavity in axle center, high pressure divider resistance two ends are electrically connected with 2 resistance sampling wires respectively, by 2 capacitance electrode wires point
It is not connected with high-voltage metallized thin-film capacitor two ends, obtains integral type resistance capacitance sub-assembly；
High-voltage metallized thin-film capacitor monomer is as shown in figure 4, metallized film is by a plurality of film winding for being coated with metal
Form, can with the equivalent series connection as multiple electric capacity, multiple metallized film capacitors are monomer series-connected connect can be equivalent to it is multiple
The series connection of electric capacity, whole electric resistance partial pressure voltage sampling element can be equivalent to the equivalent capacity distributed network 13 shown in Fig. 5, by many
Individual capacitive divider network is enclosed in around resistance sampling, form with resistance pressure-dividing network identical uniform electric field effect, simultaneously
Because electric capacity does not have active loss, sampling energy consumption is reduced.
The resistor assembly high tension voltage constituted by integrated high pressure sampling resistor or by multiple high pressure sampling resistor connection in series-parallel
In sampling resistor, the cavity that high metal thin-film capacitor axle center is fixedly mounted on by metallic shield electrode, as shown in figure 8, two
End connects the two poles of the earth and the fixation in high tension voltage loop respectively, and 2 capacitance electrode wires and 2 resistance sampling wires are led into 2
Outside metallic shield electrode；
Integral type resistance capacitance sub-assembly is installed in encapsulation cavity body by (1-3), and 2 operating circuit cavitys are installed into filling
Seal on cavity, as shown in figure 9, is size is fixedly mounted in one end of embedding cavity, the other end is vacuum encapsulation end；
After (1-4) embedding are finished, 2 capacitance electrode wires and 2 resistance sampling wires are drawn and operating circuit is connected,
2 capacitance electrode wires and 2 capacitance electrode wires at high tension voltage sampling apparatus two ends are all connected with operating circuit, operating circuit
It is connected with high-voltage line to be measured, so as to carry out high tension voltage sampling.
Or, by 1 capacitance electrode wire of high tension voltage sampling apparatus one end and 2 capacitance electrode wire connection work
Circuit, high-voltage line is connected by 1 capacitance electrode wire of the high tension voltage sampling apparatus other end and 2 capacitance electrode wires, from
And carry out high tension voltage sampling.
(1-5) crimps insulating cylinder on the external side face of encapsulation cavity.
Insulating cylinder is provided with 7 SOI full skirts 8 for being arranged in order along insulating cylinder bearing of trend, SOI full skirt it is transversal
The width in face diminishes successively from the bottom to top, and obtained high tension voltage sampling apparatus is as shown in Figure 6.Each SOI full skirt is set
Purpose is to climb electric spacing to increase.
High pressure divider resistance is that integral type high pressure sampling resistor or multiple high pressure sampling resistor connection in series-parallel are constituted.
The end of 2 metallic shield electrodes towards high pressure divider resistances is all provided with fluted, and high pressure divider resistance two ends stretch into 2
In individual groove, 2 bottom portion of groove are respectively provided with the through hole through 2 resistance sampling wires.
High-voltage metallized thin-film capacitor is in series by 4 monomer electric capacity, and each monomer electric capacity is by plating as shown in Figure 4
The coiling of film 7 for having 6 metal films 12 is formed.2 operating circuit cavitys are rounded, in the middle part of 2 operating circuit cavitys to
Inner side is recessed.In Fig. 3, including electronic ceramics pipe 14.
It should be understood that the present embodiment is only illustrative of the invention and is not intended to limit the scope of the invention.In addition, it is to be understood that
Read after the content of the invention lectured, those skilled in the art can make various changes or modifications to the present invention, these etc.
Valency form equally falls within the application appended claims limited range.
Claims (6)
1. a kind of preparation method of high tension voltage sampling apparatus, it is characterized in that, include the embedding cavity (5) of both ends open, respectively
2 operating circuit cavitys (6) located at embedding cavity two ends, stretch into embedding cavity and 2 operating circuit cavitys surround space
Interior insulation fiberglass sleeve (2), the high pressure divider resistance (1) in insulation fiberglass sleeve is sheathed on insulation fiberglass sleeve
High-voltage metallized thin-film capacitor (3), located at insulation fiberglass sleeve two ends and be connected respectively with high pressure divider resistance two ends 2
Metallic shield electrode (4), the insulating cylinder (9) on the external side face of encapsulation cavity, is electrically connected with high pressure divider resistance two ends
2 resistance sampling wires (10), 2 capacitance electrode wires being electrically connected with high-voltage metallized thin-film capacitor two ends
(11), 2 metallic shield electrodes are tightly connected with 2 operating circuit cavitys respectively, embedding cavity and high-voltage metallized thin-film electro
The cavity by vacuumizing is provided between appearance；
Comprise the following steps：
High-voltage metallized thin-film capacitor is wound on insulation fiberglass sleeve by (1-1)；
High tension voltage sampling resistor two ends are fixedly mounted on insulation fiberglass sleeve axle center by (1-2) using 2 metallic shield electrodes
Cavity in, high pressure divider resistance two ends are electrically connected with 2 resistance sampling wires respectively, by 2 capacitance electrode wires respectively with
High-voltage metallized thin-film capacitor two ends are connected, and obtain integral type resistance capacitance sub-assembly；
Integral type resistance capacitance sub-assembly is installed in encapsulation cavity body by (1-3), and 2 operating circuit cavitys are installed into encapsulation cavity
On body, is size is fixedly mounted in one end of embedding cavity, and the other end is vacuum encapsulation end；
After (1-4) embedding is finished, 2 resistance sampling wires and 2 capacitance electrode wires are drawn and operating circuit is connected；
(1-5) crimps insulating cylinder on the external side face of encapsulation cavity.
2. the preparation method of high tension voltage sampling apparatus according to claim 1, it is characterized in that, the insulating cylinder is provided with
Several SOI full skirts (8) being arranged in order along insulating cylinder bearing of trend, the width of the cross section of SOI full skirt by it is lower extremely
On diminish successively.
3. the preparation method of high tension voltage sampling apparatus according to claim 1, it is characterized in that, high pressure divider resistance is one
Body formula high pressure sampling resistor or several high pressure sampling resistor connection in series-parallel composition.
4. the preparation method of high tension voltage sampling apparatus according to claim 1, it is characterized in that, 2 metallic shield electrodes
It is all provided with towards the end of high pressure divider resistance fluted, high pressure divider resistance two ends are stretched into 2 grooves, 2 groove-bottom parts
The through hole through 2 resistance sampling wires She You be used for.
5. the preparation method of high tension voltage sampling apparatus according to claim 1, it is characterized in that, high-voltage metallized thin-film electro
Appearance is in series by several monomer electric capacity, and each monomer electric capacity is by film (7) coiling for being coated with some metal films (12)
Form.
6. the preparation method of the high tension voltage sampling apparatus according to claim 1 or 2 or 3 or 4 or 5, it is characterized in that, 2
Operating circuit cavity is rounded, is recessed in the middle part of 2 operating circuit cavitys to inner side.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710412483.XA CN107271740B (en) | 2017-06-02 | 2017-06-02 | Manufacturing method of high-voltage sampling device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710412483.XA CN107271740B (en) | 2017-06-02 | 2017-06-02 | Manufacturing method of high-voltage sampling device |
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| Publication Number | Publication Date |
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| CN107271740A true CN107271740A (en) | 2017-10-20 |
| CN107271740B CN107271740B (en) | 2020-04-14 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107870260A (en) * | 2017-12-15 | 2018-04-03 | 武汉东硕电气有限公司 | One kind metering takes can integrated high-accuracy voltage sensor |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN87214780U (en) * | 1987-10-31 | 1988-04-27 | 董家右 | High voltage meter |
| EP0980003A1 (en) * | 1998-08-12 | 2000-02-16 | Trench Switzerland AG | RC voltage divider |
| JP2003059738A (en) * | 2001-08-16 | 2003-02-28 | Toko Electric Corp | Voltage transformer |
| CN101074972A (en) * | 2006-05-15 | 2007-11-21 | 北京瑞恒超高压电器研究所 | Capacitance mask resistance sensor |
| CN201430071Y (en) * | 2009-04-10 | 2010-03-24 | 欧阳南尼 | Capacitance shield voltage divider |
-
2017
- 2017-06-02 CN CN201710412483.XA patent/CN107271740B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN87214780U (en) * | 1987-10-31 | 1988-04-27 | 董家右 | High voltage meter |
| EP0980003A1 (en) * | 1998-08-12 | 2000-02-16 | Trench Switzerland AG | RC voltage divider |
| JP2003059738A (en) * | 2001-08-16 | 2003-02-28 | Toko Electric Corp | Voltage transformer |
| CN101074972A (en) * | 2006-05-15 | 2007-11-21 | 北京瑞恒超高压电器研究所 | Capacitance mask resistance sensor |
| CN201430071Y (en) * | 2009-04-10 | 2010-03-24 | 欧阳南尼 | Capacitance shield voltage divider |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107870260A (en) * | 2017-12-15 | 2018-04-03 | 武汉东硕电气有限公司 | One kind metering takes can integrated high-accuracy voltage sensor |
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| CN107271740B (en) | 2020-04-14 |
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