CN112103060B

CN112103060B - Multi-stage excitation high-voltage proportion standard device

Info

Publication number: CN112103060B
Application number: CN202010788664.4A
Authority: CN
Inventors: 刘浩; 周峰; 殷小东; 刘俭; 袁建平; 陈松; 李志新
Original assignee: State Grid Jiangsu Electric Power Co ltd Marketing Service Center; State Grid Corp of China SGCC; China Electric Power Research Institute Co Ltd CEPRI
Current assignee: State Grid Jiangsu Electric Power Co ltd Marketing Service Center; State Grid Corp of China SGCC; China Electric Power Research Institute Co Ltd CEPRI
Priority date: 2020-08-07
Filing date: 2020-08-07
Publication date: 2022-07-01
Anticipated expiration: 2040-08-07
Also published as: CN112103060A

Abstract

The invention discloses a multi-stage excitation high-voltage proportion standard device and a preparation method thereof. The device includes: a main reference voltage device, the main reference voltage device comprising: a first Core1, a second Core2, and a third Core 3; wherein the second Core2 is located within the first Core; the third Core3 is positioned outside the first Core; a winding N2e wound around the first Core1 on a first side; a winding N1e wound around the first Core1 and the second Core2 at the same time on a first side; a winding N2 wound around the first Core1, the second Core2, and the third Core at the same time on a second side opposite to the first side; and a winding N1 wound outside the winding N2. The device has a high level of use voltage and accuracy.

Description

Multi-stage excitation high-voltage proportion standard device

Technical Field

The invention belongs to the technical field of electric power metering standard equipment, and particularly relates to a multistage excitation high-voltage proportion standard device.

Background

The voltage transformer is divided into field use and laboratory use. The field voltage transformer is called a power voltage transformer; the laboratory voltage transformer is used for calibrating the field voltage transformer and is called a standard voltage transformer. The accuracy of standard voltage transformers is at least one to two orders of magnitude higher than the accuracy of field voltage transformers. In addition, standard voltage transformers also have many levels of accuracy. The standard voltage transformer with the highest accuracy at present is called a power frequency voltage proportion standard device.

With the engineering application of the ultra-high voltage transmission technology, the accurate measurement of the ultra-high voltage power grid voltage becomes a key technical problem to be researched and solved urgently. Because of the insulation problem in the high-voltage field and the influence and restriction of various other electrical parameters by high voltage, the maximum working voltage of the current two-stage electromagnetic type power frequency voltage proportion standard is 10 KV.

Disclosure of Invention

In order to solve the above problems, the present invention provides a multi-stage excitation high voltage proportion standard device and a manufacturing method thereof, so as to solve the problems of low voltage and low accuracy of the current voltage proportion standard device.

In a first aspect, the present invention provides a multistage excitation high voltage proportion standard apparatus, including:

a main reference voltage device, the main reference voltage device comprising:

a first Core1, a second Core2, and a third Core 3; wherein the content of the first and second substances,

the second Core2 is located within the first Core;

the third Core3 is positioned outside the first Core;

a winding N2e wound around the first Core1 on a first side;

a winding N1e wound around the first Core1 and the second Core2 at the same time on a first side;

a winding N2 wound around the first Core1, the second Core2, and the third Core at the same time on a second side opposite to the first side;

and a winding N1 wound outside the winding N2.

Further, still include:

an auxiliary reference voltage device, the auxiliary reference voltage device comprising:

winding N1a and winding N2 a;

wherein the winding N1e and the winding N1a are connected in parallel with the winding N1;

the winding N2e is connected in series with the winding N2 a.

Further, the air conditioner is provided with a fan,

the winding N1e, the winding N1a and the winding N1 have the same number of turns;

the winding N2e, the winding N2a and the winding N2 have the same number of turns.

Further, the air conditioner is provided with a fan,

at a rated voltage of 500/√ 3kV for the standard device,

the first iron Core1 has an annular closed contour and is made of silicon steel;

the second iron Core2 has an annular closed contour and is made of permalloy 1J 85;

the third Core3 has an annular closed contour and is made of permalloy 1J 85.

Further, the air conditioner is provided with a fan,

in the winding N1, the layer width of the side far away from the first Core1 is gradually smaller than the layer width of the side close to the first Core 1;

in the winding N1e, the layer width on the side away from the first Core1 is gradually smaller than the layer width on the side away from the first Core 1.

Further, the air conditioner is provided with a fan,

the auxiliary standard voltage device further comprises: a fourth Core 4;

the first Core1, the second Core2, the third Core3 and the fourth Core4 are respectively connected to a grounding point.

Further, the air conditioner is characterized in that,

when the winding N1a is connected with a standard high voltage source and the winding N2 is connected with a standard voltage test instrument,

and determining the accuracy grade of the standard device to be 0.002 grade according to the voltage waveform acquired by the standard voltage test instrument and the voltage waveform provided by the standard high-voltage source.

In a second aspect, the present invention provides a method for manufacturing a multi-stage excitation high-voltage proportional standard device, including:

obtaining a first iron Core1, a second iron Core2 and a third iron Core3 which respectively have preset materials, cross-sectional shapes, cross-sectional areas and magnetic densities;

obtaining a lead wire with preset material, cross-sectional shape and cross-sectional area;

winding N2e with the number of turns of Y2 around the first side of the first Core1 by using a lead wire;

placing the second Core2 within the first Core 1;

on a first side, a winding N1e having a number of turns Y1 is wound with wire around the first Core1 and the second Core 2;

disposing a third Core3 outside the first Core 1;

winding N2 with the number of turns of Y2 is wound around the first iron Core1, the second iron Core2 and the third iron Core3 by using a lead on a second side opposite to the first side;

a winding N1 with Y1 turns is wound around the winding N2 with a wire.

Further, the air conditioner is provided with a fan,

when the winding N1 is wound, the layer width of the side far away from the first Core1 is gradually smaller than the layer width of the side close to the first Core 1;

when winding the winding N1e, the layer width on the side away from the first Core1 is gradually smaller than the layer width on the side close to the first Core 1.

Further, still include:

an auxiliary reference voltage acquisition device, the auxiliary reference voltage device comprising: a fourth Core4, a winding N1a, and a winding N2 a;

the winding N1e, the winding N1 and the winding N1a are connected in parallel;

winding N2a is connected in series with winding N2 e;

respectively connecting the first iron Core1, the second iron Core2, the third iron Core3 and the fourth iron Core4 with grounding points;

the head end and the tail end of the reserved winding N1a are respectively connected with a standard high-voltage source;

the head end and the tail end of the reserved winding N2 are respectively connected with a standard voltage test instrument.

The multistage excitation high-voltage proportion standard device provided by the invention has a four-iron-core six-winding structure, and realizes high-voltage excitation and low-voltage excitation respectively, so that the voltage grade of the voltage proportion standard device is improved, the excitation current is reduced, and the accuracy level of the voltage proportion standard device is improved.

Drawings

A more complete understanding of exemplary embodiments of the present invention may be had by reference to the following drawings in which:

fig. 1 is a schematic diagram of a multi-stage excitation high-voltage proportional standard device according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a multi-stage excitation principle of a multi-stage excitation high-voltage proportional standard device according to an embodiment of the present invention;

FIG. 3 is an equivalent circuit diagram of a multi-level excitation high voltage proportional standard device according to an embodiment of the present invention;

fig. 4 is a schematic view of a usage scenario of a multi-stage excitation high-voltage proportional standard device according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a high-voltage excitation double-stage voltage transformer in the prior art;

FIG. 6 is a schematic circuit of a high voltage excited two-stage voltage transformer in the prior art;

FIG. 7 is a schematic circuit of a low voltage excited two-stage voltage transformer in the prior art;

fig. 8 is a schematic circuit of a high-excitation three-stage voltage transformer in the prior art.

Detailed Description

The exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, however, the present invention may be embodied in many different forms and is not limited to the embodiments described herein, which are provided for complete and complete disclosure of the present invention and to fully convey the scope of the present invention to those skilled in the art. The terms used in the exemplary embodiments shown in the drawings are not intended to limit the present invention. In the drawings, the same units/elements are denoted by the same reference numerals.

Unless otherwise defined, terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Further, it will be understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense.

At present, the power frequency voltage proportion standard which is generally adopted internationally mainly comprises three types, namely resistance type, capacitance type and electromagnetic type. The resistive and capacitive standard devices are greatly affected by temperature, and are inferior to the electromagnetic standard devices in stability. The electromagnetic power frequency voltage proportion standard has the advantages of simple principle, convenient use, stability and reliability. In the electromagnetic structure, the two-stage standard transformer has high accuracy and good stability, and is most widely applied.

(1) Origin of double-stage mutual inductor

The two-stage principle was first proposed by h.b.brooks in 1922 and applied to two-stage current transformers. Compared with a single-stage iron core current transformer, the accuracy is greatly improved.

By means of reciprocity theorem, the concept of two-stage voltage transformer was first proposed in 1964 by cuskosky. And the voltage ratio required by the direct-reading audio device is designed and realized based on the concept. He does not elaborate and analyze the basic principles of the two-stage voltage transformer.

In 1968, the basic principle and structure of a two-stage voltage transformer were fully analyzed by t.a. deacon of the british National Physical Laboratory (NPL), and the basic schematic diagram and the principle circuit thereof are respectively shown in fig. 5 and 6.

Compared with the common single-stage voltage transformer, the error of the double-stage voltage transformer is about the product of the errors of the two single-stage transformers, so that the accuracy grade is greatly improved. Based on the principle, the low-voltage two-stage voltage transformer is developed by the T.A.deacon, and the theoretical feasibility is verified. However, the first-stage winding needs to penetrate through the second-stage winding, insulation among the windings is difficult to design, and the maximum use voltage of the two-stage voltage transformer at home and abroad is 10kV at present.

Because the highest voltage grade of the high-voltage excitation double-stage voltage transformer is only 10kV, in order to develop the double-stage voltage transformer with the voltage of more than 10kV, a low-voltage excitation structure is adopted. The low-voltage excitation structure is firstly proposed by experts such as Peng-Shing-Xiong of China North China electric power science institute, and a 35kV proportion standard device is successfully developed. In recent years, the China measurement institute has achieved 110kV/√ 3 kV.

A schematic circuit diagram of a two-stage voltage transformer with a low-voltage excitation structure is shown in fig. 7. The dotted line frame 1 is a two-stage main standard device, I and II are respectively a silicon steel sheet and a permalloy iron core, W1 and W2 are proportion primary windings and proportion secondary windings, and W3 is a low-voltage excitation winding. The dashed line frame 2 is an auxiliary excitation transformer with the same voltage, W4 and W5 are primary and secondary proportional windings, respectively, and W3 is W5, and W1 is W4.

In order to further improve the accuracy, a schematic diagram of a high-voltage excitation three-level voltage proportion standard device adopting a three-level structure is shown in fig. 8. An iron Core1 and a W1 high-voltage excitation winding form a first-stage voltage transformer, a Core2 and a W2 form a second-stage voltage transformer, and an iron Core3, a W3, a W4 and a W5 form a third-stage voltage transformer. In the three-level voltage proportion standard device, the first and second excitation windings W1 and W2 are high-voltage windings and are in a high-voltage excitation structure. Therefore, like the high-voltage excitation two-stage structure, the use voltage class disclosed in the literature is only 1kV at present due to the limitation of insulation.

A schematic diagram of a multi-stage excitation high-voltage proportional standard device according to an embodiment of the present invention is shown in fig. 2. The multistage excitation high-voltage proportion standard device comprises:

main reference voltage device P of left part₀And an auxiliary reference voltage device P of a right side portion_e；

Wherein the main standard voltage device P₀A first iron Core1, a second iron Core2 and a third iron Core3 are arranged;

main reference voltage device P₀The high-voltage excitation winding is also provided with a high-voltage proportional winding N1, a high-voltage excitation winding N1e, a low-voltage excitation winding N2e and a low-voltage proportional winding N2;

auxiliary reference voltage device P_eA fourth Core4, a winding N2a and a winding N1a are arranged;

the high-voltage proportional winding N1 and the high-voltage excitation winding N1e are connected with the winding N1a in parallel;

the winding N2a is connected with the low-voltage excitation winding N2e in series;

winding N1a is also used for connecting with a standard high-voltage source;

winding N2 is also used for connection to a standard voltage measuring instrument.

Specifically, 3 windings on the primary side (i.e., high voltage side): the number of turns of the winding N1, the winding N1e and the winding N1a is the same, and is a first number of turns Y1; the head ends of the taps of the 3 windings in parallel connection are respectively connected with the power supply ends of the standard high-voltage source, and the tail ends of the taps of the windings are respectively connected with the grounding point of the standard high-voltage source, so that the windings are respectively connected in parallel at two ends of the high-precision standard high-voltage source. The voltage across the standard high voltage source is denoted as U1.

Secondary side (i.e. low voltage side) 3 windings: the number of turns in winding N2, winding N2e, and winding N2a is also the same, and is the second number of turns Y2. Wherein, the winding N2a is a source U of a low-voltage excitation winding N2e_S'; winding N2a is connected in series with low voltage field winding N2 e. In the specific implementation, the head and tail ends of the winding N2a and the head and tail ends of the low-voltage excitation winding N2e are respectively connected end to end,a loop is formed.

Winding N2 is also used to connect a standard voltage measuring instrument, the voltage between its two ends being denoted as U2.

According to the relation between the multi-stage excitation structure and the number of winding turns, in theory, U2 should be equal to U1; in practice, there is a deviation and the level of accuracy of the multi-stage excitation high voltage proportional standard device is determined by comparing the deviations of U2 and U1.

As shown in fig. 2 and 3, the main reference voltage device P₀A multi-stage excitation is arranged, wherein the first stage excitation consists of a first iron Core1, a low-voltage excitation winding N2e and an auxiliary standard device Pe;

the second-stage excitation is composed of a second iron Core2 and a high-voltage excitation winding N1 e;

and the third-stage excitation is composed of a third Core3, a high-voltage proportional winding N1 and a low-voltage proportional winding N2.

Specifically, in the multi-stage excitation high voltage proportion standard device,

the low-voltage excitation winding N2e is Core1 excitation with excitation current I_oe；

The high-voltage excitation winding N1e is Core2 excitation with excitation current I₀₂；

The high-voltage winding N1 is excited by Core3 with exciting current I₀₃；

The high-voltage excitation winding N1a is Core4 excitation with excitation current I₀₁；

And has I₀₃<<I₀₂<<I₀₁(ii) a Wherein, I₀₁Is an exciting current I_0SAnd a load current I_0e' to be added.

As shown in fig. 1, at the lower end, the direction of the magnetic flux in the first Core1, the direction of the magnetic flux in the second Core2, and the direction of the magnetic flux in the third Core3 are the same.

During winding, in order to ensure that the magnetic flux directions of the windings wound on the side edges of the same iron core are consistent in the iron core and the magnetic flux directions of the windings wound on different side edges of the same iron core are consistent in the iron core, it is required to respectively determine that the winding directions of the windings are opposite according to the series or parallel relation between the windings, for example, the windings are wound in a clockwise direction or a counterclockwise direction.

Therefore, the multi-stage excitation high-voltage proportion standard device combines two methods of high-voltage excitation and low-voltage excitation, and therefore has high use voltage and good stability.

After the accuracy class is verified, further, as shown in fig. 4, the multi-stage high voltage excitation standard device (the first entity from the left side in fig. 4) of this embodiment is used as an etalon to be connected into a verification loop, and the 500kV series auxiliary voltage transformer to be tested (the second entity from the left side in fig. 4) is calibrated. In fig. 4, the third and fourth entities are series resonant power supplies, standard high voltage sources, from the left. The accuracy grade of the measured voltage transformer is determined by comparing the error between the measured value of the standard device and the measured value of the measured voltage transformer.

The main standard voltage device P of this embodiment is shown in a sectional view from the top view as shown in fig. 1₀The structure of (A) is as follows:

the first Core1, the second Core2 and the third Core3 are all round-angle rectangular annular cores;

the second Core2 is located inside the first Core1, and the second Core2 and the first Core1 are eccentrically arranged with respect to the axis a;

the first Core1, the second Core2, and the third Core3 are all disposed symmetrically with respect to the axis B;

a low-voltage excitation winding N2e is wound on the upper side edge of the first Core 1;

a high-voltage excitation winding N1e is wound on the upper side edge of the first Core1 and the upper side edge of the second Core 2;

the high voltage field winding N1e is isosceles trapezoid in cross section and has a long side on the side near the first Core1 and a short side on the other side/end away from the upper side of the first Core 1.

The third Core3 is positioned outside the first Core1 and the second Core 2;

the winding N2 is wound on the lower side edge of the first Core1, the lower side edge of the second Core2 and the upper side edge of the third Core 3;

the winding N1 is wound around the lower side of the first Core1, the lower side of the second Core2, the upper side of the third Core3 and the winding N2.

The winding N1 has an isosceles trapezoid cross-section, and has a long side on the side close to the core and a short side on the other side away from the core.

Unlike the conventional configuration in which the high-voltage winding N1e is surrounded by the high-voltage winding N1, the standard device of this embodiment is configured such that the high-voltage field winding N1e at the upper end and the high-voltage proportional winding N1 at the opposite lower end are substantially symmetrically arranged in space. The two high-voltage windings of the multi-stage excitation are basically symmetrical relative to the central line A, namely the two high-voltage windings are respectively arranged on two sides of the device, so that the insulation problem between the two high-voltage windings is ingeniously solved. Whereas the low voltage winding and N2 and N2e, which are nested within the high voltage winding N1 and the high voltage winding N1e, respectively, are low voltage windings, no insulation concerns need to be considered. Therefore, the standard device of this embodiment has a high use voltage and good stability.

In fig. 1, the third core and the first core have gaps of different sizes on 4 sides thereof, respectively. In specific implementation, because the insulation problem between the iron cores is solved, two adjacent iron cores can be arranged as close as possible, so that the gap between the two iron cores is as small as possible;

similarly, because the problem of insulation between adjacent windings has been solved, two adjacent windings can be disposed as close as possible so that the gap between the two is as small as possible. On the one hand, the structure compactness of the multi-stage excitation assembly can be improved, on the other hand, the length of the wire used by each winding can be reduced, the size of each iron core can be reduced, and raw materials are saved.

It should be understood that each rounded rectangular ring core may also be a closed racetrack ring core (i.e., two horseshoe-shaped segments joined at an opening) or a circular ring core.

The auxiliary standard voltage device Pe is a conventional voltage transformer, directly adopts the structure in the prior art, and is not additionally specially designed.

In specific implementation, the relative position relationship between the main standard voltage device and the auxiliary standard voltage device is not limited; the first ends and the tail ends of the two windings of the auxiliary standard voltage device are connected with the first ends and the tail ends of the windings of the corresponding main standard voltage device according to the specified circuit connection relationship.

In measuring the test accuracy, the high-voltage proportional winding N1a of the auxiliary standard voltage device is connected with a tested high-voltage source (not shown in FIG. 2); the low-voltage proportional winding N2 of the main standard voltage device is connected with a high-precision voltage measuring instrument (not shown in fig. 2); and respectively determining the voltage amplitude and the phase accuracy by comparing the waveform of the high-voltage source to be measured with the voltage waveform obtained by the high-precision voltage measuring instrument.

The accuracy grade is the most important technical parameter of the voltage proportional standard device. In the following, referring to fig. 3, the error of the multi-stage excitation voltage proportion standard device is theoretically deduced and analyzed, so as to determine the accuracy level thereof. The variables and physical meanings in figure 3 are as set forth in table 1 below:

TABLE 1 variables and physical meanings

1) First order error

According to FIG. 3, the first stage current I₀₁Involving exciting currents

And load current

The first order error is therefore determined by the excitation error

And load error

And (4) forming.

According to the error definition of the voltage transformer, the first stage excitation error

Is composed of

In view of

And

it is possible to obtain:

load error

Can be expressed as:

in the formula (4), the reaction mixture is,

2) second order error

Primary side voltage of the second stage

Equal to the impedance of the first stage voltage transformer at winding N1a

Impedance of winding N2a (converted to primary side)

And total voltage drop across the impedance of winding N2e (translated to the primary side):

due to the fact that

Then there is

Then the excitation error of the second stage is obtained

3) Error of the third stage

Primary side voltage of the second stage

Equal to the impedance of winding N1e

Pressure drop over:

excitation error of the second stage

Can be expressed as:

4) overall error, and the like

The total error of the multi-level voltage scaling standard as a whole

Can be expressed as:

in summary, equation (8) can be further expressed as:

by comparing the formulas (2), (4), (6), (7) and (9), the results can be obtained

That is, the total error of the multi-stage standard device is equal to the product of the excitation error of each stage.

For example, when the excitation errors of the first, second, and multistage are all 1%, the total error is 1% × 1% × 1 × 10%^-6Thereby greatly reducing the error.

It should be understood that, at this time, the load error of the first stage

Excitation error from the first stage

The orders of magnitude are equivalent; here, when the overall error is estimated, theIt is ignored and the magnitude of the resulting total error remains unchanged.

When designing a 500/√ 3kV multistage excitation voltage proportion standard device which is consistent with the multistage excitation principle and structure and has a transformation ratio of 5000 as shown in FIG. 1 and FIG. 2, the method comprises the following steps:

(1) parameter calculation

The first iron core is made of silicon steel sheets with large magnetic flux.

Firstly, a nominal voltage U is determined_NAt 500/√ 3kV, the operating magnetic density B of the first core is 1.0T.

Under the premise of determining the working magnetic density, the larger the turn potential is, the larger the sectional area of the iron core is, and the excitation error caused by the increase of the excitation admittance is increased. However, if the turn potential is too small, the winding wound around the core needs more turns, and at this time, the internal resistance of the primary winding increases, and the excitation error increases accordingly.

And after comprehensively considering various factors such as the shape and the area of the cross section of the iron core, error performance, the number of turns of the primary winding and the like, determining the turn potential and the corresponding number of turns.

Specifically, 500kV takes turn potential of about 2V/turn; and the number of turns is determined based on the turn potential.

Specifically, the number of turns of the primary winding of the first iron core is selected to be N₁＝N_1e150000, turn potential:

in this case, the number of turns of the secondary winding is 30 turns, and the number of turns of the primary winding is divided by the transformation ratio 5000.

Further, according to the formula e of turn potential_t＝4.44fBSk×10^-4Wherein, in the step (A),

k is the core lamination coefficient, and 0.99 is taken;

f is the power frequency voltage frequency and is 50 Hz;

b is working magnetic density;

s is the cross-sectional area of the iron core lamination;

the cross-sectional shape of the first core was determined to be circular, and the cross-sectional area of the first core was calculated to be 87.36cm²。

The second iron core is made of permalloy 1J85, and the rated magnetic flux is 0.45T; determining the cross section of the second iron core to be square, and calculating the cross section of the second iron core to be S-6 cm²。

Selecting permalloy 1J85 as the third core, and setting the rated magnetic flux to be 0.1T; determining the cross-sectional shape of the third iron core to be square, and calculating the cross-sectional area of the third iron core to be 1.6cm²。

The fourth iron core is made of the same material, rated magnetic flux, shape and sectional area as the first iron core.

TABLE 2 iron core parameters

	Core1	Core2	Core3	Core4
					Iron core material	Silicon steel sheet	Permalloy 1J85	Permalloy 1J85	Silicon steel sheet
Cross-sectional shape	Circular shape	Square shape	Square shape	Circular shape
					Cross sectional area	87.36cm²	6cm²	1.6cm²	87.36cm²
Rated magnetic flux density	1.0T	0.45T	0.1T	1.0T

Permalloy refers to an iron-nickel alloy, and has a high initial magnetic permeability. The permalloy is characterized by high low-intensity magnetic permeability, and the saturation magnetic induction intensity of the permalloy is generally between 0.6 and 1.0T. Initial permeability refers to the permeability at "no load", and permeability under different conditions (different magnetic fields, different frequencies, and different temperatures) is generally less than the initial permeability.

The standard device of this embodiment is made as follows:

1) preparing materials:

respectively customizing 3 iron cores with preset materials, cross-sectional shapes, cross-sectional areas and rated magnetic densities;

respectively preparing leads with preset materials, cross-sectional shapes and cross-sectional areas;

the method comprises the steps of obtaining an auxiliary standard excitation device which has a preset transformation ratio of 5000 and a preset use voltage level of 500/V3 kV and comprises a fourth iron Core4, a winding N1a and a winding N2 a;

2) and winding the same

Winding a first-stage low-voltage excitation winding N2e around the first side of the Core1 to obtain a first-stage low-voltage excitation winding N2e with the number of turns of Y2;

embedding a Core2 within a Core 1;

winding a second stage high voltage field winding N1e around a first side of the Core1 and a first side of the Core2 to obtain a high voltage field winding N1e with Y1 turns, wherein the first side of the Core1 is adjacent to the first side of the Core 2; that is, the second-stage high-voltage excitation winding N1e is wound on the first side of the Core1 and the first side of the Core2 at the same time;

fixing the Core3 at one side outside the Core 1;

winding a second stage low voltage proportional winding N2 around a second side of the Core1, a second side of the Core2, and a first side of the Core3, resulting in a second stage low voltage proportional winding N2 having Y2 turns, wherein the second and first sides of the Core1 are opposite sides, the second and first sides of the Core2 are opposite sides, and the first side of the Core3 is adjacent to the second side of the Core 1; that is, a second stage low voltage proportional winding N2 is wound around the second side of Core1, the second side of Core2 and the first side of Core3 at the same time;

and a multi-stage high-voltage proportional winding N1 is wound around the second side of the Core1, the second side of the Core2, the first side of the Core3 and a multi-stage low-voltage proportional winding N2, so that the multi-stage high-voltage proportional winding N1 with the number of turns of Y1 is obtained, namely, the high-voltage proportional winding N1 is simultaneously wound around the second side of the Core1, the second side of the Core2, the first side of the Core3 and the multi-stage low-voltage proportional winding N2.

Specifically, as shown in fig. 1, the winding gradually decreases from the inside to the outside, the number of turns, and the layer width. Meanwhile, the closer the distance from the iron core, the lower the voltage on the winding; the farther from the core, the higher the voltage on the winding; therefore, by controlling the number of turns or the width, a sufficiently safe insulation distance is achieved.

3) Wiring

Connecting a second-stage high-voltage excitation winding N1e, a high-voltage proportional winding N1 and a winding N1a in parallel;

connecting the winding N2a in series with a first stage low voltage excitation winding N2 e;

and the head and tail ends of the reserved third-stage low-voltage proportional winding N2 are respectively connected with a standard voltage test instrument.

The Core1, the Core2, the Core3 and the Core4 are equipotentially grounded.

Compared with the traditional structure, the Core3 is positioned at the lower side, and the high-voltage excitation winding N1e and the high-voltage proportional winding N1 are in an up-and-down symmetrical structure, so that the problem that the two-stage voltage proportional standard device is difficult to apply at a voltage level of more than 10kV for a long time is solved.

As shown in fig. 4, the multi-stage excitation voltage proportional standard device of the embodiment is connected to a standard high voltage source and a standard voltage test instrument, respectively, and error calibration is performed thereon.

Table 3 lists the final error calibration results. The accuracy grade of the multi-stage excitation voltage proportion standard device is 0.002 grade. The multistage excitation voltage proportion standard device improves an accuracy level by referring to the domestic highest 0.005 level of the current 500/V3 kV voltage proportion standard device.

TABLE 3 error calibration results

The invention has been described above by reference to a few embodiments. However, other embodiments of the invention than the one disclosed above are equally possible within the scope of the invention, as would be apparent to a person skilled in the art from the appended patent claims.

Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to "a// the [ device, component, etc ]" are to be interpreted openly as at least one instance of a device, component, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.

Claims

1. A multi-stage excitation high-voltage proportional standard device is characterized by comprising:

a main reference voltage device, the main reference voltage device comprising:

the second Core2 is located within the first Core;

the third Core3 is positioned outside the first Core;

a winding N2e wound around the first Core1 on a first side;

a winding N1 wound outside the winding N2;

winding N1a and winding N2 a;

the winding N2e is connected in series with the winding N2 a;

the winding N2e, the winding N2a and the winding N2 have the same number of turns;

at a rated voltage of 500/√ 3kV for the standard device,

the third Core3 has an annular closed contour and is made of permalloy 1J 85;

in the winding N1, the layer width of the side far away from the first Core1 is gradually smaller than the layer width of the side near the first Core 1;

in the winding N1e, the layer width of the side far away from the first Core1 is gradually smaller than the layer width of the side far away from the first Core 1;

the auxiliary standard voltage device further comprises: a fourth Core 4;

the first iron Core1, the second iron Core2, the third iron Core3 and the fourth iron Core4 are respectively connected with a grounding point;

2. A manufacturing method of a multi-stage excitation high-voltage proportion standard device is characterized by comprising the following steps:

winding a winding N2e with Y2 turns around the first side of the first Core1 by using a lead wire;

placing the second Core2 inside the first Core 1;

winding N1e with a number of turns Y1 around the first Core1 and the second Core2 with wire on a first side;

disposing a third Core3 outside the first Core 1;

a winding N1 with Y1 turns is wound around the winding N2 with a wire.

3. The method of manufacturing according to claim 2,

4. The method of manufacturing according to claim 2, further comprising:

the winding N1e, the winding N1 and the winding N1a are connected in parallel;

winding N2a is connected in series with winding N2 e;