CN202363232U

CN202363232U - Dry-type direct current voltage transformer

Info

Publication number: CN202363232U
Application number: CN201120495876XU
Authority: CN
Inventors: 黄德祥; 曹东明; 刘彬; 潘淳; 于海波
Original assignee: NR Electric Co Ltd; Changzhou NR Electric Power Electronics Co Ltd
Current assignee: NR Electric Co Ltd; Changzhou NR Electric Power Electronics Co Ltd
Priority date: 2011-12-03
Filing date: 2011-12-03
Publication date: 2012-08-01
Anticipated expiration: 2021-12-03

Abstract

The utility model relates to a dry-type direct current voltage transformer, which comprises hollow compound insulators, a primary bus wiring cable, a shielding ring, dry-type insulation media, voltage share resistor strings and a voltage equalizing capacitor, wherein the voltage share resistor strings are coiled on the outer wall of the voltage equalizing capacitor to form a resistance and capacitance measurement unit; the primary bus wiring cable is connected to the voltage share resistor strings; the shielding ring is arranged at the upper end of the voltage equalizing capacitor; the voltage equalizing capacitor and the voltage share resistors are assembled in the hollow compound insulator; and the dry-type insulation media are filled in a space between the resistance and capacitance measurement unit and the hollow compound insulator. The utility model provides a simple and reliable dry-type insulation structure and a voltage measurement scheme; insulation media, such as oil and gas are not required for monitoring and maintaining; the dry-type direct current voltage transformer can be used for measuring high direct current voltage of various voltage levels; and the dry-type direct current voltage transformer has the advantages of stable and reliable insulation performance, high measurement accuracy, running safety and the like.

Description

The dry type DC voltage transformer

Technical field

The utility model belongs to power transmission and transforming equipment High-Voltage Electrical Appliances field; The DC voltage transformer that relates to a kind of electric resistance partial pressure; Its dc high voltage that is applicable to 50kV, 500kV, 800kV electric pressure circuit is measured, and is one of key equipment that guarantees the HVDC transmission system reliability service.

Background technology

The high-voltage dc voltage instrument transformer has important function to the safe and stable operation that guarantees HVDC transmission system; Present built in China and the dc voltage measurement equipment that in the high voltage direct current transmission project of building, uses are imported product; Operating experience in recent years shows that similar imported product not only costs an arm and a leg, and after-sale service is untimely; Oil-filled, the gas mode of the many employings of its insulation system; Also there is defective in complicacy, and is not easy to safeguard, can not satisfy the demand of direct current electric transmission and transformation system operation steady in a long-term fully.

At present, several kinds of modes below the general employing of dc voltage measurement: electromagnetic induction principle, zero magnetic flux comparator principle, Pockels electro optic effect and electric resistance partial pressure principle.Wherein simple, the stable work in work of the principle of resitstance voltage divider, accuracy are higher, thereby have obtained extensive use.China is backward relatively with the nationalization process of DC voltage transformer to DC transmission engineering, lacks corresponding development experience, mainly rests on Research on Principle and experimental stage, and the DC voltage transformer product that never is fit to engineering production in batches comes out.

This case is given birth to therefrom.

Summary of the invention

The purpose of the utility model invention is: to the characteristics of D.C. resistance voltage divider principle instrument transformer, and a kind of insulation system of appropriate design and radiator structure, and the development level of combination domestic industries; Through the choose reasonable insulating material; Traditional D.C. resistance voltage divider is transformed, effectively improved its radiating condition and insulating supporting structure, DC voltage transformer tradition is oil-filled, gas is improved to and adopts the become attached to dry insulation structure of medium of solid; Improved dielectric strength, and need not safeguard.The voltage transformer of conventional D.C. resistance voltage divider principle adopts liquid dielectrics such as oil, gas; Dielectric strength such as dry insulation medium; And need periodic monitoring internal component content; Safeguard constant, radiating condition is undesirable, and adopts the DC voltage transformer of heat-conducting type dry insulation structure to address the above problem well, makes it satisfy requirement of engineering in performances such as accuracy of measurement, insulation property, long-time running reliabilities.

The technical scheme of the utility model is: the dry type DC voltage transformer; Comprise that hollow combined insulator, bus line bank, shading ring, dry insulation medium, divider resistance string, equalizing capacitor, a hollow combined insulator constitute; It is characterized in that: the outer wall that the divider resistance string is wrapped in equalizing capacitor constitutes the capacitance-resistance measuring unit; Accomplish and divide compression functions, one time the bus line bank connects the divider resistance string, and the upper end of equalizing capacitor is provided with the hollow combined insulator that fits into of shading ring, equalizing capacitor and divider resistance; Equalizing capacitor plays even impulse overvoltage effect; Hollow combined insulator provides encapsulation and external insulation protection for the capacitance-resistance measuring unit, and the dry insulation medium is filled the space between capacitor resistor unit and the hollow combined insulator, for internal components provides support and insulating protection.The bottom low-pressure end of equalizing capacitor is isolated with insulation board, draws the second divided voltage holding wire.Can be according to the needs assembly unit more piece resistance and the capacitor unit of different electric pressures, the capacitance-resistance measuring unit fits into hollow combined insulator.

Equalizing capacitor is made up of more piece, and each joint equalizing capacitor all twines divider resistance, and then each joint equalizing capacitor is stacked, and the end face flange of every economize on electricity container is provided with connecting interface.

At first will shield resistance and measuring resistance and connect bunchiness as requested; Then with upper and lower two parts mounted in pairs of metallic shield shell in the draw-in groove of resistor ceramic shell; Draw the lead-in wire of shielding resistance string again from the Kong Weizhong of shield shell, couple together with regulation securing member upper and lower two parts at last shield shell.

The improvement of the utility model is: between hollow combined insulator (103) and divider resistance string (105), equalizing capacitance (104), fill the dielectric that can solidify; This dielectric has suitable material hardness, mechanical strength, insulation property, heat dispersion and operative weldability; Suitable material hardness guarantees that dielectric solidifies the inner components and parts of the unlikely destruction in back; Dielectric after suitable mechanical strength guarantees to solidify can support for internal components provides insulation; The suitable insulation performance guarantees the insulation property that dielectric is worked under high voltage; Suitable heat dispersion guarantees that the heat that dielectric can comparatively fast produce divider resistance outwards transmits, and processing performance guarantees its quality of engineering production in batches.The DC voltage transformer that adopts solid dielectric insulation to fill can solve traditional instrument transformer leakage of oil, gas leakage problem, and the testing agency of related physical quantity need be set, and is simple in structure, production and easy to maintenance.

The improvement of the utility model comprises: after single measuring resistance connects; Form resistance string, integral body is wrapped on equalizing capacitor (104) outer wall, and is fixing with the dielectric glue perfusion that can solidify again; Do not need the extra used insulation support that installs and fixes, effectively increase insulating reliability.

The improvement of the utility model comprises: the curable insulating material of filling has good performance of heat dissipation, and its normal temperature conductive coefficient is more than 0.7W/m.K.The resistance radome has bigger, slick and sly outline, can improve electric field.Its material is a copper, has good performance of heat dissipation, and the heat transferred that can rapidly resistance be produced is gone out.

The beneficial effect of the utility model is: the utility model has solved traditional D.C. resistance voltage divider principle instrument transformer in a series of problems such as components and parts are stable, heat dispersion is undesirable, insulating supporting structure complicacies; A kind of simple and practical DC voltage transformer version is proposed; Convenient for production; And need not safeguard to have higher dc voltage measurement accuracy and stability simultaneously, and make it possess the condition of batch process.

Description of drawings

Fig. 1 is the main TV structure sketch map of the utility model

Fig. 2 is the measuring resistance shielding and the location structure sketch map of the utility model

Fig. 3 is the vertical view of Fig. 2.

Among the figure: bus line bank of 101-; The 102-shading ring; The 103-hollow combined insulator; The 104-equalizing capacitor; 105-divider resistance string; 106-dry insulation medium; 107-DC voltage transformer base;

Among the figure: 201-measuring resistance string; The last shield shell of 202-; Shield shell under the 203-; 204-resistance connected node; 205-shields resistance string;

Below in conjunction with accompanying drawing and embodiment to the utility model further explain.

Embodiment

Below in conjunction with accompanying drawing the utility model is described further:

The utility model is applicable in the DC transmission system of each electric pressure such as 50kV, 500kV, 800kV; As shown in Figure 1, the divider resistance string is wrapped in the outer wall of equalizing capacitor, according to the DC voltage transformer of different electric pressures; The equalizing capacitor of configuration varying number; Each joint equalizing capacitor all twines divider resistance according to identical method, and then each joint is assembled together, and the end face flange design of every economize on electricity container has special connecting interface.

The installation of the utility model resistance string shown in Figure 2 and shielding construction thereof: at first will shield resistance and measuring resistance and connect bunchiness as requested; Then with upper and lower two parts mounted in pairs of metallic shield shell in the draw-in groove of resistor ceramic shell; Draw the lead-in wire of shielding resistance string again from the Kong Weizhong of shield shell, couple together with regulation securing member upper and lower two parts at last shield shell.

The divider resistance string that assembling is accomplished is wrapped in the capacitor outer wall, and fixes.

According to the needs assembly unit more piece resistance and the capacitor unit of different electric pressures, when capacitor resistor unit fitted into hollow combined insulator, low-pressure end application insulation board was isolated, to draw the second divided voltage holding wire.

The utility model should carry out dehumidification process after each components and parts is accomplished assembling, to get into the perfusion operation of dielectric.Adopt the priming by vacuum mode that the space between hollow combined insulator and the capacitor resistor unit is filled with the dielectric that can solidify, encapsulating should leave standstill the sufficiently long time so that dielectric glue fully solidifies after accomplishing, and reaches stable state.

Claims

1. dry type DC voltage transformer; Comprise hollow combined insulator, bus line bank, shading ring, dry insulation medium, divider resistance string, equalizing capacitor, hollow combined insulator; It is characterized in that: the outer wall that the divider resistance string is wrapped in equalizing capacitor constitutes the capacitance-resistance measuring unit; One time the bus line bank connects the divider resistance string; The upper end of equalizing capacitor is provided with shading ring, equalizing capacitor and divider resistance and fits into hollow combined insulator, and the dry insulation medium is filled the space between capacitance-resistance measuring unit and the hollow combined insulator.

2. by the described dry type DC voltage transformer of claim 1, it is characterized in that: the bottom low-pressure end of equalizing capacitor is isolated with insulation board, draws the second divided voltage holding wire.

3. by the described dry type DC voltage transformer of claim 1; It is characterized in that: equalizing capacitor is made up of more piece; Each joint equalizing capacitor all twines divider resistance, and then each joint equalizing capacitor is stacked, and the end face flange of every economize on electricity container is provided with connecting interface.

4. by the described dry type DC voltage transformer of claim 1; It is characterized in that: at first will shield resistance and measuring resistance and connect bunchiness as requested; Then with upper and lower two parts mounted in pairs of metallic shield shell in the draw-in groove of resistor ceramic shell; Draw the lead-in wire of shielding resistance string again from the Kong Weizhong of shield shell, couple together with securing member upper and lower two parts at last shield shell.