CN201707395U

CN201707395U - Head-disassembling-free testing circuit of capacitance type voltage transformer

Info

Publication number: CN201707395U
Application number: CN2010202360795U
Authority: CN
Inventors: 刘勋; 曹海军; 李明
Original assignee: HUNAN ELECTRIC POWER COMPANY SHANGQIU POWER SUPPLY Co
Current assignee: HUNAN ELECTRIC POWER COMPANY SHANGQIU POWER SUPPLY Co
Priority date: 2010-06-24
Filing date: 2010-06-24
Publication date: 2011-01-12
Anticipated expiration: 2020-06-24

Abstract

The utility model discloses a head-disassembling-free testing circuit of a capacitance type voltage transformer, which comprises a C11 testing circuit and C12 and C2 testing circuits, wherein the C11 testing circuit comprises capacitors C11, C12 and C2, a reactor L and an intermediate transformer XT, one end of the capacitor C11 is grounded, the other end of the capacitor C11 is connected with the capacitors C12 and C2 in series, one end of the intermediate transformer XT is connected between the capacitors C12 and C2 by the reactor L, and the other end of the intermediate transformer XT and one end of the capacitor C2 are connected with a shielding end; and a high-voltage end is connected between the capacitors C11 and C12, and a measurement end is grounded. The testing circuit reduces the testing steps greatly and has simple operational procedures, accurate testing data and small reading errors.

Description

A kind of not disconnection hookup of capacitance type potential transformer

Technical field

The utility model relates to a kind of capacitance type potential transformer, is specifically related to a kind of not disconnection hookup of capacitance type potential transformer.

Background technology

Capacitance type potential transformer (being called for short CVT) is a kind of crucial high-tension power transmission and transformation equipment, and the voltage transformer (VT) that China 110kV and above electric system are used at present mainly contains capacitance type potential transformer and electromagnetic potential transformer.Because CVT has the dielectric strength height, can reduce thunderbolt shock head steepness, can not be with system generation ferroresonance, cost is low and can be used for advantages such as power line carrier communication by the double as coupling condenser, simultaneously again because associated materials and improvement of Manufacturing Technology, so from twentieth century since mid-term CVT use and to develop rapidly, the quantity of using in electric system in recent years is very huge, not only on transformer station's line outlet, use, and extensive application replaces electromagnetic potential transformer in bus and transformer outlet.CVT generally is applicable to 110kV and above electric pressure, but owing to be subjected to design level, manufacturing experience, the restriction of multiple factor such as technological level and starting material, break down in the back if put into operation, will influence electric power netting safe running, be subjected to the influence of running environment and electric pressure, the equipment of 220kV and above electric pressure particularly, stature is tall and big, it is heavy to go between, make that the workload of tearing an electrical test open is big, the difficulty height, power off time is longer, and it is all charged to add surrounding devices, work by force and understand serious threat equipment and personal security, this tests CVT before use with regard to needs.Existing hookup to the capacitance type potential transformer not disconnection, when experiment power supply harmonic interference or external electrical field disturb when strong, electric bridge is difficult to balance, reading error is bigger, make testing procedure various and eliminate the measure of disturbing, the program complexity, the human factor influence is big, therefore, the hookup that how to find a kind of new not needing at the trial capacitance type potential transformer to be torn open head is the task of top priority.

The utility model content

By Given this, the purpose of this utility model provides a kind of not disconnection hookup of capacitance type potential transformer, can effectively solve the problem that occurs in the prior art, the utility model is realized test of capacitance type potential transformer dielectric loss and electric capacity test in conjunction with self-excitation method and high-tension shielding method.

To achieve these goals, the utility model is by the following technical solutions:

A kind of not disconnection hookup of capacitance type potential transformer, comprise C11 hookup and C12, C2 hookup, wherein, described C11 hookup comprises capacitor C 11, C12, C2, reactor L and intermediate transformer XT, capacitor C 11 1 end ground connection, the other end is connected with capacitor C 12, C2, and intermediate transformer XT one end is connected between capacitor C 12, C2 through reactor L, and the intermediate transformer XT other end is connected the shielding end with capacitor C 2 one ends; Capacitor C 11, the indirect high-pressure side of C12, measuring junction ground connection;

Described C12, C2 hookup comprise capacitor C 11, C12, C2, reactor L and intermediate transformer XT, capacitor C 11 1 end ground connection, the other end is connected with capacitor C 12, C2, intermediate transformer XT one end is connected between capacitor C 12, C2 through reactor L, connect measuring junction between capacitor C 11, C12, intermediate transformer XT other end ground connection, another termination high-pressure side of capacitor C 2.

The beneficial effects of the utility model are:

The utility model when test C11 electric capacity and dielectric loss, is used the reversal connection line measurement in conjunction with self-excitation method and high-tension shielding method, and δ point and intermediate transformer tail end X point are connect the shielding end that electric bridge goes between, and eliminates the influence of branch road capacitance current; When test C12 and C2, use be that self-excitation method is measured.Hookup of the present utility model has significantly reduced test procedure, and running program is simple, and test figure is accurate, and reading error is little.

Other advantages of the present utility model, target and feature will be set forth to a certain extent in the following description, and to a certain extent, based on being conspicuous to those skilled in the art, perhaps can from practice of the present utility model, obtain instruction to investigating hereinafter.Target of the present utility model and other advantages can realize and obtain by specifically noted structure in following instructions or the accompanying drawing.

Description of drawings

Fig. 1 is the wiring diagram of the utility model C11 hookup;

Fig. 2 is the wiring diagram of the utility model C12, C2 hookup.

Embodiment

As shown in Figure 1, the C11 hookup comprises C11, C12, C2, reactor L and intermediate transformer XT, C11 one end ground connection, the other end is connected with C12, C2, intermediate transformer XT one end is connected to B point between C12, C2 through reactor L, and intermediate transformer XT other end X point is connected with the shielding end through the δ point; The A point connects high pressure between C11, C12, measuring junction ground connection.In test C11 process, to measure with reversal connection collimation method (pressurization of A point, C11 upper end line-to-ground), measuring voltage is 2kV.In the normal course of operation, δ point and intermediate transformer XT tail end X point ground connection, if δ point and X point are not taken apart, then loss and the electric capacity of C2 and intermediate transformer XT primary winding Ca are all entered in the loop, the electric capacity of measuring is connect with C12 after C2 and the Ca parallel connection electric capacity and loss with gained after C11 is in parallel again.Therefore want to record loss and the electric capacity of real C11, just must connect the shielding of electric bridge lead-in wire to δ point and intermediate transformer XT tail end X point and hold, make that the capacitor cell below the A point does not enter the measurement loop among Fig. 1, thus the influence of elimination branch road capacitance current.

As shown in Figure 2, C12, C2 hookup comprise C11, C12, C2, reactor L and intermediate transformer XT, C11 one end ground connection, the other end is connected with C12, C2, intermediate transformer XT one end is connected to B point between C12, C2 through reactor L, the A point connects measuring junction, intermediate transformer XT other end ground connection, and the other end δ point of C2 connects high pressure.When test C12 and C2, use be that self-excitation method is measured, exerted pressure by intermediate transformer XT Secondary Winding ax this moment, through intermediate transformer XT transformation, C11 upper end line-to-ground, electric current entered the earth after staying C11, do not measure the loop and do not enter, do not influence the test effect.Through practice, should note in the wiring process: hi-line is answered unsettled face intangibly, otherwise its additional over the ground dielectric loss can cause error, and available Thin cable connects high-tension terminal and CVT test product and also slings.Because the C2 electric capacity is big, add the output capacity restriction of intermediate transformer XT, frequency conversion dielectric loss instrument, CVT and resonance occurs when avoiding testing that frequency of operation should be got 40～47.5Hz, and B point voltage UB ≯ 2.5kV.

Claims

1. the not disconnection hookup of a capacitance type potential transformer, comprise C11 hookup and C12, C2 hookup, it is characterized in that: described C11 hookup comprises capacitor C 11, C12, C2, reactor L and intermediate transformer XT, capacitor C 11 1 end ground connection, the other end is connected with capacitor C 12, C2, intermediate transformer XT one end is connected between capacitor C 12, C2 through reactor L, and the intermediate transformer XT other end is connected the shielding end with capacitor C 2 one ends; Capacitor C 11, the indirect high-pressure side of C12, measuring junction ground connection;