UA143605U - DEVICE FOR TESTING ELECTRIC POWER SUPPLY PULSE EQUIPMENT - Google Patents

Abstract

The device for testing electrical equipment with overvoltage pulses consists of a pulse transformer, a magnetic circuit with primary and secondary windings and capacitor banks. The magnetic circuit of the pulse transformer is made of two separate cores, on which the primary windings and the common for both cores secondary winding are located.

Description

The useful model belongs to electrical engineering and can be used when testing electric power equipment for resistance to high-voltage lightning impulses and switching overvoltages.

A device for testing electrical power equipment with high-voltage overvoltage pulses (1) is known, which consists of a high-voltage transformer and high-voltage capacitors. The capacitors are charged in parallel, and discharged in series, creating a test pulse of high voltage of the required form on the object.

However, the disadvantage of this device is that it is constantly under the influence of high voltage. The creation of such a device is associated with significant economic losses, and its operation with harmful working conditions caused by air ionization processes and unforeseen breakdowns of external and internal insulation.

The closest in terms of technical essence and the largest number of essential features to the proposed useful model, which is taken as the closest analogue, is a device for testing electrical power equipment with high voltage overvoltage pulses (2), which consists of a pulse transformer with one core with primary and secondary windings and from capacitor banks.

The disadvantage of the closest analogue is the need to simultaneously adjust the parameters of the edge and fall of the test pulse at constant parameters of the capacitor bank and the primary winding of the transformer. The use of biasing will also allow adjusting only one parameter of the test pulse, that is the edge or the fall. The above described reduces the quality of the device for testing electrical power equipment with overvoltage pulses.

The task of the useful model is to create a device for testing electrical power equipment with overvoltage pulses.

The task is solved by the fact that in the device for testing electric power equipment with overvoltage pulses, which consists of a pulse transformer with a magnet wire with primary and secondary windings and capacitor banks, according to a useful model, the magnet wire of the pulse transformer is made of two separate cores, on which the primary windings are located and common to both hearts

From the secondary winding.

This will make it possible to improve the quality of the device for testing electrical power equipment with overvoltage pulses due to the formation of a pulse front on one cell, and a pulse decay on the second cell.

The above will allow us to draw a conclusion regarding the compliance of the proposed useful model with the "novelty" criterion.

A useful model is proposed, in which the magnetowire of the pulse transformer is made of two separate cores, on which the primary windings and the secondary winding common to both cores are located. This implementation of the device for testing electric power equipment with overvoltage pulses will allow forming the front of the pulse on one cell, and the decay of the pulse on the second cell.

The amplitude of the test pulse consists of the sum of the voltages on each cell, which is determined as,

Ovypr - 95 0". YuOvypr. . no no . not where: - the amplitude of the test voltage on the common secondary winding placed on two cores, V; what ; b2. the amplitude of the front and the decline of the test pulse from each of the two cores, B; y - Winter AVO Ktvi |y, Za Ma АВ2) Ktro 15ЖХ-352Ш2Т ;ИМЙЩШБШБ325Й2Й26ШШВЮУМЖШЮТЭТТ NN h t2 "ЗОЗ ; 2. where: 71, - cross-section of transformer cores, me;

AV. ; AV. change in induction on a partial cycle of remagnetization of the cores, Hn;

Who! Ktra is the voltage transformation coefficient on each cell;

Which - Min. Ktrg - Meter.

MIND. Mo

MMvypr number of turns on the common secondary winding placed on two cores, B;

Mt. oh - the number of turns in the primary winding;

Me. the number of turns in the secondary winding th. the duration of the pulse of the front and the decline of the test pulse, s;

The test pulse parameters are adjusted by changing the winding parameters of each cell. Submagnetization of the medium allows changing the magnetic permeability of the material of the medium, and accordingly, the inductance of the windings. A change in the inductance of the winding causes a change in the parameters of the voltage pulse on the windings included in the discharge circuit of each capacitor bank. The reliability and safety of the device is ensured by the fact that the process of forming a high-voltage pulse occurs on the low-voltage winding of the transformer, and high voltage is applied to the equipment only at the moment of the pulse.

Thus, everything described above distinguishes the device for testing electric power equipment with overvoltage pulses from known technical solutions and shows that the proposed technical solution has significant features.

The device for testing electric power equipment with overvoltage pulses is explained by drawings.

Figure 1 shows a device for testing electrical power equipment with overvoltage pulses, which consists of two cores 1 and 2, made of electrical steel. Primary winding 3 is placed on core 1, primary winding 4 is placed on core 2.

The common winding 5 is placed between the two cores 1 and 2. The arrester 6 is connected in series with the primary winding 3, and the arrester 7 is connected in series with the primary winding 4. The starting device 8 is connected on one side to the arrester b, and on the other side it is connected to the discharger 7. The capacitor battery 9 is connected in series with the discharger 6 and the capacitor battery 10 is connected in series with the discharger 7. The charging unit 11 is connected at one end to the capacitor 9, and at the other end it is connected to the capacitor 10 The magnetizing block 12 is connected to the windings 13, 14, which are magnetized.

In Fig. 2 shows the required form of the lightning overvoltage test pulse and the pulse duration parameters are given.

You. pulse duration, μs;

That. - duration of the front, μs; 0. pulse amplitude, V;

She time, μs;

In Fig. 3 shows the change in the magnetic permeability of the core material and the inductance of the windings.

The device for testing electric power equipment with overvoltage pulses is carried out as follows. Using the charger 11, the capacitor batteries 9 and 10 are charged to the specified voltage. When starting pulses from the unit of starting pulses 8 are applied to the dischargers 6 and 7, the capacitor batteries 9 and 10 are discharged to an individual magnetic medium, which are connected to the common high-voltage winding 5. To obtain a steep front of the test pulse, the discharge circuit of the capacitor battery 9 must have a small inductance , which is defined as:

I - PA «ZM where: Y. - magnetic inductance of the primary winding, Hn;

KA - magnetic permeability of magnetic material on a single partial cycle Hn/m; nal - AB/ AN where H is the magnetic field strength, A/m

Sh -th no -4l10 magnetic constant, Hn/m: . average magnetic line of the center, m;

Z. heart section, me;

M is the number of turns on the primary winding.

For this, the core using the magnetization unit 12 is transferred to a saturated mode, when the coercive force is maximum. The second capacitor bank 10 forms the duration and amplitude of the pulse decay, discharges to its core with minimal undermagnetization, operating on a partial cycle of magnetization with greater magnetic permeability Kg, and the winding

4 has a larger inductance and creates an aperiodic pulse of the required duration in the discharge circuit of the capacitor battery 10. On the winding 5 common to both cores 1 and 2, a test pulse with the necessary values of the front and duration is formed.

The use of a device for testing electrical power equipment with overvoltage pulses will improve the quality of its work by creating the necessary front and fall parameters of the test pulse on low-voltage windings of transformers and adjusting the parameters of the front and fall of the pulse separately by magnetizing windings on each unit.

Sources of information: 1. M.A. Babikov, N.S. Komarov, A.S. Sergeev. Technique of high tension. - Gosznergoizdat: - L. - M., 1963. 2. GOST 1516.2-97 Electrical equipment and electrical installations of alternating current for a voltage of 3 kV and higher. The general method of testing the electrical strength of insulation is the closest analogue.

Claims (1)

USEFUL MODEL FORMULA A device for testing electric power equipment with overvoltage pulses, consisting of a pulse transformer, a magnetic line with primary and secondary windings and capacitor banks, which is characterized by the fact that the magnetic line of the pulse transformer is made of two separate cores on which the primary windings are located and a common for secondary winding of both cores. J. o: a ie and --- SHO SHO K ho she More pt, spirit K o h - I Cho. eat M. ih i-e o HM y p-ch i ki u che i rak - shiv . i an ka She ; skl and t tsh ; ! , | with She and, and and about. ! i Ya t E tya Y hi ;. i ts is 5 / i y x 7 Z : ssh Y ke x Kt vche A KI i also: | ry we: x zozanni: Z Z Z "Sche sh sh sh: NO E 7 pakyuKeh I yati i! I g; her ZhK Sh BE: sho i i go: ZY | NOT / и KO чи кИ и / / ; Kn iz! / / child /- she i i I That i i N i i i skkkkhisoyuyuyusyusoniYa; / and El N : / her; Xia, S Zach eat and Sho y / 7 / -- y N no; Fig. 1