SU81280A1 - Test method for breaking capacity switches - Google Patents

Description

In installations for testing breakers with the ability to name two sources of electrical forces of different frequencies, both electromotive forces are applied to the test. We switch at the same time, which leads to a significant attenuation of the electromotive force of the two-frequency frequency by the arc extinction.

To increase the 1 st drawback, a wrench is proposed ;; т1. the source of the electrically moving force is the higher frequency at the end of the semi-diode, which does not suppress the arc in the switch under test.

FIG. Figure 1 shows an example of the schemes for performing the proposed method; in fig. 2 curves of the currents in the sections of the circuit.

In the circuit of FIG. 1 and. There are two combs; nuru - basic 1 1 circuit / and; ii) filling circuit //.

In these contours are included: invented test. 1, 1 /. auxiliary switch 2, which includes ycTpoiicTBo 3, ycTpoiicTBO 4 d, 1n real time shift / high frequency in time relative to current / 1 industrial frequency, reactors 5 and 6, source 7 and temporary emf low voltage of the primary coitur and guitars high voltage auxiliary 1h ;; ptug.

When a pulse is applied to the PA, the shut-off device closes: the main circuit / and the passage of the test current of the wiper frequency begins through the switch that is switched off.11 /. In this case, in the auxiliary circuit, // the current of the increased frequency will begin to pass through a predetermined time interval /, iqijir. 2). to; 1 yes will be filed - an impulse to the device 4 (mechanical n, - zlsktGPcheskoe), which will lock the circuit of the additional circuit.

Through the auxiliary switch 2 will pass raspnsn-t ;, the currents {g12-g -.- / 2) and at the moment of time ti when the current /.-.- is equal to i.po. .ch} ha in the auxiliary switch goes out (auxiliary switch; and test number 1 81280 „- 2 -

My switch-off opening opens after the device is closed and one test is formed on the test loop (). With che |) e :; the current zero, in the tested switch, the arc in it is extinguished, and the total voltage of the sources of voltage is restored at its contacts. Obviously, by varying the magnitude of the electrical shift / ,,. intersection of the current curves n and can be achieved; near their zero crossing and reduce to a minimum the fracture in the current curve passing through the circuit breaker under test.

The operation of the circuit shows that the current / jvioKeT has an arbitrary frequency, not necessarily an odd frequency and a multiple of the frequency of the current n. This allows us to avoid hard demands on the choice of additional circuit parameters, which turns out to be especially important: power.

It is very significant that the current of the increased frequency passes along the positive current loop for one semi-period, for at high voltages of the emf source. (a generator charged by a battery of capacitors) there are increased losses, and if the current b passes for five or seven and one period, then the op. p attenuates noticeably, which greatly reduces the equivalent of the thermal test power.

II: with d m with m and 3 about b P about te and and

The method of testing the breaking capacity of switches using two sources of electromotive forces of different frequencies, characterized in that the source of the electromotive force of the new frequency includes the HOMOHUI mechanical million electrical devices in the half-cycle, pre-blade in the tested switch.