DE1903412A1 - Synthetic check circuit - Google Patents

Description

The invention relates to a synthetic test circuit for Testing the breaking capacity of high-voltage circuit breakers with a high-current circuit in which the DUT and an auxiliary switch are connected in series, and with a high voltage circuit, which is switched in parallel to the auxiliary switch after the last passage of the high current, whereby in parallel A capacitor is connected to the auxiliary switch. target The invention is to improve the performance of the test circuit in the event that switches with a low-resistance parallel resistor are to be tested. It is known that such low-resistance tarallelv / ide resistances serve in particular with compressed air switches to facilitate the arc extinguishing and to attenuate the voltage that returns after 'arc extinction, so that switching off is favored *'

In a test circuit of the type mentioned above, fiction according to a test object with a low-resistance parallel resistance, this was connected in parallel to the series connection of the test object and auxiliary container. In this way, when the test specimen is subjected to a realistic stress, the stress on the heat source is reduced, because it is no longer undesirably discharged by the parallel resistance.

For a more detailed explanation of the invention, reference will be made in the following the drawing describes an exemplary embodiment *

009832/091

BATH ORIGINAL

PLA 68/0189

In Fig. 1 is the circuit diagram of a synthetic test circuit drawn according to the invention. You can see the high current incr ice 1 with the high current source 2 and the inductance 3, with the the auxiliary switch 4 and the test switch 5 connected in series \ are. Parallel to the series connection of auxiliary switch 4 and test switch 5, a capacitor 6 is connected, which for a suitable steepness of the first part of the after the power interruption " recurring tension. ·

The high-voltage circuit 9 of the test circuit is parallel to the auxiliary switch 4 with the capacitor 10 as a high voltage source. In series with a spark gap 11 and a resistor 12 to limit the amount supplied by the high voltage source; Current is switched. Also parallel to auxiliary switch 4 is a capacitor 15, which has the repetitive voltage of the high "" ",. Circuit leads to the test switch -5.

The test switch 5 is a maximum voltage switch with a large switching capacity, which, during operation, has a low-resistance resistor 18 parallel to its switching path or part of its circuit path, as indicated by dashed lines in üUg.- 1 / The parallel resistor 18 ensures in a known manner for a ■■ ' ■ _ ■ Flattening of the recurring voltage at the switch, so that the switching capacity of the switch is improved . In the case of switches with several switching points connected in Heibe, the resistor 18 can also be used to control the voltage distribution across the individual switching sections.

In the test circuit according to the invention, the resistor 18 is not in the usual way parallel to the test object 5, but, as indicated at 18 ', parallel to the series circuit. "from test item 5 and auxiliary switch 4. You then get a

BATHROOM GINAL

■ TIA 68/0189 - 3 -

reduced load on the high voltage circuit 9 such as the following Representation of the mode of operation on the hand of the in Fig. 2 cal Recognize the indicated tension curve over time

If the switches 4 .and 5 interrupt the high current during a test, the high current circuit 1- initially supplies the first part, the γ / ied er coming voltage. This partial voltage is denoted by L% in FIG. As you can see, is the paral- {LeLv / esistance 18 'for. this voltage stress parallel to the test item 4, since the capacitor 15 represents a low resistance for the voltage. The cons, therefore, supports. 18 'in the arrangement shown was the switching capacity of the test object 4, as would be the case in operation in the arrangement shown in dashed lines. .
(18)

To increase the voltage stress on the test object 5, the high-voltage circuit 9 is then switched on by igniting the spark gap 11. Its voltage is labeled U ^ in Fig. 2. ^ It is added to the voltage Uj, so that the stress on the test object 5 as a whole is given by the voltage ¹ ' Vi ₇ = U-] + X $ 2. In contrast to The normal arrangement of the parallel resistor 18 shown in dashed lines, in which the full voltage U ₇ would be applied to the parallel resistor, but in the test circuit according to the invention the parallel resistor is only loaded with the voltage U-. In other words, the high-voltage source 10, which naturally does not so current strong as the high-current circuit, is less beanspruch £ in the inventive test ^circuit: .als' when the Parallelv / esistance in a conventional manner directly "parallel to the test specimen 5 would. Therefore, in the invention, the test specimen 5 can be used without inadmissible changes in the parameters essential for arc extinction

009632/099 «-4-

PM 68/0189.

Effect of the Paxalleli7iderstande, s-18 ^: 'with> iäer men 2JUBgsb € befiiQliU33g, than this would normally be the case with your parallel resistance 18.

2 figures "'- ■

1 claim. "'' .- ■■■ '

0 0 94-3.2, / :, 0: 9.9 9,

BAD S ^ BfNAL ^;

Claims (1)

PLA 68/0189 Synthetic test circuit for testing the disconnection ability of high-voltage circuit breakers with a high-current circuit in which the test object and an auxiliary switch are connected in series are, and with a high voltage circuit that goes after the last liull passage of the Iloch current connected in parallel to the auxiliary switch is, v / whether a capacitor is connected in parallel to the auxiliary switch, characterized in that with a test object (5) with a low-resistance parallel resistor (18) this parallel to the series connection of the test item (5) and auxiliary switch (4) is switched (18 '). 00 98 32/0999 AED L ee rs ei f e