SU502345A2 - Device for testing high-voltage switches - Google Patents

Description

This invention relates to the field of creating installations for testing circuit breakers using synthetic circuits and can be used in laboratories of discontinuous capacities and on network test benches that are equipped with oscillating circuits.

The basic author's certificate, AB 382029, describes a known device for testing high-voltage circuit breakers, in which to increase the power required for testing the main and auxiliary breaks of a switch, by reducing the voltage attenuation of a high-voltage oscillator capacitor bank in a specified circuit in series with resistance reproducing the shunt resistance of the tested switch or resistance, which determines its own voltage recovery rate Circuit, included additional resistance, which is shunted by an additional disconnecting element. To reduce the current in the additional disconnecting element, a second additional resistance is connected in series with this element, and in order to prevent the regenerating voltage from rising too quickly after the arc is extinguished, the additional disconnecting element must

inductance and additional capacitance in the high-voltage circuit an additional inductance is plugged, which is shunted by another additional ot | key switch.

However, in a known device, a steady-state reconstructive voltage is a slowly dying aperiodic voltage, while in real conditions it should be a continuous alternating regenerative voltage of industrial frequency. This leads to insufficient equivalence of the direct tests of the conditions of such tests, when re-ignitions of the arc in the tested switch during the occurrence of steady state voltage (return voltage) are possible on it.

The purpose of the invention is to obtain a variable continuous voltage and a reducing voltage of the transformer.

This is achieved by the fact that the device is equipped with a transformer, the primary winding

which is connected in parallel to the low voltage circuit, and the secondary winding

connected in parallel to the oscillatory

circuit high voltage circuit and shuntyrozan reactor. In addition, the device

equipped with a final reactor, connection. d..X) 6sh (Ц point of disconnecting element-eNtag N and test switch l on,, point reaction-Lair and secondary winding of traxformatrr.t i

In the drawing, pr6dsta: the scheme of the proposed device. An undervoltage circuit consists of an ev generator with an inductance of / g, disconnecting an OE element, and an IW switch being tested. In parallel, e and / ,. A branch from a: active resistance and discharge PI and the transformer primary winding G. are connected. The secondary winding of the transformer is shunted by the reactor L and connected to the junction point OE and IW through the reactor L. The disconnecting element OE is shunted by the high value of a high voltage, consisting of a RZ surge arrester, two Cj and C2 capacitor batteries of two peaiKTOpOB Z, 2 and Lo. The branch is shunted, in turn, by a branch of the sequence P and active CO-resistance 2 and R. After this, the reactor L2 is shunted by the disconnecting element OE, and the resistance R is shunted through the resistance R by the disconnecting element OE.

The device works in the same way as described in the main author's certificate No. 382029. When a non-yellow voltage circuit is closed, a current of industrial frequency passes through the OE and IW. With advance in relation to the passage of this current through zero, the P-voltage is triggered, and through the OE, besides the industrial frequency, the high-frequency current closes. In the area of am: the current amplitudes of the higher frequency, the PZ glitter is triggered. The current in the MA shuts off shortly before the zero crossing and the arc extinction in the IW. The current in the OE and OE is disconnected at a certain M time interval when carrying the arc arc in the circuit breaker under test. In this case, in the branch, a much smaller current is already flowing, since

/., + C /.,.

.k .k to

This circumstance makes it possible to de-cover the losses in the oscillatory circuit of a high-voltage circuit from the generator Vg through a step-up transformer T.

Consider the installation work if

L - O, i.e., there is only one reactor L. Then, after extinguishing the arcing in the PE, the transformer is loaded with a lagging current in L, and the current is not the current of the oscillating circuit (at the steady state frequency), and L is chosen so that the transformer G was loaded with a small lagging current equal to the difference of these currents. Then, in the generator circuit, a steady state can be reached for the power frequency if the power factor of the generator branch is determined by / J. and J) will be close to: power factor for a transformer G loaded with an oscillating circuit (taking into account resistance +) - This provides a continuous return voltage on the test switch IW.

If, besides reactor U, reactor L is also included, it is possible to substantially lower the voltage of the secondary winding of the transformer T, approximately in relation to Lj (L + + L), the parameters chosen are valuable, the outcome of a mode close to the conditional resonance of the currents in parallel branches L and С -L -L2-С- - -L. In this case, the tuning mode should also ensure that a lagging current is obtained in the primary winding of the transformer T. Then, also, the installed circuit voltage at the industrial frequency and the continuous return voltage on the test switch are provided.

Claims (2)

1. Device for testing high-volt switches according to aut. St. N ° 382029, due to the fact that, in order to obtain a non-temporarily continuous restoring voltage, it is equipped with a transformer, the primary winding of which is connected in parallel to the low-voltage circuit, and the secondary winding of the transformer is connected in parallel to the oscillating circuit high voltage circuits and shunted by the reactor. 2. The device of claim 1, characterized in that, in order to reduce the secondary transformer, it is equipped with an additional reactor connected between the common point of the disconnecting element and the switch being tested and the common point of the reactor and the secondary winding of the transformer. JVW l f-y-v., / I .U.,. t.