Method and installation for determining the air-gap dielectric characteristic in high-voltage switches.

摘要

The invention refers to a method and an installation for determining the air-gap dielectric characteristic used to evaluate the behaviour of high-voltage switches when subjected to excess switching voltages which arise during switching tests for low capacitance currents. The invention uses a control and adjustment panel (Pc) which issues the command for the opening of an auxiliary switch (I1) and the closing of the switch (I2) that is to be tested, which allows charging of a high-voltage capacitor (C2) via an autotransformer (AT), a mono-polar switch (i), a voltage step up transformer (T), a high voltage generator (Gc) and a protective resistor (RL). Then a closing command is sent to the auxiliary switch (I1) and an opening command is sent to the switch (I2) that is to be tested, so that the period of time between the closing of the auxiliary switch (I1) and the opening of the switch (I2) that is to be tested will not exceed 10 ms. The command for the cathode-ray oscillograph (OK) is given in a synchronised way so that the disruptive voltages, whose combined peaks give the air-gap characteristic, are registered at the same time with the break and make impulses of the switches.