Specifics of automatic switches commutation testing

Abstract

We demonstrate that the most efficient way to extinguish the short-circuit arc is extinguishing inside the camera with an arc extinguishing grid, which splits it into several smaller arcs. The active resistivity of these partial arcs decreases the amplitude of the current of the short-circuit arc, decreases the angle φ between current and voltage, which decreases the amplitude of the return current and enhances the condition for the arc extinguishing. We analyze the process of arc extinguishing in the three-phase circuit. We would like to note that during the extinguishing of the arc in the first extinguishing pole resistance of electric arcs in two other poles deforms the voltage triangle decreasing the coefficients of the scheme from 1.5 to 1.3 according to the experimental data. This allows to decrease the difficulty of the tests for maximum commutation capability. Simultaneously, we consider the necessity of the selection and regulation of the wave parameters (amplitude coefficient and normal mode) of the test circuit according to the standard for test preparation. Taking into account the decrease of the coefficient of the scheme and the real wave parameters will allow to objectively estimate commutation capability and to optimize the parameters pf the contact arc extinguishing system of an automated switch.