The Research On Characteristic Of Arc Discharge Of Intrinsically Safe Circuits And Non-explosion Detecting Method

The power criterion based on dynamic V-A characteristic and the experimentation of detecting the intrinsic safety characteristic are brought forward for the first time through the research on the mathematical model of electric arc current and voltage. By far, there are four kinds of mathematical model of arc discharge. The arc discharge characteristics based on current linear attenuation model and dynamic V-A characteristic model have been analyzed in this article. And the expression of arc discharge time, current reducing rate, arc resistance at the moment of discharge, arc energy and arc power are gained. The relationship between them and circuit parameters is discussed. The electric power criterion of intrinsic safe circuits based on dynamic V-A characteristic model is established through analyzing the relationship between the arc maximal power and discharge energy. The minimum of the maximal power is the critical value of electric power criterion. The power criterion is an important supplement to electric energy criterion. In order to eliminate the practical hidden trouble of intrinsic safe electric product by the greatest extent and make the manufacturers of intrinsic safe electric product detect their product before sending product to checkout station conveniently, a kind of non-explosion detecting intrinsic safety method is put forward through research in this article. The method use power critical value and the energy critical value of ignition as the criterion to judge the characteristic of intrinsically safe circuits. It has high use value when used in the field of producing and detecting the electric product of intrinsic safety practically.