Temperature stability of components for over-voltage protection of low-voltage systems

Summary form only given. The aim of this paper is to find over-voltage component which have the best temperature stability characteristics. We examined the influence on temperature variation of characteristics on following over-voltage components: 1) transient suppresser diodes (TSD), 2) metal-oxide varistors, 3) gas filled surge arresters (GFSA) and 4) polycarbon capacitors. According to experimental results we can conclude that TSD have reliable characteristics from 50 C to +90 C. For temperature over 90 C the use of TSD as over-voltage protection elements are not suggested, because their characteristics were significantly degraded. On the other hand, metal-oxide varistors have much better protective characteristics. At the room temperature (25 C) variation of breakdown voltage is about 3%. With the increasing temperature, varistors´ protective characteristics were improved. Also, it was found that a temperature variation from 90 C to +210 C changes the DC breakdown voltage of a GFSA less than 5% of the rated value. The temperature effect on the pulse breakdown voltage random variable was not determined. Polycarbon capacitors are relatively sensitive to temperature variation. We found two segments of increasing value of TGD with temperature (at low and at high temperature). Generally, with temperature increase the protective characteristics of polycarbon capacitors are degraded. Therefore by investigating the obtained results it can be noticed that metal-oxide varistors shows improvement of protective characteristics at high temperature. Also, we can conclude that GFSA shows the best stability characteristics over a wide temperature range. All obtained results are explained theoretically.