Stochastical and statistical assessment of voltage dips

Short duration voltage dips due to short circuits are generally considered a serious power quality problem. To decide on the suitability of mitigation methods, knowledge is needed about the expected number of dips as a function of magnitude, duration and other characteristics. This knowledge can be obtained through the use of power quality monitors or by means of stochastic prediction methods. In this paper, two methods for the stochastic prediction of voltage dips are presented: the method of fault positions; and the method of critical distances. Both are applied to the same power system and the results are compared