Introducing prob-a-sag - a probabilistic method for voltage sag management

Abstract

Comprehensive voltage sag management in a power distribution system includes the technical and economic impact of sags, annual frequency of sags, as well as the effect of possible mitigative means. A probabilistic approach is required for performing the task in complicated industrial processes. Prob-a-sag is a novel method combining all these features. Two-dimensional arrays are used for expressing the quantities and carrying out the analysis or optimization. Equipment sag sensitivity is expressed as tripping probability, which enables the probabilistic sensitivity assessment of a large process. The method is very flexible; increasing the array resolution improves the result precision. If sag quantities other than depth and duration are preferred, we may increase the number of array dimensions accordingly. Prob-a-sag is compatible with any spreadsheet application, or may be implemented in sophisticated network analysis software.