Calculating transmission line inductance using interval mathematics

Uncertainty is a major issue facing electric utilities in planning and decision making. Modeling uncertainty can be based on two general approaches. The first is a probabilistic approach where probability distributions for all of the uncertainties are assumed. The second approach is called "Unknown but Bounded" in which upper and lower limits on the uncertainties are assumed without probability distributions. Interval mathematics provides a tool for the practical implementation and extension of the unknown but bounded concept. The calculation of transmission line inductance is used as an example to illustrate the use of interval mathematics. Inductance values are calculated using the traditional single point numbers as well as interval numbers. The values from these two methods are compared to prove the validity of interval analysis.