The paper presents the application of IntervalMathematics as
a new method to, rigorously, address uncertainties associated
with capacitor installation in distribution feeders. While
several methods exist to determine optimal capacitor sizes and
locations in distribution feeders, these methods usually require
data which may be uncertain in nature. To account for such
uncertainties a heuristic method coupled with interval
mathematics is developed with the aim of maximizing the cost
saving by placing single node-located capacitors at a selected
sequence of nodes. The method determines a set of nodes to be
compensated with their associated interval capacitor sizes;
followed by a local search loop, at any one node, to determine
the final standard capacitor size at this node. While catering
for uncertainties, the method also offers utilities with
alternatives for selecting the standard capacitor sizes to be
used and the associated costs to be saved. This should enable
utilities to make informed decisions regarding installing
capacitors for reactive power compensation in their
distribution systems. A procedure is devised in order to
produce sharp bounds of the interval outcomes. Successful
implementation of the proposed method is described using a
nine buses example distribution feeder.