Switch and tie lines allocation in distribution systems using NSGA II

An optimization mathematical model to minimize the costs associated with energy not supplied and investments on the allocation of sectionalizing switches and tie lines between branches and / or feeders in primary distribution systems is presented. This is a mixed integer nonlinear programming model, which considers the power flow constraints and continuity indexes. A set of trade-off solutions between total cost of investments and network reliability is obtained using a multi-objective genetic algorithm (Non-Dominated Sorting Genetic Algorithm II - NSGA II. It is demonstrated that by considering these two elements at the same time, the results are better than when these elements are considered isolated on the mathematical models.