A novel and simpler way to include transient configurations in optimal coordination of directional overcurrent protections

•Transient configurations has been successfully included as linear constraints.•Consequently, approximate or non-linear methods are not longer necessary.•Inclusion of transient configurations has important influence on results.•Interrupting time of CB which causes the transient configuration has been included. This article shows an original and efficient way to consider transient configurations in optimal coordination of directional overcurrent protections. In the proposed method, the constraints related to transient configurations are directly included as simple linear constraints in problem formulation. This procedure is quite different than previous approaches, which need approximate or non-linear methods to solve the optimization problem. On the other hand, it is shown here that constraints related to transient configurations can have an important effect on results. Consequently, these constraints must be included in order to properly formulate the optimization problem. Furthermore, it is shown a method to properly include the interrupting time of circuit breaker which originates the transient configuration, in order to adequately formulate the optimization problem. In the analyzed examples, the effect of including this interrupting time was very low on optimal settings, and such an effect is more notorious in the optimal value of the objective function.