Optimal power flows with voltage stability constraint based on voltage stability indices and artificial neural networks

This paper describes the resolution of the optimal power flow (OPF) problem in the context of competitive electricity markets with a voltage stability constraint (VSC) based on the estimation of a voltage stability index (VSI) by means of an artificial neural network (ANN). The complexity of a VSI-based VSC consists in determining the VSI critical value. Thus, a methodology based on ANN for explicitly and algebraically determining such a critical value is proposed here. Numerical tests with 6-bus test-system are carried out in this study. This approach actually allows modeling the market clearing dispatch problem with power system security properly accounted in terms of voltage stability.