Optimal allocation of FACTS devices in distribution systems

Distributed generation has spread in distribution systems. That provides a new aspect such that the conventional analytical or control methods do not necessarily work so well. As a result, it is important to reconsider voltage and reactive power control in distribution systems. In this paper, a method is presented for the optimal allocation of FACTS (flexible AC transmission systems) devices in distribution systems. This paper focuses on a case where wind power plants exist in distribution systems. The output of the wind power is influenced by the weather conditions. That causes the fluctuation of the nodal voltages in distribution systems. The conventional tools such as SVRs (static voltage regulators) do not necessarily work so well. Thus, the importance of voltage and reactive power control has been recognized in distribution automation. In this paper, SVCs are introduced to maintain the nodal voltage magnitudes. The problem formulation is how to place SVCs that allow compensation of reactive power for the generation change of the wind power. To solve it efficiently, this paper examines the use of the meta-heuristics that are involved in intelligent systems as a global optimization technique