Primary and Secondary Congestion Management in Restructured Power Systems

In this paper a new strategy for congestion management is presented. Generally، in congestion management programs all considered contingencies are deterministic or stochastic. Therefore، congestion management cost is increased. In the proposed algorithm، congestion management program is divided to two parts، Primary and Secondary Congestion Management. Also، contingencies are divided in two groups. In the first group، the contingencies that should be managed by preventive actions are considered and the others are taken into account in the second group. The first group of contingencies is in primary congestion management. The secondary congestion management program starts from the nearest time to market run time. So، the secondary congestion management uses corrective actions for managing secondary group contingencies. Also، the secondary congestion management is capable of covering most uncertainties، especially load variations. The proposed method reduces congestion management cost.