An online line switching methodology with look-ahead capability to alleviate power system overloads based on a three-stage strategy

An online line switching methodology to alleviate line overloads with look-ahead capability is proposed in this paper. This novel online methodology is based on a three-stage strategy, including screening, ranking, and detailed analysis and assessment stages for fast speed (online application) and accuracy. The proposed online methodology performs the tasks of rapidly identifying effective candidate lines, ranking the effective candidates, detailed analysis of the top ranked candidates, and supplying a set of effective line switching solutions for a current operating point. Both the current and the look-ahead post-switching power systems, after executing the proposed line switching action, meet the operational and engineering constraints. One distinguishing feature of the proposed methodology is that it provides a set of high-quality line switching solutions. The results provided by the exact AC power flow are used as a benchmark to compare the accuracy of the proposed three-stage methodology. The effectiveness and fast speed of the proposed line switching methodology with look-ahead capability are evaluated on the IEEE 39-bus and 2746-bus power systems with promising results.