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Title: Improving the Computational Efficiency of Optimal Transmission Switching Problems
Transmission switching is widely used in the electric power industry for both preventive and corrective purposes. Optimal transmission switching (OTS) problems are usually formulated based on optimal power flow (OPF) problems. OTS problems are originally nonlinear optimization problems with binary integer variables indicating whether a transmission line is in or out of service, however, they can be linearized into mixed-integer linear programs (MILP) through the big-M method. In such big-M-based MILP problems, the value of M can significantly affect their computational efficiency. This paper proposes a method to find the optimal big-M values for OTS problems and studies the impact of big-M values on the computational efficiency of OTS problems. The model was implemented on a modified RTS-96 test system, and the results show that the proposed model can effectively reduce the computational time by finding an optimal big-M value which ensures optimal switching solutions while maintaining numerical stability.  more » « less
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The 54th North American Power Symposium (NAPS)
Medium: X
Sponsoring Org:
National Science Foundation
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