Modeling and Numerical Analysis of Stochastic Optimal Transmission Switching with DCOPF and ACOPF

Optimal transmission switching is proposed in recent years to optimize the power system operational cost. However, grid uncertainties are not included in the previous deterministic studies. With the rapid growth of renewable generations, the uncertainties in the grid have greatly increased, which cannot be ignored when making decisions in power system operations. This paper presents two mathematical formulations for stochastic optimal transmission switching with the direct current optimal power flow (DCOPF) and the alternating current optimal power flow (ACOPF). The two stochastic formulations are analyzed and compared with the previous deterministic formulation. The ACOPF based stochastic optimal transmission switching is solved directly, while the DCOPF based stochastic optimal transmission switching is solved by the L-shaped algorithm based on the Benders decomposition. A comparative numerical study is conducted on the modified IEEE-118 bus system. In most cases, the ACOPF based stochastic optimal transmission switching achieves the lowest expected operational cost among the three methods and is faster than the DCOPF based stochastic method.