Optimal transmission switching based on auxiliary induce function

Optimal transmission switching (OTS) has become a research focus in recent years as a new operational method for power systems. OTS is modeled as a mixed-integer programming (MIP) problem and it is difficult to solve it within short time horizon. Current acceleration heuristics cannot guarantee both the computational accuracy and efficiency. In this paper, a new concept called auxiliary induce function (AIF) is proposed. Based on the result of the relaxation problem, the coefficients of integer variables are strategically decided in AIF. Then the AIF algorithm is proposed, which properly adds the AIF function into the objective function of the OTS model. AIF algorithm is able to speed up the solving process for OTS while achieving exactly the same optimal solution. Case study on the IEEE 118-bus system shows that the AIF algorithm can improve 5 times as much the computation speed while obtaining the same optimal solution. Another case study on the IEEE 662-bus system indicates that the AIF algorithm is also capable of further improving the computational efficiency of current acceleration heuristics.