Partition-based bus renumbering effect on interior point-based OPF solution

The form of constraint coefficient matrix of an optimization problem significantly affects the solution procedure for finding the optimal results, especially when iterative algorithms are implemented. In power systems, the order of bus numbers affects the power system's graph adjacency matrix and accordingly affects the optimal power flow (OPF) problem's constraint coefficient matrix. Changing this constraint coefficient matrix might change the OPF solution time. In this paper, we show that the order of bus numbers affects the solution time of AC and DC OPF problems when an interior point method-based solver is used. We propose a partition-based bus renumbering algorithm to be implemented before solving the OPF problem. This algorithm constructs a well-patterned constraint coefficient matrix and speeds up the OPF solution procedure. Numerical results on the IEEE 118-bus system and the 13659-bus European transmission system show effectiveness of the proposed algorithm in reducing the OPF's solution time. Implementation of the proposed method leads to about 65% of timesaving when Matpower is used to solve OPF.