Solution of optimal power flow problems by semi-definite programming

A new method using semi-definite programming (SDP) to solve optimal power flow (OPF) problems was presented. Named as SDP-OPF, the proposed method involves reformulating the OPF problem into a SDP model, which is a convex problem, and developing an interior point method (IPM) for SDP. Furthermore, the SDP sparsity technique can greatly improve the efficiency of storage and computing. A simple 4-bus power system was employed to explain the implementation process, which includes converting the OPF problem to the SDP model and mapping the results of SDP's to the OPF solutions. Extensive numerical simulations show that the results by SDP-OPF are the same as by NLP-OPF. SDP-OPF has the super-linear convergence, and it can guarantee the global optimal solutions within the polynomial times. Therefore, the study for SDP-OPF offers a good prospect.