A Practical Algorithm for Optimal Power Flow Based on Successive approximation Technique for Large-Scale Power systems

This paper presents a practical algorithm for solving large-scale optimal power flow problems. The proposed algorithm is based on a successive approximation technique in which an original power system can be divided into a main-system and several sub-systems. In the proposed algorithm, approximate voltage characteristics of sub-systems can be derived from the results of OPF for sub-systems, and the OPF for the main-system in conjunction with the derived approximate voltage characteristics of sub-systems can be solved. Finally, the optimal solution of the original power system can be obtained by successively coordinating the approximate voltage characteristics of sub-systems. Since the dimensions of problems to be treated in OPF are reduced, the proposed algorithm can effectively solve large-scale OFF problems. Moreover, the optimal voltage characteristics of sub-systems can be derived. The feasibility and effectiveness of the proposed algorithm are demonstrated on a typical power system model.