A Study On Modern Interior Point Theory For Optimization Problems Of Power Systems

Optimal power flow is an analyzing and optimizing method of power networks, considering economy and security at the same time. It has been widely applied to secure operation, economic dispatch, energy management and pricing of electric power, etc. With the fast development of power market, the importance of practical uses of OPF is standing out increasingly.In nature, OPF belongs to a kind of large scale nonlinear programming problem with equality and inequality constraints, having a non-convex, high-dimension and highly sparse characteristic. And consequently, we should fall back on some optimizing algorithm with outstanding robustness and convergence. This thesis takes a study on the application of modern interior point algorithm, the most potential one at present, for OPF. The main contents of this thesis are as follows:1. Introduction to modern interior point theory and its applications to power systems;2. Establishing the formulation of conventional OPF problem, and applying a perturbed-KKT-conditions-based primal-dual interior point algorithm (P-KKT-PDIP) to solve it.3. Applying the P-KKT-PDIP algorithm to solve the optimal reactive power (ORP) problems of power system;4. Establishing the formulation of dynamic optimal power flow (DOPF) problems, and applying the P-KKT-PDIP algorithm to solve it;5. Establishing the formulation of total transfer capability (TTC) and available transfer capability (ATC) problem of interconnected systems, and applying the P-KKT-PDIP algorithm to solve it.6. Deduction of the decomposing model of spot pricing, and the way to attain the active and reactive spot pricing directly from the solution process of OPF.Vast numerical simulation tests and analysis of the proposed algorithm and the formulations have been applying to test or practical systems that range in size from 14 to 1047. It's demonstrated that, as a tool embodying combination of economy and security, OPF holds the balance in the optimal problems of power systems. At the end of the thesis, a discussion is given on the existing problems and the prospects for the OPF problems.