Applications of TRUST-TECH Methodology in Optimal Power Flow of Power Systems

The main objective of the optimal power flow (OPF) problem is to determine the optimal steady-state operation of an electric power system while sat- isfying engineering and economic constraints. With the structural deregulation of electric power systems, OPF is becoming a basic tool in the power market. In this paper, a two-stage solution algorithm developed for solving OPF problems has several distinguished features: it numerically detects the existence of feasible solutions and quickly locates them. The theoretical basis of stage I is that the set of stable equilibrium manifolds of the quotient gradient system (QGS) is a set of feasible components of the original OPF problem. The first stage of this algorithm is a fast, globally convergent method for obtaining feasible solutions to the OPF problem. Starting from the feasible initial point obtained by stage I, an interior point method (IPM) at stage II is used to solve the original OPF problem to quickly locate a local optimal solution. This two-stage solution algorithm can quickly obtain a feasible solution and robustly solve OPF problems. Numerical test systems include a 2,383-bus power system.