Optimum power flow solution using a non-interior point method

Formulation of the optimum power flow problem using a smoothing based non-interior point method is described in this paper. Like the primal dual interior point method the proposed method makes use of the slack variables to handle the inequality constraints, dual variables to form the Lagrangian function and employs the KKT optimality condition and Newton's method to solve the resultant equations. The proposed method uses a smoothing function instead of logarithmic barrier to handle the complementary condition thereby overcomes the limitation of the variables to be in the interior of the feasible space through all iterations. Also, the smoothing parameter is treated as a variable of the original problem thus avoiding the necessity of heuristics in updating the value of the smoothing parameter, which approaches zero as the convergence is approached. (C) 2006 Elsevier Ltd. All rights reserved.