Optimal power flow solution using the penalty/modified barrier method

The solution of the optimal power flow problem through the penalty/modified barrier method is described in this paper. This approach features considerable advantages over interior point methods. In this method, the inequality constraints are transformed into equalities by the introduction of slack variables, which are handled by either the modified barrier function or the quadratic penalty function. Then, first order optimality conditions and Newton´s method are applied in the solution of the problem. In order to validate the proposed method, electrical power systems of 3, 14, 30, 118, 162 and 300 buses were used as case studies, and the obtained results proved the method´s efficiency.