Comparison of nonlinear programming techniques for the optimal design of transformers

In many papers on the application of nonlinear programming techniques to the solution of engineering problems, such as an induction-motor design, the sequential unconstrained minimisation technique is adopted. It is shown in the paper that a nonsequential approach will lead to the same end results with much less computational time. In addition it is shown that a considerable saving in computational time could be achieved in transformer design optimisation by considering the whole problem to consist of a single constraint such as the cost function, with the sum of all suitably weighted constraints on the design performances being brought under the objective function evaluation.