Case Studies on the Application of the Exhaustive Optimization Method Based on Screening and Zoom Techniques

The present paper presents an exhaustive optimization method based on screening and zoom techniques and its application in two case studies involving electromagnetic devices. The method is based on the design of experiments technique, combining optimization algorithms with numeri-cal simulations. The solution of the optimization problem is performed in two stages: global modeling (coarse optimiza-tion) and actual optimization (fine optimization). In the first stage, a partitioning of the entire feasible domain is per-formed, especially in the areas where there are extrema of the objective function. Their location is signaled by the sign variations of the local effects of the design variables calculat-ed by a screening technique. In the second stage, the actual optimization takes place using the zoom technique, initiated around the point found in the first stage. The paper con-cludes with two case studies in which the application of the method on 2-D models of electromagnetic devices is exempli-fied. The optimization problems are to maximize the devel-oped forces while maintaining the overall dimensions and the cross-sections of the coils, depending on two geometric parameters. The method was applied up to zoom level 5, obtaining a considerable improvement in the performances of the electromagnetic devices. The great advantage of the exhaustive method is the determination of the global extre-mum of the objective function, which becomes all the more expensive the greater the number of design variables and the finer the partitioning.