Comparison of Different Approaches to Consider the Geometric Validity in the Metamodel-based Optimisation of Electrical Machines

Abstract:
In the electromagnetic optimisation of electric machines based on metamodels, the designs investigated are no longer built and calculated using finite element (FE) software, but instead only the metamodels are evaluated. The geometric validity can first be checked when validating the optima after the optimisation. In this process, an unconstrained, highdimensional design space leads to a large number of supposedly optimal but invalid designs, with the result that the optimisation fails. For this reason, three different approaches will be presented and compared in this paper: building and checking the validity of the designs during optimisation versus using a classifier to predict geometric validity versus evaluating analytical constraints as inequalities that guarantee geometric validity when satisfied.