“Response Surface” Method in Magnetic Optimization

The use of "response surface" method in the sensitivity analysis and optimisation of electromagnetic devices is presented. The algorithm proposed is based on the first and second order polynomial least square fitting of the objective function of the optimisation. The choice between the first and second order model is made by looking at the local behaviour of the function. When needed, a complete second order model is built and an analysis of the approximating function is performed to put in evidence the possible presence of "valleys" that can be followed to get to the minimum. An outline of the strategy proposed and some results obtained both with analytically and numerically evaluated objective functions are presented and discussed.