Comparison of optimization algorithms for the design of a brushless DC machine with travel-time minimization

This paper presents brushless DC (BLDC) machine design methods using the three Matlab´s optimization algorithms. Instead of optimizing the machine´s design with respect to a classic criterion, such as the minimization of losses, of weight or cost (usually, at one operating point), our criterion will be the time it takes for the machine to drive a variable load to fulfill its trajectory. This will require the calculation of the machine´s behavior on the whole of its operating diagram (torque/speed diagram). A simplified analytical model of a BLDC machine is used in order to compare the performance of the three algorithms. The characteristics of the optimization results and the use of different algorithms in cascade will be discussed.