Design optimization of a micro superconducting magnetic energy storage system

The design of a superconducting magnetic energy storage (SMES) device requi res the determination of a current system that produces a magnetic field of a given magnetic energy and a low stray field outside the device. To optim ize the design, the amount of conductor and the device volume is minimized. High-temperature superconductor technology is utilized. Quench conditions must be fulfilled, In order to solve the multiobjective optimization proble m, two different methods have been used: the objective weighting method, wh ich combines the two objective functions (conductor volume and device volum e) into a new cost function by means of penalty coefficients, and one based on fuzzy logic. In both methods the (1 + 1) evolution strategy minimizatio n algorithm has been utilized. Moreover, in order to improve the solution o f the objective weighting method, the results given by the evolution strate gy algorithm are used as the starting point of a deterministic method (stan dard SQP method), The results are compared and discussed.