MAGNET SORTING ALGORITHMS FOR INSERTION DEVICES FOR THE ADVANCED LIGHT-SOURCE

Insertion devices for the Advanced Light Source (ALS) incorporate up t o 3000 magnet blocks each for pole energization. In order to minimize field errors, these magnets must be measured, sorted and assigned appr opriate locations and orientations in the magnetic structures. Sorting must address multiple objectives, including pole excitation and minim ization of integrated multipole fields from minor field components in the magnets. This is equivalent to a combinatorial minimization proble m with a large configuration space. Multi-stage sorting algorithms use ordering and pairing schemes in conjunction with other combinatorial methods to solve the minimization problem. This paper discusses object ive functions, solution algorithms and results of application to magne t block measurement data.