Speed-based multiobjective optimisation of a cage-secondary permanent magnet linear eddy current brake

This paper proposes a multiobjective optimisation scheme for a new cage-secondary permanent magnet linear eddy current brake, where the secondary is designed to own the cage configuration with variable parameters. This unique structure is suitable for applying to the high-speed rail transit braking system. Via speed-based multiobjective optimisation for this eddy current brake, the objectives of short braking distance, light weight, and low manufacturing cost can be achieved. First, the detailed structure and principle are described. Second, the braking force performance is accurately predicted by the proposed 3D analytical method. And the influence of secondary materials and secondary parameter values on braking force performance in all speed ranges is analysed. Third, the sensitivity of the optimisation design variables is analysed by the gene distribution maps. Then, the genetic algorithm based on the analytical model is used for multiobjective optimisation in all speed ranges and the best design scheme is selected. Finally, the accuracy of optimisation and the analytical model is verified by prototype experiment and simulation.