Optimised design of electric actuators for more electric aircraft considering machining and assembly errors

Abstract To the challenges posed by the complex structure and low reliability of existing hydraulic actuators used for more electric aircraft landing gear, this paper proposes an optimised design method for an electric actuator based on the principles of tubular permanent magnet linear motor employing a Halbach array. For this electric actuator, a subdomain model considering the longitudinal end effect is established by setting virtual permanent magnet regions at both ends of the Halbach array. The effectiveness of the proposed method is verified through a comparison with the finite element method. Subsequently, a surrogate model is developed using the proposed subdomain model, and an uncertain optimisation model considering machining and assembly errors is developed based on the interval possibility and the interval order theory. Compared to its initial design, the optimised structure increased the average thrust by 13.4% and reduced the thrust ripple rate by 87.2%, significantly improving the overall performance of the electric actuator. Finally, prototype experiments are carried out to verify the effectiveness of the proposed subdomain method and optimised approach.