Analysis and design of a moving-magnet type linear actuator with repulsive magnetic forces

The paper describes a newly developed miniature moving-magnet type linear actuator with proportional action that uses repulsive magnetic forces. Out of four possible structures, two with mobile magnets and two with fixed ones, the most simple and cheap prototype was chosen, offering good possibilities to obtain a miniature structure. A comparative numerical analysis for two types of mobile element justifies the adopted constructive solution. A laboratory prototype was analyzed numerically and experimentally in view of a possible optimization, the experimental and numerical results being in good agreement. Finally a prototype actuator was built and tested.