Tri-stable permanent magnet actuator (TPMA) has been widely used in industry. In this study, a new TPMA integrating a permanent magnet actuator and two centralizing disc springs is proposed for valve application. By taking the linear coefficient of force/stroke characteristic, startup force, holding force and response time as the optimization objective, the TPMA was optimized based on an improved hierarchical genetic-particle swarm algorithm (HGP) and 3D Finite element analysis (FEA) under volume constrain. The optimization process was analyzed in detail to prove the effectiveness of multi-objective design. The performance of the prototype was verified experimentally. The results showed that a good linear force/stroke characteristic of prototype was obtained, and the linear coefficient of force/stroke characteristic was 0.97. The startup force was 409 N and holding force was 332 N, which increased by 32% and 54% after optimization, respectively. The dynamic response time of prototype from center stability to extreme stability was 5.8 ms. The TPMA can be applied extensively in the valve control.
INDEX TERMSTri-stable permanent magnet actuator, multi-objective optimization, finite element analysis, force characteristic.