Modeling, Design Optimization, and Verifications of Permanent Magnet Linear Actuators for Structural Vibration Mitigation Applications

Structural vibrations in modern buildings have been increasing concerns. If not properly controlled, they would give rise to serviceability problems and disturbances to occupants. The permanent magnet (PM) linear actuator-based active vibration mitigation strategy exhibits excellent dynamic performances on elimination of vibrations with complex modes, and has great potential. This paper describes modeling, design optimization, and numerical and experimental verifications of a PM linear actuator for structural vibration mitigation applications. Analytical expressions for prediction of the actuator performance are derived, and the linear actuator is then designed in optimization within a specific set of volumetric and thermal constraints in order to maximize the product of efficiency and power factor. It is shown that the proposed analytical model has provided a computationally efficient tool for design optimization, and the Halbach ratio and actuator width have significant impacts on the performance of the PM linear actuator. The results are validated by finite-element computations, and further verified by experimental measurements on a prototype actuator.