结构参数对超磁致伸缩致动器动态特性的影响

本文从Terfenol—D棒的线性压磁方程出发，建立了超磁致伸缩致动器（GMA）轴向方向的传递函数动态仿真模型，研究了其主要结构参数，即Terfenol—D棒半径r和长度l、碟簧刚度kF、负载质量MF在对GMA阻尼系数ξ、固有频率f和动态性能指标上升时间tr、调节时间ts、超调量δ的影响。给出了具有优良动态性能的GMA应满足的两个条件，即阻尼系数ξ为0．707和系统固有频率f等于GMA交流驱动频率。最后，根据这两个条件对设计出的GMA进行了结构参数优化，当r=20mm，l=60mm，MF=0．57kg，kF=2000N／mm时，ξ=0．706，f=5680．7HZ，动态性能指标上升时间tr=0．943×10^-5s、调节时间ts=1．29×10^-4s，超调量δ=4％，明显改善了GMA的动态性能和稳态性能。

The impact of structural parameters on dynamic characteristics of giant magnetostrictive actuator

In this paper, the dynamic simulation model of transfer function of giant magnetostrictive actuators（GMA） is established along the axial direction on the base of the linear piezomagnetic equation of Terfenol-D. The impact of main structural parameters of Terfenol-D on dynamic characteristics of GMA are studied. These structural parameters, such as rod radius r and length l, plate spring stiffness kF, the load quality MF, have impact on damping coefficient ξ, natural frequency f and dynamic performance indexes including rise time tr, settling time ts and overshoot δ. In order to achieve the excellent dynamic performances, GMA must meet two conditions, namely the damping coefficient ξis 0.707 and natural frequencyfis equal to AC drive current frequency of GMA. Finally, the structural parameters of the GMA are optimized according to two conditions mentioned previously. When r=20mm,l=60mm,MF=0.57kg,kF=2000N/mm, dynamic performance indexes are enhanced to ξ=0.706,f=5680.7HZ , tr=0.943×10^-5s, ts=1.29×10^-4s, δ=4%. The dynamic performances and steady-state performances of GMA are improved significantly.