中文摘要：

为提高射流伺服阀的动态性能,设计了采用桥式微位移放大机构的射流伺服阀用放大型超磁致伸缩执行器（AGMA）.建立了计输入位移损失的放大机构模型以及非线性位移输出理论模型,并采用有限元法对所建放大机构模型进行了对比验证,结果表明：放大机构的输入刚度模型最大误差＜0.78 N/μm,放大倍数模型最大误差＜0.22,放大倍数受输入位移影响较小.最后,试验研究了AGMA的静动态特性,结果显示：控制电流在-0.5A到0.5A缓慢变化时,AGMA输出位移约为78μm;当控制电流从-0.5A跃变到0.5A时,其峰值位移约为71μm,峰值时间约为0.014s,调节时间小于0.1s;当控制电流幅值为0.5A时,其输出位移幅频宽＞40 Hz,谐振频率约为30 Hz.

英文摘要：

In order to improve the dynamic performance of a jet-pipe electro-hydraulic servovalve,a novel bridge-type micro-displacement amplified giant magnetostrictive actuator （AGMA） for a jet-pipe electro-hydraulic servovalve is presented.The models considering the input displacement loss are deduced to describe the input stiffness and amplification ratio of the amplified mechanism.Then,the nonlinear dynamic model of AGMA is obtained.The above-mentioned models of the input stiffness and amplification ratio are verified by finite element analysis.The results show that the maximum error of input stiffness is less than 0.78 N/μm,the maximum error of amplification ratio is less than 0.22,and the effect of input displacement on amplification ratio is small.Finally,the experiment results show that the output displacement of AGMA is 78 μm at the control current slowly changing between-0.5 A and 0.5 A.However,when the control current steps from-0.5 A to 0.5 A,the peak displacement of AGMA is 71 μm with the peak time about 0.014 s and the settling time less than 0.1 s.The bandwidth is more than 40 Hz and resonant frequency is about 30 Hz at the control current＇s amplitude of 0.5 A.