基于时滞追踪的实时混合试验自适应补偿方法

实时子结构试验方法因其高效、适用面广，近20年来受到结构试验领域的重视。虽然近年来硬件技术有所提升，但仍受到一些限制，例如，作动器加载时运动机构和控制回路存在时滞，导致无法准确地施加位移。故实时子结构试验中，如何消除时滞影响成为试验成功与否的关键所在。为了减小和消除实时子结构试验中时滞的不利效应，该文首先根据液压伺服作动系统和Simulink建立了实时子结构试验平台，而后提出了基于时滞追踪的自适应补偿方法，最后采用数值仿真和子结构加载试验进行了验证和参数分析。结果表明:该算法可根据作动系统负载不同对时滞实时自适应地补偿，从而避免迭代试验。该方法不改变原控制器固有算法，也无需对系统时滞参量进行预判定或系统辨识，只需将提出的自适应补偿算法串联接入到系统之中即可，实用性、鲁棒性好。算法对非线性系统导致的时变时滞效应也有理想的补偿效果，通过一个铝合金梁的弯曲测试说明了该算法的正确性，可推广应用于结构实时仿真试验。

TIME-DELAY TRACING BASED ADAPTIVE COMPENSATION ALGORITHM FOR REAL-TIME HYBRID TESTING

The real-time hybrid testing method has drawn more attention in the field of structural test in the past 20 years due to its high efficiency and wide applicability.Although hardware technology has improved in recent years,it is still subjected to some restrictions.One of the most important factors is that the time delay of the control loop due to the actuator cannot apply real-time displacement on the specimen.Therefore,in the real-time hybrid testing,how to eliminate the influence of time delay becomes the key to the success of real-time hybrid test.To reduce the unfavorable effects of time delay,a real-time hybrid testing platform based on hydraulic servo drive system is established using Matlab/Simulink.Then,an adaptive compensation method based on time-delay tracking is proposed.Finally,numerical simulations are performed for parameter analysis and are validated by the specimen loading test.The results show that the algorithm is capable of adaptive compensation of time delays in different cases of loading patterns.Thus,it can avoid iteration during testing.This method does not need to change the original controller's inherent algorithm and does not need to perform parameter estimation or system identification for the time-delay system.It is only necessary to embed the proposed compensator into the system as a plugin component,which is efficient,practical,and robust.The algorithm also has a good compensation effect on the time-varying delay caused by the nonlinear system.The bending test of an aluminum alloy steel beam shows that the accuracy of the algorithm and can be widely applied to real-time structural simulation tests.