磁致伸缩作动器非线性敏感参数辨识及其稳定性主动控制

Magnetostrictive Actuator has been paid the wide attention and research in the vibration active control field because it is characterized by high frequency response, large output force and high energy density. However, the typical non-linear factors of Magnetostrictive Actuator, existed in its principle, may result in the serious nonlinear instability hidden trouble, which severely restricts its application and promotion in a lot of important equipments and applications. Addressing Magnetostrictive Actuator with its relative vibration active control system, and using nonlinear dynamics theory, this plan builds the nonlinear dynamic model to contain non-linear pre-compressive spring stiffness, dry friction, hysteresis lag and other nonlinear factors. Through theoretical analysis, simulation and principle experiment, this study reveals its nonlinear behavior rule, determines the sensitive parameters and instability boundaries, and searches the mechanism to escape the nonlinear instable area. Then, an optimized design method taking nonlinear stability margin as target is put forward, and a selection method and design criteria to get optimal parameters is provided. Furthermore, the general rule of the vibration active control strategy which takes the nonlinear stability as boundary conditions is studied, the control method of nonlinear stability is proposed, and by means of experiments reproduce and verifies the typical nonlinear dynamic behavior of Magnetostrictive Actuator. The main results will provide a theoretical basis and technical support for design Magnetostrictive Actuator and its safe and reliable operation, and will also provides a reference for other similar design of actuator.

磁致伸缩作动器因其具有频响快、出力大、能量密度高等独特优点，已在振动主动控制，换能等方面受到了广泛关注和研究。但由于本征非线性因素的存在，导致磁致伸缩作动器的应用存在重大非线性失稳隐患，严重制约了其在重要设备上的使用和推广。本项目以磁致伸缩作动器为研究对象，采用非线性理论建立包含非线性预压弹簧刚度、干摩擦及磁滞等因素在内的非线性动力学模型。通过理论分析、仿真和实验、揭示其非线性动力学行为规律，确定其非线性敏感参数及失稳边界，并研究跳出敏感区域方法。提出以非线性稳定裕度为目标的优化设计方法，给出最佳参数确定方法和设计准则。分析研究以非线性稳定为边界条件的振动主动控制策略的一般规律，给出非线性稳定的控制方法。并通过实验对磁致伸缩作动器典型非线性动力学行为进行复现和验证。主要研究成果将为磁致伸缩作动器的设计及安全可靠运行提供理论依据和技术支撑，对其它类型非线性作动器及振动主动控制具有借鉴意义。

针对磁致伸缩作动器（Giant magnetostrictive actuator，GMA）非线性因素多、模型建立及参数辨识困难、动力学行为复杂、不宜获得高精度控制且容易失稳等一系列技术难题展开了相关理论和实验研究。在分析GMA工作机理的基础上，结合磁滞模型理论、安培环路定理、力-磁-热耦合模型和GMA结构动力学方程，首次提出了一种包括非线性磁场、非线性刚度、非线性摩擦在内的全因素耦合非线性动力学模型。采用非线性动力学理论和方法，揭示了GMA系统存在的丰富非线性动力学行为，得出了GMA基于稳定性的结构参数设计准则。在研究GMA非线性控制策略的基础上结合稳定性的要求，提出了一种基于Lyapunov稳定性的逆模型前馈补偿模糊PD控制策略和基于模拟退火差分进化算法的模型参数快速辨识方法，给出了非线性失稳转捩机制，提高了GMA的动态跟踪精度和鲁棒性。基于非线性敏感因素研究的功能需求搭建了一个集性能测试评价、非线性敏感因素分析和控制策略研究于一体的多功能实验设备，并对GMA开展动静态性能测试、敏感参数测试及失稳特性提取和控制策略验证等实验研究。本课题取得的一系列创新成果进一步完善和发展了GMA的模型理论，并创造性的在结构设计和控制策略上引入非线性动力学理论及方法，有效的解决了GMA存在的非线性失稳隐患和高精度动态控制难题，为GMA的设计及安全可靠运行提供理论依据和技术支撑，并为最终推进其走向广泛应用奠定重要基础。