【作者】 段小帅；

【导师】 梁青；

【作者基本信息】 中国科学技术大学 ， 控制科学与工程， 2010， 硕士

【摘要】 振动控制是船舶领域内一个非常重要的问题。传统的被动隔振一旦安装完成,其参数难以改变,对隔振对象的状态变化和振源的变化没有较强的适应性,且被动隔振不能保证低频段的隔振性能。与其相比,主动隔振具有自适应性强、对低频振动控制效果好等优势,逐渐成为研究的热点。本文基于自行设计的第2版磁悬浮隔振器,开展了主动隔振相关的理论与实验研究。详细推导了隔振系统中振级落差、插入损失和力传递率三个隔振评价指标的表达式,得出了在一定的条件下三个指标相差一个常量的关系,提出了一种能全面准确反映主被动复合隔振效果的方法,然后介绍了第2版磁悬浮隔振器及弹性基座的设计情况,通过实验结果验证了评价指标之间的关系,并通过仿真研究了三个指标与系统的阻尼、刚度和质量之间的关系。磁悬浮隔振器中的作动器是电磁作动器,通过控制输入电磁铁的电流来控制电磁力的大小。为了进行有效的振动主动控制,需要建立电磁力与电流、气隙之间的关系。对电磁力实验建模方法进行改进,通过实验建立了电磁作动器动态电磁力与电流、气隙之间的关系,得到了比较准确的考虑频率因素的动态电磁力模型。给出了一种自寻优前馈控制方案,在磁悬浮隔振系统中获得了较好的实验效果。为了解决振动主动控制算法中次级通道建模的问题,在对滤波x最小均方(滤波x-LMS)算法几何分析的基础上,给出了一种不需要次级通道模型的自收敛前馈控制算法,在磁悬浮隔振实验平台上进行实验,在5.0Hz-15.0Hz频段内取得了良好的实验效果,最后研究了分块归一化对自适应前馈控制收敛速度的影响。更多还原

【Abstract】 Vibration control is a very important issue in the field of the ship. Because once the installation of the traditional passive vibration isolation is completed, it is difficult to change parameters. So it does not have strong adaptability for the changes of vibration objects and seismic focus. Furthermore, passive vibration isolation can not guarantee the performance of vibration isolation in low frequency. Compared with this, active vibration isolation is self-adaptive and has good control effect in low frequency. So it becomes a research hotspot gradually. This paper conducts the research on the theory and experiment related to active vibration isolation, based on self-designed version 2 of Electromagnetic Suspension Vibration Isolator (2nd ESVI).Three expressions of evaluation indices of vibration isolation (Vibration Level Difference, Insertion Loss and Force Transmissibility) are derived in detail. A constant difference between the three indices is obtained under certain conditions. An accurately and full method that reflects the combined effect of active and passive vibration isolation is proposed. Then the designs of 2nd ESVI and flexible base are introduced. The relationship between the evaluation indices is verified through the experimental results, and the relationship between the three indices and damping, stiffness, quality of the system is researched through simulations.The actuator in 2nd ESVI is an electromagnetic actuator. The electromagnetic force is controlled by controlling the input current of the electromagnet. In order to carry out effective active vibration control, the relationship between the electromagnetic force and current, gap is needed to establish. The experimental modeling method of electromagnetic force is improved. The relationship between the dynamic electromagnetic force and current, gap is established through experiments. The more accurate dynamic electromagnetic force model considering the frequency factor is obtained. A self-optimizing feed-forward control scheme is proposed and good experimental results are achieved in the electromagnetic suspension vibration isolation system.In order to resolve the problem of modeling the secondary path in the active vibration control algorithm, an self-converging feed-forward control algorithm without the secondary path model is presented based on the geometric analysis of filtered x Least Mean Square (filtered x-LMS) algorithm. Through the experiments on the electromagnetic suspension vibration isolation experimental platform, good experimental results are achieved in the 5.0 Hz - 15.0Hz band. Finally the impact on convergence speed of the block-normalized adaptive filtering algorithms is studied.更多还原