多源复杂激励下磁悬浮隔振系统机电耦合动力学模型及控制机理研究

It has the extremely vital significance to the national defense security to improve the performance of the submarines acoustic stealthy.With the development of the submarine, the structure of the mechanical equipments and the exciting mode has become more and more complicated. Due to the limits of space and weight in submarine, a lot of equipments either rigidly or flexibly were installed together to consist a multiple complex excitations isolation object .The active vibration isolation technology can overcome the defects of passive vibration isolation technology that the poor vibration isolation performance in low and resonant frequencies. Compared with other active vibration isolation technologies, magnetic suspension isolation technology has shown useful characteristics, such as wide response frequency range, fast response, high reliability,and the electromagnetic force adjusted easily by changing controller's parameters on-line.Therefore, it is significance that magnetic suspension isolator is applied in the passive vibration isolation system with multiple complex excitations to improve low-frequency vibration isolation performance. However, under the multiple complex excitations, the working-point of the magnetic suspension isolator fluctuates in wide range, which leads to the great nonlinearity. Moreover, there is strong coupling among of the excitations sources. There exists strong coupling among of magnetic suspension isolators. The coupling also exists between excitations sources and magnetic suspension isolators. These problems can not be solved by existing magnetic suspension isolation's theory and model. Therefore, in the project, the modeling of magnetic suspension isolator under multiple complex excitations is proposed, the electromechanical coupling dynamics model under multiple complex excitations is built and its control mechanism is presented. These studies establish the theoretical foundation for application of magnetic suspension technology to the vibration isolation system under multiple complex excitations.

潜艇声隐身性能的好坏对我国国防安全具有极其重要的意义。随着潜艇的发展，其内部机械设备的结构和激励方式越来越复杂，由于空间和重量所限，很多设备刚性或弹性安装在一起共同组成多源复杂激励的隔振对象。主动隔振技术能够克服被动隔振技术低频及谐振区隔振性能差的缺陷。与其它主动隔振技术相比，磁悬浮隔振技术具有频响范围宽、响应快、高可靠性和电磁力随控制参数易于调控的优势。应用磁悬浮隔振器能够有效解决多源复杂激励隔振系统隔振性能不足的问题。然而在多源复杂激励下，磁悬浮隔振器工作点变化范围大，导致强烈的非线性，且多个激励源之间、多个磁悬浮隔振器之间及激励源与磁悬浮隔振器之间存在耦合，现有的磁悬浮隔振理论与模型不能满足要求。为此，本项目拟研究多源复杂激励下磁悬浮隔振器建模，建立多源复杂激励下磁悬浮隔振系统非线性机电耦合动力学模型并研究其控制机理，为磁悬浮隔振技术在多源复杂激励隔振系统中的应用奠定理论基础。

随着舰船的发展，舰船内部的机械结构越来越复杂，由于空间和重量所限，很多机械设备（振源）刚性或弹性安装在一起，且每个设备产生振动激励信号的幅值、相位和频率及方向都不相同，这些激励信号混合叠加在一起，使得整个隔振对象上的激励信号复杂多变，构成了一个多源复杂激励隔振对象。考虑到主动隔振技术的优势，研究多源复杂激励下的主动隔振理论方法与技术，是有效隔离舰船机械振动，降低舰船机械噪声的关键。磁悬浮隔振器由被支承对象、电磁铁、传感器、控制器和功率放大器等组成，与其他主动隔振器相比具有频响范围宽、寿命长、响应快、无接触、且电磁力及支承参数（刚度，阻尼等）随控制参数的变化易于调控的优势，是一种较理想的主动隔振器。本项目设计了一种磁悬浮主动隔振器，将设计的磁悬浮隔振器应用到多源复杂激励隔振系统组成多源复杂激励磁悬浮主动隔振系统，针对多源激励下，磁悬浮隔振器的非线性、磁滞加剧，会影响到主动隔振效果，尤其是在工作频率较高时，采用传统的解析方法很难精密描述磁悬浮隔振器力-电流-位移之间关系的动态模型，而实验数据包含模型全部特征，因此，本项目采用人工神经网络对磁悬浮隔振器动态电磁力进行模型辨识，为了达到较高的辨识精度，分别采用BP、遗传算法及混合算法对人工网络进行训练，结果表明混合算法得到模型的最大偏差仅约为BP算法均方差的三分之一和MGA算法均方差的十分之七，能够满足磁悬浮隔振器动态电磁力模型辨识需求。 建立多源激励下主动隔振系统模型是主动隔振的前提和基础。针对不同的主动隔振系统分别采用解析方法和模型辨识得到相应的系统模型，并根据不同的隔振的评价准则，提出了两种不同的主动控制算法：（1）基于最小输出力的LQR主动隔振控制策略，Q与R矩阵的确定是LQR控制的关键，控制中Q和R矩阵通过全局优化的多种群的遗传算法优化得到。（2）基于加速度反馈的PID控制算法，控制中PID参数通过动态惯性权重因子的改进粒子群算法优化得到。针对不同系统的控制算法，仿真和实验结果均表明，在正弦、扫频、随机及冲击激励下磁悬浮主动隔振系统与被动隔振系统相比，隔振效果均提高60%以上，验证了控制模型及控制参数的有效性，为磁悬浮隔振技术在多源复杂激励隔振系统中的应用奠定理论基础。