自由活塞直线发电机电液机械系统非线性动力学建模与响应分析

Free-piston Linear Generator is non-linear system, which couples several physical fields. After adding a hydraulic component to balance the system, it is now getting more complex to describe its dynamic characteristics. The dynamic modelling and analysis methodology on this stage usually linearizes each non-linear factor, which makes it difficult to predict the system response precisely, and prevents the further investment of the system operation characteristics. As a result, in order to improve the prediction accuracy of the system response and contribute the technical development the free-piston linear generator, it is necessary to establish a non-linear dynamic model which takes both of the system non-linear factors and coupled characteristics.. In order to accomplish the research, the following work need to be finished: 1) provide an accurate and validated description of each non-linear factor; 2) develop a non-linear dynamic model for the system based on the constitutive relations of the partial and the whole system; 3) present a mathematical and experimental research on the model response in connection with the specific forms of non-linear factors. The above research work aims to develop a non-linear dynamic response model, which is based on the experimental results and able to reflect the system constitutive relations. This will provide a valuable guidance and present a general analysis methodology for the future research.

自由活塞直线发电机是多物理场耦合的非线性系统，为满足整机振动平衡要求而加入液压组件后，精确描述整个系统的动力学特征变得更加复杂。目前的动力学建模与分析方法普遍将各非线性因素简化，使对系统响应的精确预测变得困难，阻碍了对自由活塞直线发电机运行机理的深入研究。因此，考虑系统非线性因素及耦合特征建立非线性动力学模型是提高系统响应预测精度、推动自由活塞直线发电机整体研究工作的必要手段。. 要实现这一目标需要完成以下工作：1）对系统各非线性因素给出精确、符合实验结果的表征；2）研究局部、系统本构关系，据此建立系统非线性动力学模型；3）针对非线性具体形式对模型响应进行数值与实验研究。以上工作旨在建立依托实验现象、深度体现系统本构特征、具有较强指导意义的非线性动力学响应模型，并形成适用的分析方法。

自由活塞直线发电机是多物理场耦合的非线性系统，为满足整机振动平衡要求而加入液压组件后，精确描述整个系统的动力学特征变得更加复杂。目前的动力学建模与分析方法普遍将各非线性因素简化，使对系统响应的精确预测变得困难，阻碍了对自由活塞直线发电机运行机理的深入研究。因此，考虑系统非线性因素及耦合特征建立非线性动力学模型是提高系统响应预测精度、推动自由活塞直线发电机整体研究工作的必要手段。本项目通过理论结合实验的方法，对自由活塞直线发电机电液机械系统非线性动力学建模与响应分析开展了研究，揭示了自由活塞直线发电机电液机械系统的变阻尼电机阻力非线性特征，获得自由活塞直线发电机电液机械系统的非线性液压弹性力与摩擦力的精准数学表征，对比分析了自由活塞直线发电机电液机械系统在有无考虑非线性时的动力性响应，并通过实验验证自由活塞直线发电机电液机械系统的非线性特性。通过本项目的研究，建立了依托实验现象、深度体现自由活塞直线发电机系统本构特征、具有较强指导意义的非线性动力学响应模型，并形成了适用的分析方法。