基于压电效应的车辆振动能量回收悬架系统动力学研究

According to present situation that the vehicle vibration energy recovery methods mainly include mechanical type and electromagnetic type，the method using direct piezoelectric effect of piezoelectric material will be researched to recover vehicle vibration energy and generate damping for reducing vehicle vibration at the same time , and its principle will be expounded. The scheme of piezoelectric mechanism will be put forward to covert the mechanical energy to electrical energy and generate damping for reducing vibration. According to the characteristic of generating electricity by piezoelectric vibration and damping for reducing vehicle vibration, the transmission mechanism scheme of pinionandrack using with cam will be put forward to transform the body vibration displacement and velocity to the vibration displacement and frequency of piezoelectric element, and the relation between body vibration velocity and the amount of recovered vibration energy will be set up. The vibration energy recovery suspension system based on piezoelectric effect will be analyzed for its damping characteristic, stiffness characteristic, vibration energy recovery characteristic and riding comfort of vehicle equipped with this suspension system. The effect of parameters of piezoelectric mechanism and transmission mechanism on damping characteristic, stiffness characteristic, vibration energy recovery characteristic of suspension system and vehicle riding comfort will be analyzed. The research achievement of this project will provide the supplement for vehicle vibration energy recovery theory and vehicle damping theory. It accords with requirement for vehicle to save energy and protect environment and will have wide application prospects with Chinese auto industry developing rapidly and continuously.

针对目前车辆振动能量回收方法主要有电磁式和机械式的现状，本项目拟研究利用压电材料的正压电效应回收车辆振动能量并产生减振所需阻尼的方法，并阐明其原理。拟提出压电机构方案将车辆的振动能量转换为电能并产生减振所需阻尼；针对压电元件的振动发电特性以及车辆减振所需阻尼的特点，拟提出齿轮齿条结合凸轮的传动机构方案将车身振动的位移和速度转换为压电元件振动的位移和频率，建立车身振动速度与振动能量回收量之间的关系；分析基于压电效应的振动能量回收悬架系统的阻尼特性、刚度特性、振动能量回收特性及安装此悬架系统车辆的平顺性，分析压电机构和传动机构参数对悬架的振动能量回收特性、阻尼特性、刚度特性和车辆平顺性的影响。本研究项目的研究成果是对车辆振动能量回收理论和阻尼理论的补充和完善，符合当今社会对车辆节能和环保的要求，在我国汽车产业持续高速发展的背景下，具有广阔的应用前景。

如果能将车辆的振动能量进行回收再利用，对减小车辆的能源消耗及尾气排放有重要意义。针对目前车辆振动能量回收研究方法主要有电磁式和机械式的现状，本项目开展了基于压电效应的车辆振动能量回收新方法的研究。. 项目确定了压电馈能式减振器的结构方案，压电馈能式减振器由减振器本体、万向传动轴和压电机构组成，万向传动轴将减振器本体和压电机构连接。减振器本体产生阻尼的同时将车身相对于车桥的直线运动转换为压电机构的旋转运动，压电机构将机械能转换为电能。压电馈能式减振器将车辆振动能量转换为电能的同时衰减车辆的振动，解决了将压电元件融入悬架系统的问题。. 项目建立了压电振子的振动数学模型，对压电振子的自由振动和强迫振动进行了分析。建立了压电振子的机电能量转换数学模型，分析了压电振子的发电特性及其影响因素。设计了振动能量回收电路，分析比较多种振动能量回收电路的特性。建立了压电机构的数学模型，对压电机构的发电特性进行了分析。研究结果表明，存在基板厚度与压电梁总厚度的最佳比值使压电振子输出电能最大，双晶压电梁的最佳厚度比为0.3且不受材料参数的影响；n个压电振子串联结构对应的最优负载是并联结构对应的最优负载的n的平方倍；压电机构接口电路的最大储能功率为769.4mW，储能效率为72.5%。. 项目建立了减振器本体和压电机构的阻尼特性数学模型，分析了减振器本体和压电机构的阻尼特性，综合减振器本体和压电机构的阻尼特性，得到了压电馈能式减振器的阻尼特性，分析了压电机构的阻尼占悬架阻尼的百分比。建立基于压电馈能式减振器的样车的仿真模型，对其平顺性进行分析。分析结果表明，压电机构产生的阻尼约占车辆减振所需阻尼的6.9%-9.3%，压电机构的刚度对车辆悬架刚度的影响小于1%。. 本研究项目的研究成果是对车辆振动能量回收理论和阻尼理论的补充，符合当今社会对车辆节能和环保的要求，在我国汽车产业持续高速发展的背景下，具有广阔的应用前景。