【作者】 王维锐；

【导师】 潘双夏； 冯培恩；

【作者基本信息】 浙江大学 ， 机械设计及理论， 2007， 博士

【摘要】 以车辆悬架系统中的被动减振器、半主动减振器和半主动悬架为研究对象，对被动减振器的物理参数建模、半主动减振器的安全冗余创新设计和新型半主动控制策略等进行了深入研究，主要涉及以下几个方面：提出一种改进的双筒式液压减振器建模方法。该模型中结构动力学子模型和流体动力学子模型采用经典的解析计算方法建立，但阀片(组)变形动态子模型采用基于薄板大挠度变形理论的数值计算方法建立。与传统的基于薄板小挠度理论的模型相比，所建立的阀片(组)变形动态子模型可以解决多片阀片间变形的耦合问题、更准确地描述不规则形状阀片的变形特性。仿真与实验数据的对比分析表明，改进的模型比传统计算模型能更准确地描述减振器的阻尼力特性和滞环特性。提出一种新的具有安全冗余功能的减振器结构形式，这一结构集半主动减振器的可控性和被动减振器的安全性于一体，能够在车辆悬架控制系统不能正常工作的情况下提供足够大的阻尼力，保证此时车辆的安全性和舒适性。这一结构比现有文献中类似结构更简单、能耗更低、安全性更高。针对此结构，进一步研究其动力学模型及电磁磁路和永磁磁路的设计模型。根据建立的设计模型进行了样机设计与试制，并对样机进行了台架试验，用实验数据验证了这一安全冗余结构和所建立的动力学和磁路设计模型的有效性和实用性。研究使用前述具有失效保护功能的磁流变液减振器的半主动悬架的控制策略。提出将具有清晰物理意义的负刚度减振理论应用于车辆半主动悬架的控制，并讨论其在基于磁流变液减振器的半主动悬架上的技术实现方法。将负刚度控制策略和天棚阻尼控制策略进行了比较分析，并通过搭建的1／4车垂向动力学实验系统进行了验证，结果表明负刚度半主动控制能更好的抑制振动对车身加速度和轮胎动位移的影响，并且结构更简单、成本更低。研究车辆1／4悬架性能实验系统中电液伺服阀控激振系统的控制策略和时域内路面不平度的台架复现方法。提出将自抗扰控制算法用于电液伺服阀控激振系统的控制，并与基于扰动观测器的控制策略进行了对比分析。仿真和实验结果表明，采用自抗扰控制算法时系统具有更高的稳态精度、对大范围的负载干扰和参数扰动具有更强的抑制作用。将时域内路面不平度的两种台架复现方法进行仿真和实验比较分析。结果表明采用谐波叠加法模拟产生的随机路面的精度优于线性滤波法。更多还原

【Abstract】 The research objects of this thesis are passive shock absorber, semi-active shock absorber and semi-active suspension of vehicle suspension system. Physics parameter based model of passive shock absorber, innovational mechanism with safety redundancy function, and new semi-active control strategy are studied.A new physics parameters based nonlinear complex model of passive shock absorber was presented. In the model, mechanical dynamics sub-model and fluid dynamics sub-model were modeled with analytic method, while the deformation dynamics sub-model of valve plate was modeled with numerical method based on plate large deformation theory. This complex physics parameter based nonlinear model takes account of the effect of gas pressure, effective bulk modulus of gas mixed oil, bulk modulus of cylinder shell, leak, friction, etc. Validation with test data shows that the model can simulate the damping character and hysteresis of shock absorber well.An innovational mechanism with safety redundancy function of magneto-rheological fluid shock absorber was presented. This fail safe magneto-rheological fluid shock absorber gives attention to controllability of semi-active shock absorbers and safety of passive shock absorbers. Dynamics model, electromagnetic model and permanent-magnetic model were given. Based on the models, prototype shock absorbers were designed and manufactured. Test data show that the models are effective and precision.A new semi-active control strategy based on the new designed shock absorber was studied. The negative stiffness control strategy with legible physics signification was introduced to control the semi-active suspension. The negative stiffness control strategy was compared with sky hook control strategy, and the compare results were validated on the quarter car vertical dynamics test system.A quarter car vertical dynamics test system was established. Two key technology of the test system were discussed, they are robust controller of electro-hydraulic position servo system and methods of reproduction of road roughness in time field.更多还原