【作者】 王曦；

【导师】 朱建新；

【作者基本信息】 江苏大学 ， 动力机械及工程， 2003， 硕士

【摘要】 内燃机振动的主要类型是整机振动和扭转振动，其中内燃机整机振动强度是内燃机总体振动品质的反映。传统的整机振动控制方法被动控制只能适用于单一频率的振动，无法满足整机宽频带振动的要求；而主动控制则可以通过外界能量主动改变控制系统的某些参数来适应内燃机整机振动的变化，因此能达到更好的减振效果。 本文以4135型柴油机为研究对象，建立了内燃机整机振动六自由度的数学模型并进行了动力学分析，明确了整机振动的主要干扰力，由此建立了占主导地位的内燃机整机垂向振动控制系统的数学模型，提出了一种新的内燃机整机振动主动控制减振系统。在主动控制的基础上，采用了模糊控制的算法，设计了内燃机整机振动模糊控制器，改进了传统控制方法在处理振动复杂性、非线性和不确定性等方面的缺陷，通过测量内燃机转速和内燃机整机振动速度信号，动态地改变动力减振器的刚度，使减振器的固有频率跟随内燃机整机振动激励频率的变化，达到降低内燃机振动的目的。以Matlab+Simulink为仿真工具，设计了模糊控制系统和被动控制系统两类不同的仿真模型，并进行了对比仿真和结果分析，在此基础上，设计开发了以80C196KC单片机为主控器件的模糊控制系统，进行了控制系统的软、硬件设计，最后对所设计的模糊控制系统进行了台架实验，实验结果表明模糊控制系统能有效地降低了内燃机整机振动的强度，达到了国标规定的合格级，证明了本文建立的数学模型和模糊控制算法是正确可行的，在内燃机振动控制策略方面作了一个积极的探索和研究。更多还原

【Abstract】 I.C. Engine has two major kinds of vibration: the body vibration and torsion vibration. And the intensity of engine body vibration is the symbol of engine total vibration. Traditional control method over body vibration-passive control only can be adapted to single frequency of vibration, which can not meet the requirement of broad frequency band of body vibration. On the other hand, active control over body vibration can adjust certain parameter of control system to get adapted to the change of I.C. Engine Body Vibration, so it is able to reach better control effect.This paper takes the 4135 diesel engine for research example, establishes 6-degree mathematic model of I.C. Engine Body Vibration and conducts kinetics analysis. Then the control model of engine vertical vibration which dominates among all kinds of engine vibration is established. So we present a new control system for I.C. Engine Body Vibration. We apply fuzzy control theory to active control over engine body vibration, design fuzzy control system which combines intelligent control with feedback control. This control strategy mends the flaw of complexity, nonlinear and uncertainty when we use traditional control method. By measuring rotate speed and vibration speed of I.C. Engine, the fuzzy control system can adjust spring firmness of shock absorber, so it can fit the change the I.C. Engine Body Vibration. We use Matlab and Simulink as tools to simulate two different kinds of control system. Then based on the simulation results analysis, we design and develop a fuzzy control system in which 8098 chip microcomputer plays the major role. Finally we conducts rig test with fuzzy control system. The test results indicate fuzzy control system is able to lower intensity of body vibration and the national standard on the vibration eligible class of the engine is met. It is demonstrated that the mathematical model and fuzzy control arithmetic presented by the paper are accurate and reliable, which make an active seek and research on control strategy of engine vibration.更多还原