【作者】 赵航；

【导师】 李军；

【作者基本信息】 哈尔滨工业大学 ， 机械工程， 2015， 硕士

【摘要】 电液伺服振动试验台能够模拟正弦、随机等振动环境,适用于检测汽车零部件的共振频率点以及疲劳寿命等多种性能指标。其中,正弦振动测试是一种典型的振动形式,在振动环境模拟的实验中应用非常广泛,但是在正弦加速度控制过程中,电液伺服振动试验台输出的正弦加速度信号往往存在幅值误差、相位滞后以及含有高次谐波等问题。为此,本文深入的研究了汽车零部件正弦振动试验台的幅相控制策略和谐波抑制策略。本文首先根据电液伺服正弦振动试验台的动力机构参数,在simulink中基于原始方程建立了伺服系统的非线性模型,该模型充分考虑了摩擦力等非线性环节,可以准确的反映实际情况,是后续仿真研究的基础。然后,本文对液压伺服系统的动力机构做了线性化分析,并基于线性化模型设计了三状态控制器。为解决正弦振动试验台的输出信号存在幅值误差及相位滞后的问题,本文分别研究了两种幅相控制方法,分别是基于系统辨识和离线迭代的控制策略和基于LMS算法的自适应控制策略,并在simulink中设计了自适应幅相控制器。最后,本文对两种幅相控制策略进行了仿真分析,并比较分析了两种算法各自的特点。为解决正弦振动控制过程中试验台的输出加速度波形存在波形畸变的问题,本文首先从液压伺服系统的时变性及非线性两个方面对引起波形畸变的因素进行了详细的分析,探讨了谐波抑制的可选方案。最后,为了降低加速度输出波形的谐波含量,本文设计了自适应谐波抑制控制器,该控制器通过带通滤波器得到谐波信息,并基于LMS算法自动调整陷波器的权值系数,从而消除输出加速度响应中存在的某一次谐波,达到降低波形失真度的目的。为进一步研究本文所提控制策略在工程实际中的适用性,本文首先安装调试了电液伺服正弦振动试验台,并基于快速控制原型技术验证了本文所提的幅相控制策略及谐波抑制控制策略。从实验结果来看,本文在仿真验证得到的结论是正确的,这也证明了所提控制算法的实用性。更多还原

【Abstract】 The electro-hydraulic servo vibration test equipment can simulate many kinds of vibration environment such as sine, random and so on, which can be applied to detect the resonance frequency and fatigue life of the automobile components. The sine vibration test is a typical form of vibration, which is widely used in the vibration environment simulation experiment, but in sine acceleration process control, the sine acceleration signals often exist amplitude error, phase lag and the harmonics, which will decrease the precision. For this purpose, the paper further studied the strategy of the harmonic cancellation strategy and the amplitude-phase control strategy for the sinusoidal vibration test.Firstly, according to the mechanism parameters of the electro hydraulic servo sinusoidal vibration test equipment, this paper established nonlinear mathematical model of the servo system based on primitive equation, the model considered nonlinear part such as friction, this model, which is the basis for the following simulation, can accurately reflect the actual situation. Then, the paper analyzes the mechanism of the hydraulic servo system, and designs the three state controller based on the linearization model..To solve the amplitude error and phase lag problem of the output sine acceleration signal, this paper research the amplitude-phase control strategy, which is the based on system identification and offline iterative, meanwhile, this paper research the other amplitude phase control strategy which based on LMS algorithm. After the simulation of two kinds of control strategies, this paper analysis the two algorithms.To solve waveform distortion problems of the output sine acceleration signal in the process of test. This paper analysis the factor from two aspects,which is time-varying factor and nonlinear factor of hydraulic servo control system, then this paper explores the options for the harmonic suppression scheme. In order to cancellate the harmonic, this paper researchs the adaptive harmonic suppression control strategy based on LMS algorithm.In order to verify the control strategy is correct, this paper developed adaptive amplitude-phase controller and adaptive harmonic suppression controller based on rapid control prototyping technology, and the experiment result is satisfacted, which indicate that the conclusion obtained in the simulation is right.更多还原