基于PD控制的液压系统的建模和分析

Modeling and Analysis of Hydraulic System Based on PD Control

针对液压系统的稳定性、快速性和准确性问题,提出通过合理选择控制参数来调节系统动态特性的方法。首先,对液压系统进行建模,然后利用AMESim软件对其进行仿真,同时在时域和频域内分别分析PD控制器各增益系数对系统性能的影响。研究结果表明,比例环节(P)能够改变系统的稳定性,但所需调节时间比较长,系统振荡剧烈,且随着比例系数的增大系统稳定性变差。当加入微分环节(D)时,系统的振荡次数减少,调节时间变短,响应速度提高,但系统的抗干扰能力减弱。最后根据控制系统中给出的幅值裕度和相位裕度范围确定控制器各增益系数,可以使系统快速获得满意的动态特性,为液压系统动态性能的调试提供了一种参考方法。

Aiming at the stability,rapidity and accuracy of the hydraulic system,this paper proposes a method to adjust the dynamic characteristics of the system by reasonably selecting the control parameters.Firstly,the hydraulic system is modeled,and then simulated by AMESim software.The effects of the gain coefficients of the PD controller on the system performance are analyzed in the time domain and the frequency domain.The research results show that the proportional link(P)can change the stability of the system,but the required adjustment time is longer,the system oscillation is severe,and the system stability deteriorates with the increase of the proportional coefficient.When the differential link(D)is added,the number of oscillations of the system is reduced,the adjustment time is shortened,the response speed is increased,but the anti-interference ability of the system is weakened.Finally,according to the amplitude margin and phase margin range given in the control system,the gain coefficients of the controller are determined,which can make the system quickly obtain satisfactory dynamic characteristics and provide a reference method for debugging the dynamic performance of the hydraulic system.