论文部分内容阅读
为了探究闭环控制对于压路机行走速度稳定性的改善作用,采用理论分析与仿真相结合的方法对压路机行走系统进行了分析。根据压路机行走液压系统图及各液压元件的工作特性建立了传递函数模型,并据此推导出了控制电信号及行走负载分别与行走速度响应之间的传递函数关系。结合闭环比例、积分、微分(PID)控制特点对压路机行走系统传递函数模型进行了改进,得到了闭环PID控制下压路机行走系统传递函数模型。在理论推导的基础上,对某12t双钢轮压路机进行了行走试验,将仿真速度曲线与实际速度曲线进行时域及频域对比,并对现有模型进行了仿真分析,探究了闭环PID控制对行走系统特性的影响。研究结果表明:仿真模型能够很好地复现波动负载下压路机实际行走速度的变化规律,在加入PID闭环控制后,在保持速度平均值不变的基础上,压路机行走过程中的速度稳定性有所提升,系统阶跃响应中的超调和振荡现象得到了明显的抑制,稳定时间有所改善,系统的响应准确性更好;将闭环控制用于压路机行走系统中,能够有效地改善压路机平稳作业过程中的速度稳定性,提高压实作业质量。
In order to explore the effect of closed-loop control on the stability of road roller’s walking speed, the road roller system was analyzed by the combination of theoretical analysis and simulation. The transfer function model is established according to hydraulic system diagram of the road roller and the working characteristics of the hydraulic components, and the transfer function between the control electric signal and the walking load and the walking speed response is deduced. The transfer function model of road roller walking system is improved with closed-loop proportional, integral and derivative (PID) control characteristics, and the transfer function model of roller walking system under closed-loop PID control is obtained. Based on the theoretical deduction, the running test of a 12t double drum roller is carried out. The simulation of speed curve and actual speed curve is carried out in time domain and frequency domain. The existing models are simulated and analyzed. The closed-loop PID control Impact on walking system characteristics. The results show that the simulation model can well reproduce the variation law of the actual walking speed of the road roller under the fluctuating load. After adding the PID closed-loop control, while keeping the average value of the speed unchanged, the speed stability of the road roller during walking The overshoot and oscillation in the system step response are significantly suppressed, the stabilization time is improved and the response accuracy of the system is better. When the closed-loop control is used in the roller traveling system, the smooth operation of the roller can be effectively improved The speed of the process stability, improve compaction quality.