混凝土泵车臂架EHA系统控制策略研究

Exploring Control Strategies for EHA System in Concrete Pump Truck Boom

针对混凝土泵车臂架系统响应慢、动态性能差等问题,提出了采用电静液执行器(EHA)代替臂架中的传统液压系统,从而提高系统响应速度,减少臂架振动。首先介绍了EHA的工作原理与数学模型,提出了基于S曲线前馈补偿的模糊PID控制策略,其次利用AMESim与MATLAB软件搭建了混凝土泵车臂架的机械—液压—控制联合仿真模型,通过对臂架油缸伸出和缩回过程的阶跃控制仿真和正弦控制仿真,对比PID控制、模糊PID控制与基于S曲线前馈补偿的模糊PID控制3种控制策略的仿真结果,结果表明,基于S曲线前馈补偿的模糊PID控制下系统响应时间减少50%左右,超调量减少67%左右,速度跟踪误差减少50%左右。搭建EHA试验样机进一步验证基于S曲线前馈补偿的模糊PID控制策略的有效性。

The article addresses the issues of slow response and poor dynamic performance in the boom system of concrete pump trucks.It proposes the use of electro-hydrostatic actuators(EHA)instead of traditional hydraulic systems in the boom to improve system response speed and reduce boom vibrations.Firstly,the working principle and mathematical model of EHA are introduced,and a fuzzy PID control strategy based on S-curve feedforward compensation is presented.Furthermore,a combined mechanical-hydraulic-control simulation model of the concrete pump truck boom is constructed using AMESim and MATLAB software.The simulation results of step control and sinusoidal control of the boom cylinder extension and retraction processes are compared among three control strategies:PID control,fuzzy PID control,and fuzzy PID control based on feedforward compensation,it is demonstrated that the system response time is reduced by about 50%,overshoot is reduced by about 67%,and speed tracking error is reduced by about 50%under the fuzzy PID control based on S-curve feedforward compensation..Furthermore,an EHA experimental prototype is built to further validate the effectiveness of the fuzzy PID control strategy based on S-curve feedforward compensation.