改进PSO算法优化的电液位置伺服系统自抗扰跟踪控制

Auto Disturbance Rejection Tracking Control of Electro-hydraulic Position Servo System Optimized by Improved PSO Algorithm

针对电液位置伺服系统由于参数不确定性、非线性、复杂时变性而导致的响应速度慢、跟踪精度低、抗干扰能力差的问题,提出一种具有更高跟踪精度及抑制抖振能力的改进PSO算法优化的自抗扰控制(Improved-PSO auto disturbance rejection control,IPSO-ADRC)方法。首先,建立电液位置伺服系统的误差状态空间方程,采用3阶跟踪微分器、扩张状态观测器及状态误差反馈律构建自抗扰控制器模型;其次,分析惯性权重递减PSO算法存在的早熟、易陷入局部最小值等问题,综合考虑粒子迭代次数及当前粒子与全局最优粒子间距离两个因素对寻优结果的影响,提出一种改进PSO算法;最后,将改进后的PSO算法应用于所设计的自抗扰控制器中以提高控制性能。仿真及试验结果表明,相比于传统PID控制和常规自抗扰控制,采用改进PSO算法优化的自抗扰控制具有位置跟踪精度高、抗干扰能力好的优点。

To overcome the slow response speed,low tracking accuracy and poor anti-interference ability of an electro-hydraulic position servo system due to parameter uncertainty,nonlinear and complex time-variance,an improved PSO algorithm that has higher tracking accuracy and vibration suppression capability is proposed.Firstly,the error state space equation of the electro-hydraulic position servo system is established.Secondly,an auto disturbance rejection control model is constructed by adopting a third-order tracking differentiator,an expansion state observer and a state error feedback law.Thirdly,the premature and local minimum of inertia weight decreasing PSO algorithm is analyzed.Taking into consideration the influence of the number of particle iterations and the distance between the current particle and the global optimal particle on the optimization result,an improved PSO algorithm is proposed.Finally,the improved PSO algorithm is applied to the auto disturbance rejection controller designed in the paper to improve its control performance.The simulation and experimental results show that the improved PSO algorithm has the advantages of high position tracking accuracy and good anti-interference ability.