液压伺服阀阀芯的动态特性分析与多目标优化

Dynamic Characteristic Analysis and Multi-Objective Optimization of Hydraulic Servo Valve Spool

为了提高液压伺服阀的动态响应特性,对液压伺服阀的阀芯结构进行了多目标优化研究,建立了阀芯结构参数与作用力之间的数学模型。以阀芯动态响应的超调量、振荡次数和上升时间作为优化目标,以阀芯的优化结构参数作为设计变量,数学地描述了阀芯动态特性多目标优化问题。分别采用NSGA-Ⅱ、SPEA2两种多目标进化算法与Simulink相结合对阀芯进行优化,评估了两种多目标进化算法的表现,得到了阀芯的最优设计参数。采用CFD、Simulink仿真验证了优化效果,结果表明:对应液压伺服阀入口压力工况为7、14、21 MPa时,作用在优化后阀芯上的稳态液动力相比优化前下降了37.10%、34.39%、30.53%;优化后的上升时间平均降低了3.77 ms,平均改善了61.74%;优化后的超调量平均改善了9.41%。

In order to improve the dynamic response characteristics of the hydraulic servo valve,a multi-objective optimization study is conducted on the spool structure of the hydraulic servo valve.A mathematical model between the structural parameters of the spool and the force acting on the spool is established.The multi-objective optimization problem of the dynamic characteristics of the spool is described mathematically with the overshoot,number of oscillations and rise time of the spool as the optimization objectives and the structural parameters of the spool as the design variables.Two multi-objective evolutionary algorithms,namely NSGA-Ⅱ and SPEA2,are employed in combination with Simulink to optimize the spool.The performances of these two multi-objective evolutionary algorithms are evaluated and the optimal design parameters for the spool are determined.CFD and Simulink simulation are employed to verify the optimization.The results show that when the inlet pressure of the servo valve is set at 7 MPa,14 MPa and 21 MPa,the steady-state flow force acting on the optimized spool decreases by 37.10%,34.39%,and 30.53%compared with unoptimized spool.The optimized rise time is reduced by an average of 3.77 ms and improved by an average of 61.74%.The optimized overshoot is improved by an average of 9.41%.