阀芯位移 meaning in English

spool displacement
spool travel
spool traverse

Then pid flow rate control algorithm is introduced . all experiments made in this chapter are about measuring the valve parameters according to spool positions , single actuator flow rate control by the calculated flow rate feedback control method , free flow rate dividing control under the sufficient pump discharge flow rate situation , proportion flow rate dividing and flow rate dividing based on meter - in flow rate feedback control method under insufficient pump discharge flow rate situation . the results of all experiments proved that the method presented in this thesis is an effective way to overcome the unreasonable flow rate dividing when simultaneously operating multi - actuators with different inertia loads
第四章介绍了多执行器复合控制实验系统和实验方法；介绍了实验采用的流量控制的pid算法；并测定了执行器控制阀和阀芯位移相关的系数；做了单个执行器计算流量反馈流量控制、流量足够情况下多执行器流量任意分配、流量不足情况下多执行器按比例调节流量分配和多执行器进油侧流量反馈分流控制实验；通过实验说明了论文提出的分流控制方法能实现大小惯性负载复合操作时的合理分流。