大型调节阀死区的颤振补偿研究

针对大型电液调节阀的死区是导致其调节滞后的主要因素,分析了调节阀死区的产生原因,研究了在调节阀的执行机构叠加高频颤振进行死区补偿的机理。利用AMESim仿真软件,建立了电液调节阀的死区补偿模型,并对该模型进行了实验验证。在此基础上,讨论了颤振信号的幅值、频率和均值对死区补偿效果的影响。结果表明,通过叠加适当的高频颤振信号,使电液调节阀的执行机构始终处于微小的颤振状态,可以有效克服死区的影响,改善调节阀的动态响应特性,实现对调节阀死区的有效补偿。

Dead zone compensation for a large-size control balve based on dither effect

The dead zone of an electro-hydraulic control valve is the major reason resulting in hysteresis of a mixed-gas pressure regulation.The generation of the valve dead zone was analyzed.The dead-zone compensation mechanism with high-frequency dither signals acting on the actuator of the control valve was discussed.By use of AMESim simulation tool, the physical model of the dead-zone compensation for the electro-hydraulic control valve was established, and the model was verified by the experiments.Based on the physical model, the dither-signal parameters affecting the compensation performance were investigated.The results showed that the adverse effects of the valve dead zone are obviously reduced by adding dither signals to the actuator to keep it vibrating lightly and persistently, the dynamic response characteristics of the control valve are improved, and the dead-zone compensation is obtained.