针对数字比例阀在煤矿井下钻机电液系统应用中特性开发不足的问题,从数字比例阀的原理出发,构建其数学模型,阐述先导级和主阀之间的耦合关系,发现先导流量是决定主阀静动态特性的关键指标。研究建立了数字比例阀的AMESim模型,仿真结果表明,控制数字比例阀的PWM信号频率为20Hz时,占空比对流量的线性调控范围为0.2~0.8,主阀输出流量波动幅值为3.16L/min,数字比例阀静动态特性表现良好。调整好PWM信号频率后将数字比例阀运用于钻机给进回路中,经过测试试验,数字比例阀控给进回路的钻机位移误差较传统阀控回路由2.8%提升至1.9%。

 In response to the problem of insufficient development of characteristics in the application of digitalproportional valves in the electro-hydraulic system of coal mine underground drilling rigs, starting from the principleof digital proportional valves, a mathematical model was constructed to explain the coupling relationship between thepilot stage and the main valve. It was found that the pilot flow rate was a key indicator that determines the staticand dynamic characteristics of the main valve. A AMESim model for a digital proportional valve was established,and simulation results showed that when the PWM signal frequency of the digital proportional valve was controlled at20 Hz, the linear control range of the duty cycle flow rate was 0. 2 ~ 0. 8, and the output flow fluctuation amplitudeof the main valve was 3. 16 L/ min.The static and dynamic characteristics of the digital proportional valveperformed well. After adjusting the PWM signal frequency, the digital proportional valve was applied to the feedcircuit of the drilling rig. After testing experiments, the displacement error of the drilling rig controlled by thedigital proportional valve in the feed circuit was increased from 2. 8% to 1. 9% compared to the traditional valvecontrolled loop.