复合型流量计的测量模型

Measurement Model of Compound Flowmeter

在无载液压缸动态特性良好的基础上,将其与伺服电机控制的计量泵并联连接,设计一种复合型动态流量计,可实现对连续偏置的动态流量精确测量。计量泵调节无载液压缸的活塞位置的同时测量偏置稳态流量,无载液压缸测量高频的动态流量,解决了无载液压缸的行程受限问题。结合复合型动态流量计的结构特性,提出了一种新的泵控缸动平衡控制方案来调节液压缸的活塞位置,提高了活塞的控制和响应速度;同时针对流量测量中的流体泄漏建立流量泄漏补偿模型,使动态流量的测量更精确。搭建实验系统,利用LabVIEW编写实验程序,结合涡轮流量计进行稳态流量测量校准。实验结果表明:复合型流量计方案可行,在稳态流量的测量中可以实现高精度的测量,在动态流量测量中,动态性能良好。

Based on good dynamic characteristics of no-load hydraulic cylinder,a compound dynamic flowmeter is designed by connecting it in parallel with a metering pump controlled by servo motor,which can realize accurate measurement of dynamic flow with continuous bias.Metering pump is used to adjust piston position of no-load hydraulic cylinder and measure offset steady flow at the same time,and no-load hydraulic cylinder measures high-frequency dynamic flow,which solves the problem of no-load hydraulic cylinder's stroke limitation.Combined with the structural characteristics of compound dynamic flowmeter,a new pump-controlled cylinder dynamic balance control scheme is proposed to adjust piston position of hydraulic cylinder and improve control and response speed of the piston.A flow leakage compensation model is established for the fluid leakage in the flow measurement to make the dynamic flow measurement more accurate.Using LabVIEW platform write experimental program,and turbine flowmeter is used for steady-state flow measurement and calibration.The results show that the scheme of compound flowmeter is feasible,and it can achieve high-precision measurement in the measurement of steady-state flow.In the measurement of dynamic flow,compound flowmeter with good dynamic performance can effectively test dynamic flow.