【作者】 陈飞；

【导师】 吴金波；

【作者基本信息】 华中科技大学 ， 轮机工程系， 2013， 硕士

【摘要】 目前，国内研制的阀门测试系统大多是针对小流量的，以液压油为工作介质的阀门。本文以工控机和PLC为控制核心，构建了一整套大流量水路阀门的性能测试系统，为测试新型水路阀门性能参数提供了可靠的实验手段。论文主要完成了以下工作：1、根据水路阀门测试系统的技术要求，设计了气路及水路管道系统，提出了气液混合压力控制策略。管路系统主要包括：两个20m3的大型压力筒、四个气路流量调节阀、两台离心泵、一台柱塞泵和高压气源。实验时，采用四个气路流量调节阀分别控制被试阀进出口处两个20m3的大型压力筒的进排气，从而控制两个压力筒内部压力差。同时控制两离心泵和柱塞泵将被试阀出口处压力筒内部的水泵至被试阀进口处压力筒内，增加系统有效试验水量储备。从而使得系统在保证水路阀门测试所需大流量的同时，能够精确控制被试阀两端的压差。2、借助AMESim仿真软件，构建了阀门测试系统的模型，通过数值模拟确定了系统参数，验证了控制策略的可行性。对于气液混合仿真系统，气液交界面的模型建立是一难点问题。本文采用气动缸和液压缸来模拟气液交界面处的气压力和液压力，通过两缸活塞杆的刚性连接来实现两种介质间的压力传递。3、气动流量调节阀是本系统实现精确压差控制的关键执行机构，为解决其在实际使用过程中的迟滞问题，本文采用Knocker迟滞补偿方法，控制流量调节阀在需要动作的方向上提前动作，从而消除气动流量调节阀动作的滞后问题，提高系统压力控制精度，消除系统震荡。同时为降低Knocker迟滞补偿方法带来的阀门动作频率过快带来的负面影响，根据系统允许误差，设定一个阈值。当被试水路阀门两端压差误差在阈值内时，取消Knocker迟滞补偿。4.、完成了整套阀门测试系统的编程及调试工作。试验结果验证了本文所提设计方法及控制策略的有效性。更多还原

【Abstract】 At present, we have researched and development a few valve testing systems. Unfortunately,most of their working medium was hydraulic oil, and their flow is very small. This paper, we takethe industrial control computer and PLC as the core of the control system. Then, we build a completepressure and water control system for the testing of large flow waterway valves. By the testingsystem, we can gain the experimental data of newly developed valve. Than we can gain theperformance parameters of the valve and carry out further development work on the valve byanalyzing the experimental data. The result of this experiment proves the testing system to bepractical. The work this paper finished is as follows.First, according to the water valve test requirements, a set of air-water mixture pressure pipelineneed to be designed. Through the calculation, determine the initial parameters of the system. At thesame time, proposed the strategy of the pressure controlling of the gas-liquid hybrid. The pipelinesystem comprises two20m3large pressure cylinders, four gas flow regulating valve, two centrifugalpumps, one piston pump and a high-pressure gas source. When the valve is testing, four gas flowregulating valve are respectively using to control the intake and exhaust of two20m3large pressurecylinders. In the provision of enough water the large flow water valve testing required, the precisecontrol of the pressure difference between the ends of the tested valve is needed, so as to meet thetest requirements.Second, the AMESim model of the designed the water-air mixing pressure system isconstructed. After the simulation calculation of the system is done, we can ensure that the system iseffective and system parameters are right. In the simulation of the water-air mixing pressure system,it is hard to select model for air-water interface. This paper, we take two plunger cylinders as themodel of the chamber, and take the piston whose mass is zero as model of the air-water interface.Third, In order to solve the lag problem of the practical use of the aerodynamic flow regulatingvalve, this paper adopts Knocker hysteresis compensation method, controls flow regulating valvetaking advance action in the direction of needing move. Thereby we can remove the lag of thepneumatic flow regulating valve, improve the accuracy of pressure control and eliminate the systemshock. At the same time, according to the system permissible error, a threshold is set to reduce thenegative effect brought by the Knocker hysteresis compensation method which brings the fastfrequency of the valve action. When the error of the pressure difference between the ends of thetested valve across threshold, the Knocker hysteresis compensation will be canceled to reduceaerodynamic flow regulating valve wear.Last, we finish a set of control subsystem of the valve testing system including the controlprogram of Siemens PLC and the control-display program of the industrial computer. Complete the system debugging. The experimental results validate the effectiveness of the proposed designedmethod and controlling strategy.更多还原