The Automatic Control And Performance Characteristics Analysis Of New Type Piston Gauge

Pressure is a very important parameter in industrial production and daily life. Pressureinstrument, is the detection tool of pressure parameters, and its accuracy, reliability and otherperformance indicators will be affected by these factors such as application circumstance,frequency of use, maintenance and storage condition, so it is necessary for the pressureinstrument to be verified or calibrated periodically. Piston gauge is the measurementstandards that used very widely in the field of pressure metrology, but in its practicalapplication, the verification operations is always carried out manually, which causing highlabor intensity, low performance efficiency, and fail to meet the pressure instrument testdemand of modern industry.Non-rotating piston gauge is a new type of piston gauge, which is improveed both instructure and working mode based on the traditional piston gauge. It has the followingadvantages: Non-rotating piston system eliminates the procedure of turning piston, simplifythe operation process; electrical separate weight load system makes the control of weightloading process more flexible and the execution more quickly; pressure calibration becomesmore precise and more smooth by the introduce of servo motor driving. Non-rotating pistongauge passes the advantages of high accuracy, good stability in traditional piston gauge, alsohas the characteristics such as flexible control, higher automation level, quickly andsmoothly action, improve the verification efficiency and measurement accuracy.This paper introduced the working principle of non-rotating piston gauge firstly,analyses the mechanical structures and electrical component of non-rotating piston system,electrical separate weight load system and servo motor driving pressure calibration system.After that discussed the design of computer control software, focusing on the design idea andthe implementation method of each function modules. The software is designed based on therelated verification regulations, considering the characteristic of this new type piston gauge.The software has good man-machine interface, realizes major functions such as equipmentrunning status monitoring, standard pressure generation and release, automatic servopressure calibration and pressure sensor data collection. Then the paper established the mathematical model of automatic servo pressurecalibration system and the digital simulation model based on Simulink, and made study onthe system’s response to the typical interference load input under different control methodsthrough experiment and computer simulation. The result proved models are right and thecontrol method of incremental PID with dead band can be applied to the automatic servopressure calibration system.Finally, the paper established the pressure measurement model through the analysis ofthe non-rotating piston gauge system, and developed the sensitive coefficient of each inputaccording to the law of propagation of uncertainty, provided calculation method of pressuremeasurement uncertainty for the piston gauge. The research results of this paper laid thefoundation for the application in practice of new type piston gauge.