Research On High Precision Electronic Pressure Gauge

A new type of electronic pressure gauge used in oil-well has been researched and designed in this thesis. How to improve the accuracy of the pressure gauge? A great of pressure gauges use high precision sensors rather than using advanced software approaches in home and abroad. This type of electronic pressure gauge is cheap in price, stable in performance and easy in maintenance because of using software approaches to improve the accuracy.Firstly, the working environments and principles of pressure gauge are analyzed, and the function and performance indicators of system are proposed in this thesis. Overall design has been finished according to these indicators.Secondly, the electronic pressure gauge has been designed by using the MicroConverter ADuC834 as the core, which includes power and battery management circuit, the pressure and temperature sampling circuits, USB/UART communication interface circuit, data storage circuit and clock wake-up circuit.In order to solve the problem of intercross sensitivity of pressure sensor by temperature, artificial neural network based on particle swarm optimization (PSO) has been adopted in this thesis. Because the PSO algorithm is easy to run into local minimal spot, the stretching technique has been applied to improved PSO algorithm. And the results of the data fusion shows that the method could improve the accuracy of pressure gauge from 4.2‰to 0.8‰, meeting the requirement of gauge.The data management platform is based on LabWindows/CVI, which realized many functions, such as data collecting, parameter settings of working, data uploading, curve showing, and so on. And the data fusion algorithms were implemented by using interface between LabWindows/CVI and Matlab.Finally, the principle sample application verification shows that hardware worked properly and software was a rational design. Recently, this type of electronic pressure gauge has been successfully used in Daqing oil-wells.