Research And Application Of Automatic Proportioning System In Mining Standard Gas

This paper introduces a set of automatic proportioning system about mining standard gas. The system which uses the advanced automatic control distributing gas technology and uses gas flow mass flow controller for controlling the gas flow, compounding standard gases of required concentration, is a dynamic distributing gas system based on PC and the C8051F020 single-chip unit controlling technology.Starting from the actual demand of standard gases, this paper analyses and compares a series of standard gas proportioning methods and gas flow detection methods, selecting a gas automatic distribution method based on the mass flow control, establishes a mining standard gas automatic proportioning system designing scheme,which consists of proportioning system process, hardware and software system designing scheme.Hardware development. design of proportioning system includes selection of the core chip, the power supply design, single-chip unit minimum system design, circuit design of gas circuit on-off control, flow control design of mass flow controller, processing circuit design of analog signal and the anti-interference processing design of hardware circuit, etc.Software development design of proportioning system includes software design of principal computer and subordinate computer. Subordinate computer software design based on the Keil uVision4 development environment for programming design, is to compile, link and debug, completing flow control and collection, etc. According to the characteristics of the flow control, the paper introduces median filter and fuzzy PID control technology for data real-time processing, to realize accurate control of gas flow and improve the gas distribution accuracy. Based on Visual C++6.0 environment for programming design, Principal computer software design develop a friendly and intuitive man-machine interface of mining standard gas proportioning system, including welcome interface, management interface, proportioning interface, real-time data and flow curve display interface.With gas distribution comprehensive experiment, the proportioning system can normally complete process control according to the control command; compounding standard gas for many times, calibrating concentration for the compounding standard gas by the gas chromatography, analyses and test whether the standard gas concentration value meet the requirements or not.