Development Of Intelligent Gas Detecting System

In this paper, the situation of gas detecting in our country's coal mine is introduced. Based on analyzing the capability of diversified instruments of gas detecting, both the advantages and disadvantages of the catalytic combusted instrument are pointed out, and a gas detecting system which integrated the technology of smart sensor and wireless sensor network is put forward.The smart gas sensor was developed based on the Mega48v microcontroller. The circuits of gas detecting, power supply, amplifier, preventing impact of high concentration gas, alarm, display using LED and demarcating were designed. The smart gas sensor was small in shape, reliable and has the character of plug and play, which was the good foundation for smart gas detecting system. The wireless sensor network is established by the module nRF2041, and the functions of self-diagnosis and self-correction are realized. The MCU code was written in C language, the program of real-time monitor was developed by means of virtual instrument technology, the arithmetic of average filter, nonlinear compensation and calibration of zero point and sensitive was used in the data processing, and the transducer electronic data sheet (TEDS) was designed for every sensor. The methods of demarcation and calibration was designed, it is not only improved the detecting precision and reliability, but also predigested the operation, prolonged the demarcation cycle, enhanced the maintainability and reduced maintainable cost.Based on the related national standards, we designed and completed the experimentation about stability of show value, elementary error, working hours and elementary stability, and the results proved that all the capability could satisfy the standards. Through the experimentation, the influence to the detecting capability such as voltage of power supply, flux of gas swatch, oxygen concentration of lab circumstance was analyzed, as well as the technology of anti-jamming and notice of operation was pointed out, which perfected the design of the smart gas sensor.