The Intelligent Calibrator System For Multi-Channel Gas Sensor Based On FPGA

In the process of coal mine safety production, mine gas sensor plays an important role, it can real-time monitor all kinds of poisonous and harmful gas under the mine, so its reliability and sensitivity is very important. State Administration of Production Safety Supervision and Management play the perfect rules on the calibration of mine gas sensor on a regular basis. Use of mine gas sensor calibration system can effectively complete calibration of mine gas sensor on display value, response time and alarm function, ensure the safety of coal mine production.Due to the widely use of mine gas sensor, the number of sensors needed to be calibrated in the production of large and medium-sized coal mines is very large. The current calibration system can only calibrate4to8sets sensor at the same time. Sometimes adjustment for the sensor simply can not be completed within a period, it becomes a major bottleneck in coal production. According to the above problem, this paper designs a intelligent calibrator system for multi-channel gas sensor based on FPGA. This system takes C8051F020MCU and FPGA work together as the core control devices, through the communication with industrial computer to realize64units of mine gas sensor calibration tasks at the same time. The system is divided into industrial computer modules, pneumatic control modules, signal acquisition modules and infrared calibration module. The industrial computer modules are responsible for the send of calibration instructions, data collection and processing and the monitoring of calibration process. The pneumatic control module is responsible for switching of the standard gas circuit, the gas flow control and the pneumatic control of the road into64gas sensor. Signal acquisition module is responsible for collecting64gas sensor output signal as the basis of calibration. Infrared calibration module is responsible for sending Infrared calibration signal to64mines gas sensor to implement calibration tasks.In about64railways of mine gas sensor calibration at the same time, because of the limitation of the MCU I/O port and other pieces of resources, it is difficult to achieve to64railways of mines gas sensor calibration at the same time, the application of FPGA is used to extend MCU, using FPGA to realize the control of64railways of mines gas sensor gas road, the acquisition of64railways of mines gas sensor output signal and the sent of64railways of mines gas sensor infrared calibration signal, ensure the completion of tasks of the intelligent calibrator system for multi-channel gas sensorWith the debugging experiment of the intelligent calibrator system for multi-channel gas sensor, the debugging results show that the system can effectively completed64units of mine gas sensor calibration tasks at the same time, with features of high precision, high efficiency and good stability. more importantly, on large quantities of mine gas sensor calibration, the system makes the calibration speed more quickly, the set-up time more short, ensure the complet of the large and medium-sized coal mine large quantities of mine gas sensor calibration tasks, ensure the normal production of coal mine.The system use MCU and FPGA to work together, making full use of the advantage the single chip microcomputer which can work stability and control strongly,and the advantage of FPGA which is fast, flexible design, so it have very strong practicability and extensibility.