【作者】 陈新军；

【导师】 刘明光；

【作者基本信息】 北京交通大学 ， 高电压与绝缘技术， 2007， 硕士

【摘要】 本文首先介绍了我国煤矿安全面临的形势和煤矿安全的意义。指出瓦斯爆炸是制约煤矿安全生产的主要灾害，是矿井事故中最严重的。目前我国煤矿瓦斯几乎全部采用热催化燃烧型的瓦斯传感器检测瓦斯。由于零点漂移和瓦斯信号输出非线性的原因，需频繁进行零点校正和灵敏度的校正，瓦斯传感器存在寿命短、稳定性差、调节周期短。随着瓦斯浓度的升高，催化元件在检测瓦斯时，呈明显的非线性特性。本文对线性度拟合和非线性拟合进行了深入的分析。通过比较和对比，采用了分段折线校正法进行非线性补偿。零位稳定是影响测量系统精度的重要因素，采用保存零位输出值来解决瓦斯传感器的校零处理。根据自动调校原理和总线技术，对传统的瓦斯检测电路和方法进行了改进。在此基础上，提出了智能瓦斯传感器检测电路总体设计方案。选用51单片机作为微处理器。在硬件设计方面主要包括电源模块的设计、模拟调理电路模块的设计、单片机模块的设计、外围芯片模块的设计、报警电路模块和通信模块等的设计。使用外部EEPROM存储器，存储瓦斯安全浓度、零点漂移系数、非线性补偿系数，实现了掉电保护功能。在芯片的选择上，大量使用具有串口的芯片代替了并口的芯片，接线比较少，单片机节省了I／O口，增强了单片机的功能。本文对各种通信技术进行了深入的探讨和分析，比较各种通信方式的优缺点，采用了RS485总线技术进行瓦斯传感器和井下分站的传输。通过RS485总线将瓦斯浓度上传给井下监控分站，实时监控瓦斯的浓度状况等。软件采用模块化程序设计方法，用C51编写代码。选用VC++作为系统上位机监控软件程序的编写。本文对每个子程序模块都进行了详细的编写，为了使流程更加直观，绘制了流程图。在完成系统的硬件和软件设计、制作后，进行了一系列模拟试验，试验结果符合要求。更多还原

【Abstract】 This paper introduces firstly situation of coal mine safety and the importance of mining. The greatest disaster in coal mine is gas disaster, and main performance of the disaster is gas explosion.Methane is analyzed by thermocatalysis sensor in Coal Mines in our country at Present. With zero drift and nonlinear in the output signals, zero adjustment and sensitivity correction system of methane sensors is needed frequently. Methane sensors always have the problems of short service life ,bad stability and short-period. The more gas concentration is,the more non-linear thermocatalysis sensors. Methane sensor’s linearity fitting and nonlinear fitting are presented. After analysis and comparison, the piecewise interpolation is used to do nonlinear data processing. Stable zero is the most important affection factor of measurement accuracy. Zero self adjustment is processed by storing zero-value.Based on auto-calibration technology of mine methane sensor and bussing technique, improvements are made in conventional measurement circuit and method of detection. Based on this,a new kind of design scheme of sensing system for thermocatalysis sensors is introduced.MCU is chosen as the microprocessor. Among them ,the control system of hardware has introduced the peripheral circuit including main chip, circuit of power supply ,module of the signal gathers ,alarm circuit and communication circuit. Gas satety concentration,zero drift and nonlinear coefficient are stored with the application of external memory EEPROM.With serial devices in place of parallel devices, we can save resources of MCU’s I/O and increase the functions of MCU. The paper makes a lot of researches on communication technology. After the research on the comparison of communication technologies, the data transmits between the sensors and underground monitoring outstations through RS485 bus. The sensor sends gas concentration to underground monitoring outstations for real time monitoring of methane.The modular programming approach is adopted on the software design and code is writed in C51 language. Software programming has been done to realize these functions of subprogram in detail. The technological flowsheets are drawn more visually.After software and hardware of system are designed, the experiments are designed. I made a series of simulated tests under the background of non-test in field. Verification test of each functional module is carried,then the whole systems do .更多还原