局部通风机是井下掘进过程中的主要设备，其使用的灵活性和效能直接影响着瓦斯的安全排放。目前，我国大多数煤矿井下局部通风机调速能力较差，智能化程度较低，且多数是不调速的。在井下，局部通风机一接进电网便无控制地长期恒速运转，“一风吹”现象非常严重。这样既浪费了电能，又极易造成上隅角瓦斯聚集，形成事故隐患。针对这一问题，本文设计了一种结合模糊控制技术的局部通风机瓦斯智能排放自动调节系统。 论文首先阐述了掘进工作面局部通风机瓦斯排放的现状和存在的问题，以及本文研究的主要内容及意义。然后对局部通风理论进行了总结和概括，包括掘进巷道的通风要求及布置情况，掘进工作面通风方式和工作面风量计算，并对风机节能原理作了说明。论文对瓦斯浓度模糊控制器进行了设计，控制器以掘进巷道瓦斯浓度的偏差和偏差变化率作为输入，控制变频器的输入电压为其输出。在常规模糊控制器的基础上，设计了自调整参数、自调整因子和复合型等优化模糊控制器。采用优化模糊控制算法后，系统响应速度变快，控制性能显著改善。为减少掘进工作面上隅角瓦斯聚集，运用双模模型理论，制定了掘进工作面正常通风和瓦斯超限排放两种状态下掘进工作面迎头、掘进巷道回风流和回风巷混合风流处三点瓦斯浓度的隶属度函数，仿真得出了两种状态下各点对应瓦斯浓度范围及对应的电源频率和电机转速。论文以TMS320F2812DSP为基础，对系统软硬件进行了研究设计，包括系统主电路、控制电路和保护电路的设计。软件部分采用模块化设计思想，编制了主要模块的软件流程框图。结合变频器综合控制实验台，做了相应实验。 研究证明，本论文将模糊控制思想引入到掘进工作面瓦斯排放中，有效地提高了系统的智能化水平和安全性指标，为掘进工作面瓦斯智能排放提供了一定的方法指导。

The local fan is the main equipment in the mine driving process, whose flexibility and efficiency can directly affect the safety of gas discharge. At present, the driving motor of local fan in the most coal mine can not change its frequency intelligently, whose intellectualized degree is lower, and in the most of mine the frequency of the driving motor is invariable. In the mine well, the local fan works in the long-term constant speed as soon as it meets the electrical network, the phenomenon of invariable speed is extremely serious. It can not only waste energy but also be easy to creat the ultra density gas drainage and cause the potential accidents. Therefore, this paper designed an intelligent drainage system of gas for local fan, combining the fuzzy control algorithm. This system controls and changes the velocity of local fan in the best efficiency automatically and continuously, according to the parameters of changeable gas density, in the condition of satisfying air quantity the workers needed in the heading face. To begin with, the paper indicates the existent problems for mining local fan gas drainage in the heading face, including its actuality and development tendency, as well as the research content and significance. In addition, ventilation requirements and airflow regulation and fan energy conservation principle in coalmine are introduced detailedly among the local ventilation theory. The fuzzy controller is gained as the most important part of gas drainage system in the heading face, whose input variables are gas density error and gas density error change and output variable is the control voltage of the transducer. The self-organizing parameters fuzzy controller, self-organizing weight fuzzy controller and compound fuzzy controller are designed to compare with normal gas fuzzy controller separately by system module and theory analysis in view of the characteristics of normal gas fuzzy controller. With the most important, the membership functions of gas sensors locating on the heading face, on the upcast air and on the gaseous mixture during two states of normal ventilation and gas discharging in the heading face are formulated accurately. In the following, the gas density in different positions and the corresponding power frequency are obtained by double fuzzy control model simulation. In the end, the software and hardware of control system are discussed theoretically, with the TMS320F2812 DSP chip as its control core. The hardware part contains main circuit, control circuit and protection circuit, and the software part provides some subroutine flow charts with the introduction of modulization design concept. It enhances the intelligence and safety of the local fan gas drainage system greatly in the heading face in virtue of fuzzy control theory, which provides some method instructions for local fan gas intelligent drainage.