煤矿井下杂散电流产生机理及防治措施的研究

发布时间：2018-09-18 14:51

【摘要】：本课题来源于山西省晋煤集团科技攻关项目“寺河矿井下供电系统杂散电流分布及防治技术的研究”(项目编号：JMJS-JS-2012050),是针对因杂散电流而引起的井下事故频发及相关理论研究的缺乏、检测设备落后等问题而提出的。近年来,随着我国煤炭产量的持续攀升以及综采技术的快速发展,对矿井生产各环节的隐患监测及预警提出了更高要求。在我国煤矿安全事故中因杂散电流引起的爆炸及火灾事故非常多,而目前关于煤矿井下杂散电流的研究比较滞后,并没有进行系统的深层次的理论分析,且由于井下工作条件特殊,同时缺乏用于井下且检测精度高的相关检测设备。因此,研究杂散电流的产生机理,建立符合实际且准确的数学模型,开发一种矿用的杂散电流检测仪,对煤矿井下的安全生产具有非常重要的现实意义。本文确定了井下杂散电流的种类,分析了各种杂散电流的形成机理,建立了井下杂散电流的模型,通过计算仿真分析了杂散电流的分布规律,制定了检测装置的设计方案并完成硬件电路的设计,最终提出了消除井下杂散电流危害的具体措施。本文的主要内容如下：通过大量查阅文献资料并到现场进行实际调查研究,总结出了井下杂散电流的可能来源及种类,分析了各杂散电流的产生原因,总结了井下杂散电流可能带来的危害,分析了杂散电流各种危害的机理。根据井下直流杂散电流及交流杂散电流的产生机理,基于微元法建立了直流杂散电流的模型并建立了相应的计算公式,并用MATLAB分析了各参数的改变对直流杂散电流的影响；分别基于集中参数和分布参数建立了交流杂散电流的模型,在MATLAB平台下建立仿真模块,对比了在使用不.同电缆及三相对地阻抗不对称情况下交流杂散电流的变化,总结了井下杂散电流的分布规律。制定了杂散电流检测仪器的硬件设计方案,并具体绘制了各个模块的原理图,具体包括磁阻传感器的外围电路、单片机的外围电路、电平转换电路。搭建了硬件电路的测试平台,主要的测试实验有磁阻传感器输出验证实验、磁阻传感器置复位性能实验。通过仿真对比,探明了影响杂散电流的主要参数,总结了井下杂散电流的防治措施,直流杂散电流的防治措施有减小轨道电阻、减小机车负载电流、缩短供电半径等,交流杂散电流的防治措施有提高电网对地绝缘、采用屏蔽电缆及对称电缆等,为煤矿企业的生产安全提供了技术支持和保障。研究成果将大幅提高煤矿安全水平,推动煤炭行业的持续稳步发展。
[Abstract]:This subject comes from Shanxi Jinmei Group Science and Technology Project "Research on stray current Distribution and Prevention Technology of Power supply system under Sihe Mine" (Project No.: JMJS-JS-2012050). It is aimed at frequent underground accidents caused by stray current; and Lack of relevant theoretical research, Test equipment backward and so on raised by the problem. In recent years, with the continuous increase of coal output and the rapid development of fully mechanized mining technology in China, higher requirements are put forward for the monitoring and early warning of hidden dangers in every link of mine production. There are many explosion and fire accidents caused by stray current in coal mine safety accidents in our country. However, the research on stray current in coal mine is lagging behind at present, and there is no deep theoretical analysis of the system. Because of the special working conditions, there is a lack of high precision detection equipment. Therefore, it is of great practical significance to study the mechanism of stray current generation, to establish a practical and accurate mathematical model and to develop a kind of stray current detector for coal mine. In this paper, the types of underground stray current are determined, the formation mechanism of various stray currents is analyzed, the model of underground stray current is established, and the distribution law of stray current is analyzed by calculation and simulation. The design scheme of the detection device and the design of the hardware circuit are worked out. Finally, the concrete measures to eliminate the harm of underground stray current are put forward. The main contents of this paper are as follows: through a large amount of literature and field investigation, the possible sources and types of underground stray current are summarized, and the causes of each stray current are analyzed. This paper summarizes the possible harm of underground stray current, and analyzes the mechanism of various harm of stray current. According to the generation mechanism of DC stray current and AC stray current in underground, the model of DC stray current is established based on micro-element method and the corresponding calculation formula is established. The influence of the change of parameters on DC stray current is analyzed by MATLAB. The models of AC stray current are established based on the centralized and distributed parameters, and the simulation module is established on the MATLAB platform. The variation of AC stray current under the condition of asymmetry of the same cable and three relative earth impedance is summarized, and the distribution law of underground stray current is summarized. The hardware design scheme of stray current detecting instrument is established, and the schematic diagram of each module is drawn, including the peripheral circuit of magnetoresistive sensor, the peripheral circuit of single chip microcomputer and the level conversion circuit. The hardware circuit test platform is built. The main test experiments are the magnetoresistive sensor output verification experiment, the magnetoresistive sensor reset performance experiment. Through simulation and comparison, the main parameters affecting stray current are found out, and the preventive measures of underground stray current are summarized. The preventive measures of DC stray current include reducing track resistance, reducing locomotive load current, shortening power supply radius, etc. The prevention and cure measures of AC stray current include improving the insulation of power grid, adopting shielded cable and symmetrical cable, etc., which provide technical support and guarantee for the production safety of coal mine enterprise. The research results will greatly improve the level of coal mine safety and promote the sustained and steady development of the coal industry.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD608

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