基于DSP+FPGA的矿用高压电缆在线绝缘监测系统研究

矿用高压电缆的绝缘状况对煤矿高压电网的正常运行至关重要,为此设计开发了一种基于DSP+FPGA矿用高压电缆的在线绝缘监测系统,介绍其工作原理和结构组成。该系统采用多阶FIR的局部放电信号降噪方法,可通过分析矿用电缆的局部放电情况来评估电缆的绝缘状况。该系统经实验室模拟放电试验和对某煤矿配电中心的MYJV型6k V交联聚乙烯铜芯电缆进行在线监测,结果证明该监测系统可有效去除噪声干扰,并准确反应矿用电缆的绝缘状况。     

矿用高压电缆绝缘在线监测系统的研究

矿用高压电缆的绝缘状况对煤矿电网的正常运行意义重大,而局部放电（PD）信号的提取与分析是矿用高压电缆绝缘状况监测的关键所在。设计并开发了一种矿用高压电缆的在线绝缘监测系统,介绍了其工作原理和结构组成,采用了融合形态学滤波与基于Sqtwolog函数的小波阀值的PD降噪方法,通过分析矿用电缆的局部放电情况来评估电缆的绝缘状况。经实验室模拟放电试验和对平煤股份十矿配电中心的MYJV型6 kV交联聚乙烯铜芯电缆进行在线监测,结果证明监测系统可以有效去除噪声干扰,并能准确地反映矿用电缆的绝缘状况。     

基于STM32局部放电监测系统的设计研究

设计了一种针对矿用供电电缆的无线局部放电监测系统，该监测系统基于STM32介绍了相关组成电路原理图，使用高频电流传感器和信号采集电路，实现对矿用电缆的局部放电监测。最后对系统进行了节能优化处理，保证装置在电池组供电的情况下，能够长期使用。在实验室的测试表明，其精度和续航可以实现对矿用供电电缆的局部放电监测。     

高压电缆绝缘状态在线监测及诊断系统的设计

为更好地保障矿井高压电缆的安全稳定运行,通过分析矿井高压电缆的老化机理,发现伴随着电缆绝缘的老化,电缆发出的局部放电脉冲信号也会发生变化,基于此提出了可通过监测电缆局部放电脉冲信号的变化来间接判断电缆绝缘的老化程度的构想。设计了电缆绝缘在线监测系统的结构,通过应用数据采集模块来采集电缆局部放电脉冲信号,再对采集到的局部脉冲信号进行降噪处理,这些经降噪处理后的局部脉冲信号经光纤通讯网络传输至上位机,上位机进行分析处理,进而实现对高压电缆实际绝缘状态的实时监测与科学诊断,经试验测试,该监测诊断系统监测结果准确、可靠,可为高压电缆绝缘状态的判断提供技术支持。     

井下高压电缆局部放电及其传播特性研究

研究了高压电缆的局部放电与传播性能。通过构建井下高压电缆绝缘监测装置,进而现场采集电缆的局部放电信号,并对其传播性能进行了仿真分析,验证了其衰减特性。根据信号的反射特性预判绝缘下降点位置,能够达到电缆绝缘状态和预警实时监测的目的,证明了该监测装置的适用性,为相关系统研究提供了理论依据。     

脉冲电流法在矿用防爆变压器局部放电监测中的应用

局部放电在线监测已成为监测变压器绝缘系统的一种有效手段。分析了局部放电对绝缘劣化的影响,以脉冲电流法为切入点,对矿用防爆变压器的局部放电监测进行了简要论述,并说明了其在煤矿应用中的意义。     

基于双端TDR的矿用电缆故障定位系统研究

针对传统矿用高压电缆故障定位系统稳定性差、精度低的问题,介绍了一种基于双端TDR的矿用高压电缆故障定位装置。该装置以FPGA作为核心处理芯片,通过安装于电缆两端屏蔽接地线上的高频电磁传感器,感应局部放电脉冲,经FPGA处理模块反映,并通过后台管理软件,可快速判断电缆故障所在点。经实验室及现场试验分析,证明了该方法的效性与准确性。     

基于低频叠加法的矿用低压电缆在线监测研究

低频叠加法可实现对矿用低压电缆绝缘的在线监测,能够反映各种不对称故障,具有良好的故障选择性。利用电容电流补偿法对低频电流进行处理,可得到电缆的阻性电流,获取电缆绝缘电阻参数,实现对电缆绝缘水平的实时监测。     

基于电桥法的煤矿高压电缆绝缘电阻在线监测

设计了一种基于直流电桥法的矿用电缆绝缘在线监测方案,阐述了直流电桥法的检测原理,分析了检测灵敏度,讨论了在线检测精度的影响因素。通过仿真实验验证了该方法的可行性和有效性,在实验室中进行了模拟试验,试验结果表明:直流电桥法适合于井下中性点经消弧线圈接地供电系统高压电缆绝缘电阻在线监测。     

基于电桥法的煤矿高压电缆绝缘电阻在线监测

设计了一种基于直流电桥法的矿用电缆绝缘在线监测方案,阐述了直流电桥法的检测原理,分析了检测灵敏度,讨论了在线检测精度的影响因素。通过仿真实验验证了该方法的可行性和有效性,在实验室中进行了模拟试验,试验结果表明:直流电桥法适合于井下中性点经消弧线圈接地供电系统高压电缆绝缘电阻在线监测。     

基于线性预测残差分析与压扩算法的高精度局部放电定位检测方法

局部放电（PD）是导致变压器、气体绝缘全封闭组合电器、高压电缆等变电装备绝缘故障的主要原因,也是反映变电装备绝缘状态以及研判绝缘老化程度的主要依据。针对现有的超声局放监测存在的传感器灵敏度低、故障定位精度不高等问题,利用多传感器信号融合,研究了一种线性预测残差分析和压扩算法相结合的高精度PD定位检测方法,对多个传感器检测到超声局放脉冲信息之间的到达时间差做出准确估计。在此基础上,研制了一种智能超声局放传感器系统,通过源端局放超声波信号的自适应滤波和放大,提高了传感器的现场抗干扰能力和检测灵敏度。实验结果表明所提出的PD源定位方法的定位精度在1.2 cm内,验证了所提出的智能超声局放传感器的高定位精度。     

MCP强力电缆在采煤机上的应用

采煤机电缆在采煤过程中,受到各种外力作用,电缆被拉断、造成电缆故障。选用强力电缆抗拉力好,监测漏电功能灵敏。延长了电缆的使用寿命,提高使用电缆的安全性、可靠性。     

Analysis of floor failure depth by using electric profiling method in longwall gangue backfill mining

In underground mining, floor failure depth accompanying mining phases usually results from changes in the advance abutment pressure in the coal mass, and changes in stress redistribution in the areas that have already been mined. Although a variety of techniques have been applied to determine the failure depth, and a number of studies have provided the evidence for the decreasing of failure depth under backfilling, these methods and interactions have not been unequivocally identified. Based on the premise of one possible relation between the failure depth and filling body, which is that the filling materials (gangue) in the gob area can not only restrain the movement of the overlying strata effectively, but also can help to decrease failure depth of the floor in the coal mine. The failure depth in a specific longwall gangue backfilling mine was measured using the mine electricity profiling method. These electrode cables are arranged in a crossheading order to measure the depth and position of the destroyed floor using the DC method. After this, several different methods were used to interpret the recorded data from the field study for gaining failure depth, and the results were compared to the theoretical calculation values. And finally, the authors analyzed the reasons for failure depth form values recorded not indicating a large decrease trend when compared to the theoretical calculation. In this area, it is found that: ① The results using the mine electricity profiling method turns out to be robust and can be used in predicting floor failure depth, and the horizontal position of the maximum destroyed in working face of longwall backfilling. The maximum destroyed position and failure space of the floor can be identified by using this method. ② There is a time-delay processing between the advance of the working face and the failure of floor strata in the mining processing. ③ Additionally, based on the data collected from field measurements, which includes three different test electrode spacing approaches (single, double and triple electrode spacing), and the theoretical value from theoretical calculations. The premise mentioned above cannot be supported during the specific field test, and the role of the filling body in the mined area cannot decrease the floor failure depth effectively in comparison to the theory predictions. Basically, the failure depths in the two different methods have similar results and it is possible that there will not be a direct correlation between the filling body and failure depth. ④ Although the failure depth cannot decrease effectiveness when using gangue backfilling in the field testing, due to gob gangue, filling materials being able to deliver the abutment pressure from the overburden in most cases, once they were compacted and rammed by the overburden pressure, it still can make the fracture of the gob area clog and be further consolidated. In this way, it is assumed that water-bursting accidents can be prevented effectively under backfill mining. For this reason, gangue backfilling may make a significant contribution to safety mining.     

侧向支承应力作用下6.0 m小煤柱巷道加固技术研究

为了解决塔山煤矿三盘区6.0m小煤柱巷道围岩稳定性控制难题,利用数值模拟与现场实测研究相结合的方案,对8311工作面回采过程中煤柱应力的变化规律和侧向支承应力作用下小煤柱巷道加固技术进行了研究,提出了对穿锚索加固小煤柱配合顶板支护方案,有效的降低了6.0m小煤柱巷道的围岩控制技术难度.数值模拟研究表明,随工作面与测站相...     

基于单片机的煤电钻漏电保护设计

介绍了一种基于单片机的煤电钻漏电保护的设计方法。该设计可以根据电网电压的波动调整动作值,从而保证电缆绝缘电阻的动作值不变;使用软件,能可靠地实现漏电闭锁;并且可以实时显示电缆的绝缘状况,为设备的维护和维修提供可靠的依据。     

基于VRS技术的煤矿地表变形监测实践研究

随着采深的增大,晋华宫矿开采过程产生严重的地表沉降问题,对该矿地面建构及设施造成了安全隐患。该矿选择采用虚拟参考站技术(VRS技术)来对地表沉降进行测量监测。监测结果表明,VRS技术具有更好的准确性和科学性,在监测过程中表现出测量范围广、工作效率高、工作量小的特点,可以对该矿地表沉降问题进行有效监测。     

基于差分进化算法的矿震震源谱参数反演

针对地震震源谱的零频极限及拐角频率参数反演计算,本文提出采用差分进化算法,并选取四种不同差分进化策略,利用矿山地震监测系统记录的采矿诱发矿震的地震波资料及Brune位错模型,对零频极限及拐角频率进行反演。经过差分进化算法反演,并与遗传算法反演结果对比,确定差分进化算法能够实现零频极限及拐角频率的精确计算。同时,研究发现针对多元非线性Brune位错模型进行差分进化反演,其变异策略中的rand相比best,更能够实现全局寻优能力,避免陷入搜索停止,出现早熟现象。再根据反演的零频极限和拐角频率,进而计算地震矩、震源半径及视应力等震源参数,从而为研究采矿区域应力分布、集中及释放规律、判别开采作业区域安全提供了很好的途径。     

基于分布式光纤的覆岩变形特征监测试验研究

采动覆岩变形、破坏方式及其内部应力演化规律是采矿工程领域研究的重要问题,通过科学、有效的监测手段对上覆岩层在工作面开采过程中的变形及来压规律进行实时监测至关重要。将分布式光纤水平、垂直埋设在模型内部,监测覆岩变形特征与应力应变状态。结果表明,1-2煤回采过程中,水平传感光纤的"马鞍形"频移曲线反映了覆岩破断的动态变化过程;布里渊频移变化度准确实现了工作面的来压判别;分布式光纤的时空演化规律揭示了整个开采过程中相似模型的应变分布特征。     

Modeling method for measuring the admittance of insulation in a network with an isolated neutral voltage up to 1000 V in mines using Matlab/Simulink

New results that solve the important scientific task of providing electrical networks with an isolated neutral voltage up to 1000 V in mining enterprises are obtained. The method for measuring the admittance of insulation networks with isolated neutral voltages up to 1000 V, which will provide improved accuracy and speed measurement admittance network insulation, is described. The measurement is made by adjusting the additional conductance to ensure equal quantities of module phase voltage to earth and zero phase-sequence voltage. In this connection the additional conductance corresponds to the admittance of network. The simulation model of a method of measuring the admittance of insulation using the Matlab/Simulink environment is analyzed. The proposed method is simple, as the instrumentation, singlephase voltage transformers that are needed to measure the admittance of network, are in the service manual of the energy management companies.