煤体复电阻率实验室测试方法研究

实验室煤体复电阻率测试旨在提供可靠的复电阻率数据，为进一步现场应用基础研究。影响煤体复电阻率测量精度的因素众多，其中电极板为最重要的因素之一，极板的厚度和大小都会对煤体复电阻率测量产生影响，因此电极板的变化对测量参数的准确性有重要意义。通过选用导电性较好的紫铜材料作为极板，对3种不同厚度的极板材料进行了复电阻率测量，分析极板厚度对激发极化效应的影响，测试了直径为1,2,3,4,5 cm 5种大小极板对煤体复电阻测量的影响，并使用Cole-Cole模型进行数据拟合。得出结论如下：1)极板本身的极化效应和极板与煤样端面贴合程度是影响煤样复电阻测量误差的主要因素，3种不同厚度的极板材料中导电铜纸误差最小；2)对同一个煤样而言极板面积变化仅对复电阻率幅值有较大影响，对煤样激发极化的影响可以忽略。

Experimental study on complex resistivity test of coal

The purpose of complex resistivity measurement of coal in laboratory is to provide reliable data of complex resistivity for further field application. The measurement accuracy of coal complex resistivity is affected by many factors, and electrode plate is one of the most important factors. The thickness and the size of electrode plate will affect the result of coal complex resistivity measurement, so the change of electrode plate is of great significance to the accuracy of measurement parameters. In this paper, the complex resistivity of the electrode material with three different thicknesses is measured by using the copper material with better conductivity as the electrode plate. The influence of the thickness of electrode plate on the induced polarization effect is analyzed. The influence of different sizes of electrode plates(diameter of 1 cm, 2 cm, 3 cm, 4 cm and 5 cm) on the measurement of the complex resistivity of coal is tested, and the Cole-Cole model is used for data fitting. The results show that 1) the polarization effect of the electrode plate itself and the bonding degree between the electrode plate and the end face of the coal sample are the main factors affecting the measurement error of the complex resistivity of the coal sample, and the error of the conductive copper paper is the smallest among the three electrode materials. 2) For the same coal sample, the change of the area of the electrode plate only has a great influence on the amplitude of the complex resistivity, and the influence of the area on the induced polarization of the coal sample can be ignored.