煤巷聚焦多点电源探测电场超前扫描控制策略

Detection electric field control strategy for advanced scanning detection of focusing multipoint current sources in coal mine roadway

为实现煤巷聚焦多点电源有效探测电场聚焦深度扫描和偏转角度扫描,准确把握有效探测电场的变化规律,根据超前扫描探测机理,利用高斯定理,采用两种不同的方法对积分过程进行求解,推导单根有限长均匀带电直线电极的电场线方程。利用电场线空间分布的对称性,归纳推理共面多电极电场线方程。改变聚焦屏流比系数,计算有效探测电场线边界线方程,分析平均电流密度及空间立体角变化规律;同时改变聚焦屏流比系数和偏转屏流比系数,分析电场边界线下边界角及偏转角变化规律,确定出超前扫描探测主电极与约束电极发射电流取值范围。此研究为野外开展聚焦多点电源电法勘探提供技术指导,对完善聚焦电法勘探机理,推动该技术理论发展具有重要意义。

In order to realize the effective detection of electric field focusing depth and deflection angle scanning of focusing multipoint current sources in coal mine roadway,and accurately grasp its variation,according to the ad-vanced scanning detection mechanism,Gauss theorem and two different methods were used to solve the integration process and derive the electric field line equation of a uniformly charged linear electrode with finite length.The electric field line equation of coplanar multi-electrode layout is induced and deduced through using its spatial dis-tribution symmetry.By changing focusing shielding current ratio coefficient,this paper calculates the boundary line equation of effective detection electric field lines and analyzed the variation of average current density and spatial angle.The lower boundary angle and the deflection angle variations of the electric field boundary line were ana-lyzed through changing simultaneously focusing and deflection shielding current ratio coefficients.The range of emission current intensity of the main electrode and the constrained electrode for advanced scanning detection was determined.This research will provide a technical guidance for the electric survey of focusing multipoint current sources in the field,and is of great significance for improving the exploration mechanism of focusing electric method and promoting the development of geophysical theory.