瞬变电磁法事故井距离探测建模与仿真

Modeling and simulation of transient electromagnetic method for fault well distance detection

距离探测作为事故井探测定位中的关键环节,基于井下瞬变电磁事故井探测系统理论分析了感应电动势与两井相对距离的一一对应关系,利用Maxwell软件建立事故井电磁探测的三维模型,得到不同探测距离下事故井套管的磁场强度和分布情况,为探测仪器与事故井套管相对距离的标定和刻度提供理论依据。最后讨论了不同距离下线圈匝数和发射电压对二次磁场分布的影响,并总结其规律。结果表明,二次场信号强度均与线圈匝数和发射电压成正比。该研究结果可以为瞬变电磁探测仪器的设计和优化提供参考。

Distance detection is a key link in the detection and positioning of accident well.Based on the theory of downhole transient electromagnetic accident well detection system,the one-to-one correspondence between induced electromotive force and relative distance between two wells is analyzed.The three-dimensional model of electromagnetic detection of accident well is established by using Maxwell software,and the magnetic field intensity and distribution of casing in accident well under different detection distance are obtained,which is used as detection instrument and accident casing the calibration and calibration of the relative distance of the tubes provide a theoretical basis.Finally,the influence of coil turns and emission voltage on the distribution of secondary magnetic field at different distances is discussed,and the rules are summarized.The results show that the signal strength of the secondary field is directly proportional to the coil turns and the transmitting voltage.The research results can provide reference for the design and optimization of transient electromagnetic detection instrument.