交流电测井中把发射线圈看作磁偶极子所引起误差的讨论

A Discussion Errors Caused by Treating Transmitter Coil as Point Magnetic Dipole in A. C. Electric Logging

给出了均匀介质中单发单收双线圈感应电动势的严格解和近似解（即把发射线圈近似地看作磁偶极子时的解）的推导过程及其表示式．以一种简单的介电测井为例，计算了这种近似给幅度比与相位差所带来的相对误差．针对其它常规交流电测井仪器进行类似的考察，可以知道对于常规测井仪器，这种误差可以忽略．

This paper presents the deducing procedures and formulations of rigorous solutions and approximate solutions (i. e. when taking transmitter coil as point magnetic dipole) of induction voltage of dual coil in homogeneous medium. Relative errors of amplitude ratio and phase shift caused by the approximation are calculated by taking a simple radio-frequency logging tool as an example. Other conventional A.C. (alternatingcurrent) logging tools are studied with the same method.Study results show that, as to conventional logging tools,this kind of errors can be ignored.