Inversion simulation for metal pipe electromagnetic parameters based on induction measurement method

For correction of metal casing effect in induction logging technology, the casing parameters are obtained. A measure model which consists of one transmitter and two receivers is modeled in cased hole. A formulation of the inverse problem of determination of the electromagnetic parameters of metal tubes from the receiver voltage measured at single frequency is presented. The objective function is constructed based on the least square principle and a multi-parameter search algorithm using golden section search is designed. The results show that: When the true conductivity of metal casing changes from 2×106 S/m to 8×106 S/m, the true relative permeability of metal casing changes from 50 to 100 and the quality coefficient ϵ is set to 0.1%, the relative error Δσ2 of the casing conductivity can be a minimum of 0.0288% and a maximum of 0.1700%, the relative error Δμ2r of the casing relative permeability can be a minimum of 0.0144% and a maximum of 0.1861%, and the number of the optimum search is 14 or 15. © 2018 Politechnica University of Bucharest. All rights reserved.