Factors of AC field inhomogeneity 0in impedance measurement of cylindrical conductors

Abstract

The AC and quasi-DC models of an impedance of cylindrical conductor have been developed. The influence of inhomogeneity of field inside this conductor on measurement errors is considered. Heterogeneity current densities in metals are conditioned by the skin effect and proximity effect of the return conductor. The voltage drop on thin current electrodes conditions the heterogeneity current densities in liquids. Character of change of error is identical regardless of the type of field (electromagnetic or quasi-static). The electrical model of the bulk impedance should be the parallel capacitive equivalent scheme. The ratio of the imaginary and real components of the bulk impedance determines the frequency dependence of this impedance at higher frequencies. The characteristic frequency at which impedance falls twice is determined by the electrical conductivity and dielectric permeability of conducted liquids.