International Society for Industrial Process Tomography

Capacitively Coupled Impedance Imaging Based on Wideband Phase Measurement

Y. D. Jiang^1,2*, M. Soleimani¹

¹Engineering Tomography Laboratory (ETL), Department of Electronic and Electrical Engineering, University of Bath, Bath, UK

²State Key Laboratory of Industrial Control Technology, College of Control Science and Engineering, Zhejiang University, Hangzhou, China

^*Email: jiangyandan123@163.com; M.Soleimani@bath.ac.uk

ABSTRACT

Electrical impedance tomography (EIT) is an effective approach for non-intrusively reconstruct the distribution of dielectric parameters inside the region of interest. Traditional EIT works mainly focus on using the real part or imaginary part of the impedance separately for dielectric parameter imaging, few research works pay attention to the phase information of the voltage/current measurements. In this work, a contactless impedance imaging method using capacitive coupling with wideband phase information of the measurements is presented. A 12-electrode capacitively coupled EIT phantom was developed and the corresponding forward modelling was implemented by simulation based on Finite element method (FEM). An impedance analyzer was used to obtain the phase measurements within a frequency range from 200 kHz to 15 MHz. Saline and two plastic rods with different diameters were used to carry out the experiments. Image reconstruction was implemented by the classic Tikhonov regularization algorithm. Preliminary experimental results investigated the relationship between conductivity distribution and phase measurements, and also showed the potential of phase-based impedance imaging.

Keywords Electrical impedance tomography (EIT), impedance imaging, capacitive coupling, wideband phase measurements.

Industrial Application: General