A model of electrical capacitance tomography(ECT)system with configurable 48 electrodes and a strategy to combine electrodes are proposed to increase the capacitances of the current ECT system and to solve the equations of the ECT inverse problem. The strategy combines some adjacent electrodes as one electrode so that the ECT system with 48 electrodes is reconfigured as a ECT system with less electrodes
such as 8 electrodes
12 electrodes
16 electrodes or 24 electrodes. Several ECT systems with the same number of electrodes and the different rotation angles around the pipeline are obtained. Then the finite-element modeling and an image reconstruction algorithm are adopted for imaging. The model increases the number of capacitances in the equations of the ECT inverse problem
thus the ill-posedness of the equations of the ECT inverse problem caused by less equations is improved. The model also solves the problem that the capacitance value will decrease when the number of electrodes increases. Simulation results show that the proposed model and strategy can reconstruct images and improve the fidelity of reconstructed images by increasing the number of capacitances
and the error rate of images decreases by about 6% when a white noise with a standard deviation of 10% is added into the system.
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