Multiple-electrodes excitation method for electrical capacitance tomography system

Aiming at the non-uniformity problem of sensitivity distribution caused by the soft field effect of the static electric field in the measurement region of capacitance sensor, on the basis of deeply analyzing the capacitance measuring principle in electrical capacitance tomography system, a triple-electrode-excitation and double-electrode-examine method is proposed. By using the new method, a more uniform electric field can be got, and the independent measurement data is also increased, which improves the ill-posed of the problems, enhances the uniformity of capacitance sensitivity. The electromagnetic properties of the sensor are simulated by utilizing the ANSYS and Matlab software. The experiment and calculation results show that the difficulty of measurement circuit is reduced. The uniformity of capacitance sensitivity is improved greatly with triple electrodes excitation and double electrodes examine method compared to singe electrode excitation method, and the quality of the reconstructed image is also improved.