Abstract

The measurement circuit of electrical capacitance tomography (ECT) system mainly includes CMOS switches, C/V conversion circuit and Data processing circuit. In order to improve the image reconstruction quality, conversion circuit is very necessary to the small capacitance measurement circuit. A charge/discharge measurement circuit is one of the most suitable for the C/V conversion circuit in ECT. The stray capacitance between the measurement electrodes and earth can be large and have an effect on the capacitance measurement. This paper analyzes this effect, taking into account the ON-resistance of the COMS switch, the unit gain frequency of op-amp, and gain error in the measurement circuit. Finally, it is shown that if the range of stray capacitance is 150±60pF, overall error would be estimated. Comparing the effects of the circuit parameters, this charge/discharge-based capacitance is effectively stray-immune. It is a more efficient analysis to C/V circuit in ECT and offers a great benefit to information processing.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.