TY - GEN
T1 - DC bias compensation in digital AC-based capacitance measurement for ECT
AU - Zhou, Haili
AU - Xu, Lijun
AU - Cao, Zhang
AU - Hu, Jinhai
AU - Liu, Xingbin
PY - 2011
Y1 - 2011
N2 - The AC-based capacitance measuring circuits are widely used in electrical capacitance tomography. In the circuit, the desired exciting and measuring signals are alternative current (AC) ones that should have a zero direct current (DC) component. However, because of the non-deal characteristics of the operational amplifiers and other electronic components, DC biases, i.e., nonzero DC components always exist in actual AC signals. The DC biases have negative influences on capacitance measurement. In the paper, theoretical analysis was carried out and a method of compensating the effect of the DC bias was introduced. A digital AC-based capacitance measuring system was constructed to implement the compensation method. Experimental results show that the signal-to-noise ratio of the system is improved by employing the proposed method.
AB - The AC-based capacitance measuring circuits are widely used in electrical capacitance tomography. In the circuit, the desired exciting and measuring signals are alternative current (AC) ones that should have a zero direct current (DC) component. However, because of the non-deal characteristics of the operational amplifiers and other electronic components, DC biases, i.e., nonzero DC components always exist in actual AC signals. The DC biases have negative influences on capacitance measurement. In the paper, theoretical analysis was carried out and a method of compensating the effect of the DC bias was introduced. A digital AC-based capacitance measuring system was constructed to implement the compensation method. Experimental results show that the signal-to-noise ratio of the system is improved by employing the proposed method.
KW - demodulation
KW - digital system
KW - electrical capacitance tomography
KW - nonzero DC component
UR - https://www.scopus.com/pages/publications/80052139731
U2 - 10.1109/IST.2011.5962194
DO - 10.1109/IST.2011.5962194
M3 - 会议稿件
AN - SCOPUS:80052139731
SN - 9781612848969
T3 - 2011 IEEE International Conference on Imaging Systems and Techniques, IST 2011 - Proceedings
SP - 79
EP - 82
BT - 2011 IEEE International Conference on Imaging Systems and Techniques, IST 2011 - Proceedings
T2 - 2011 IEEE International Conference on Imaging Systems and Techniques, IST 2011
Y2 - 17 May 2011 through 18 May 2011
ER -