A Picofarad Capacitance Meter Based on Phase-Sensitive Demodulation for Tomography Application

https://doi.org/10.22146/juliet.v4i2.89134

Rocky Alfanz(1), Hamzah Hamzah(2), Teguh Firmansyah(3), Irma Saraswati(4), Ceri Ahendyarti(5), Rohmadi Rohmadi(6), Imamul Muttakin(7*)

(1) Universitas Sultan Ageng Tirtayasa
(2) Universitas Sultan Ageng Tirtayasa
(3) Universitas Sultan Ageng Tirtayasa
(4) Universitas Sultan Ageng Tirtayasa
(5) Universitas Sultan Ageng Tirtayasa
(6) Universitas Wiralodra
(7) Universitas Sultan Ageng Tirtayasa
(*) Corresponding Author

Abstract


Electrical capacitance volume tomography (ECVT) is an imaging technique based on the object’s capacitance value. To provide a representative image of the object under study, the ECVT system requires a method that can measure the capacitance value in the order of picofarads (pF). This level of resolution poses a difficulty for typical commercial capacitance measuring devices, hence raising the need for a specialized method with dedicated signal conditioning circuitry. The capacitance meter based on phase-sensitive demodulation (PSD) is made to solve the aforementioned issue and it is then compared with the characteristics of a capacitance meter-based commercial Arduino setup. The designed PSD-based capacitance measuring device has 97.894% accuracy, precision of 0.704 pF, sensitivity of 0.1197 V/pF, linearity with a coefficient of determination 0.9983, and stability of 0.028 pF/min. In comparison, the capacitance meter based on Arduino has 97.943% accuracy, precision of 0.027 pF, linearity with a coefficient of determination 0.9999, and stability of 0.04 pF/min. Testing is done on an 8-electrode ECVT sensor using dielectric materials of air and water. The nearest electrode pair on the condition of air as the dielectric medium has a capacitance value of 2.62218 pF for PSD-based measuring devices and 3.4027 pF for Arduino-based measuring devices, while the pair of electrodes on the condition of water as a dielectric medium has a capacitance value 9.8229 pF for measuring device based on PSD and 9.1069 pF for Arduino-based measuring devices. The opposite and farthest electrode pair on the condition of air as a dielectric medium has a capacitance value of 0 pF for PSD-based measuring devices and 0,0798pF for Arduino-based measuring devices, while the pair of electrodes on the condition of water as a dielectric medium has a capacitance value of 4.652 pF for PSD-based measuring devices and 0.1224 pF for Arduino-based measuring devices.

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References

W. Warsito, Q. Marashdeh, and L.-S. Fan, “Electrical Capacitance Volume Tomography,” IEEE Sensors J., vol. 7, no. 4, pp. 525–535, Apr. 2007, doi: 10.1109/JSEN.2007.891952.

W. Q. Yang, “Hardware design of electrical capacitance tomography systems,” Meas. Sci. Technol., vol. 7, no. 3, pp. 225–232, Mar. 1996, doi: 10.1088/0957-0233/7/3/003.

S. V. Balakin and D. L. Serbinov, “A Method of Determining the Level of Dielectric Liquids from the Parameters of a Model of a Capacitance Fuel Level Sensor,” Meas Tech, vol. 60, no. 10, pp. 998–1002, Jan. 2018, doi: 10.1007/s11018-018-1307-7.

H.-Y. Yang, Y. Chen, and H. Zhao, “Signal acquisition and processing method for capacitive electromagnetic flowmeter,” Journal of Electronic Science and Technology, vol. 19, no. 1, p. 100026, Mar. 2021, doi: 10.1016/j.jnlest.2020.100026.

K. Kishore and S. A. Akbar, "Evolution of Lock-In Amplifier as Portable Sensor Interface Platform: A Review," in IEEE Sensors Journal, vol. 20, no. 18, pp. 10345-10354, 15 Sept.15, 2020, doi: 10.1109/JSEN.2020.2993309.

J. Kryszyn, W. T. Smolik, B. Radzik, T. Olszewski, and R. Szabatin, “Switchless charge-discharge circuit for electrical capacitance tomography,” Meas. Sci. Technol., vol. 25, no. 11, p. 115009, Nov. 2014, doi: 10.1088/0957-0233/25/11/115009.

W. Q. Yang and T. A. York, “New AC-based capacitance tomography system,” IEE Proceedings - Science, Measurement and Technology, vol. 146, no. 1, pp. 47–53, Jan. 1999, doi: 10.1049/ip-smt:19990008.

F. T. Kühn and P. A. V. Halderen, “Design of an active-differentiator-based capacitance transducer for electrical capacitance tomography,” Meas. Sci. Technol., vol. 8, no. 8, pp. 947–950, Aug. 1997, doi: 10.1088/0957-0233/8/8/020.

I. Muttakin, A. Yusuf, R. Rohmadi, W. Widada, and W. P. Taruno, “Design and Simulation of Quadrature Phase Detection in Electrical Capacitance Volume Tomography,” TELKOMNIKA, vol. 13, no. 1, p. 55, Mar. 2015, doi: 10.12928/telkomnika.v13i1.1299..

S. Malik, L. Somappa, M. Ahmad, T. Islam, and M. S. Baghini, “An accurate digital converter for lossy capacitive sensors,” Sensors and Actuators A: Physical, vol. 331, p. 112958, Nov. 2021, doi: 10.1016/j.sna.2021.112958.

M. Varga, M. Romakov, N. Blaz, and M. Damnjanovic, “Measurement of capacitive sensor with Arduino,” in 2016 39th International Spring Seminar on Electronics Technology (ISSE), Pilsen, Czech Republic: IEEE, May 2016, pp. 490–493. doi: 10.1109/ISSE.2016.7563247.

M. Liao, Y. Tian, and K. Wang, “Micro-capacitance Measurement Based on Phase-Sensitive Detection,” in 2010 Third International Symposium on Information Science and Engineering, Dec. 2010, pp. 375–378. doi: 10.1109/ISISE.2010.42.

J. C. Lotters, W. Olthuis, P. H. Veltink and P. Bergveld, "A sensitive differential capacitance to voltage converter for sensor applications," in IEEE Transactions on Instrumentation and Measurement, vol. 48, no. 1, pp. 89-96, Feb. 1999, doi: 10.1109/19.755066.

R. Fahrizal, J. S. Julianto, A. Maulana, R. Alfanz, C. Ahendyarti, Rohmadi and I. Muttakin, “Electrical Tomography Sensor Modelling for Detection of Fuel Proportion in Vessel,” Jurnal Ilmiah Teknik Elektro Komputer dan Informatika (JITEKI), vol. 9, no. 2, pp. 493–501, Jun. 2023, doi: 10.26555/jiteki.v9i2.26304.



DOI: https://doi.org/10.22146/juliet.v4i2.89134

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SINTA 4 accredited based on Decree of the Minister of Research, Technology and Higher Education, Republic of Indonesia Number 225/E/KPT/2022, Vol. 2 No. 1 (2020) - Vol. 6 No. 1 (2025)

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