ANALYSIS AND DATA PROCESSING SYSTEMS

Abstract
In this paper, some new approaches are proposed to get parameter estimations of objects, specifically, an electrode process with a slow discharge stage (an electron transition through the electrode edge energy barrier is hindered) and a diffusion stage (delivery of potential-determining products of an electrochemical reaction to the electrode edge is slow) with this process being simulated by the Ershler-Rendlse equivalent circuit as well as to get capacitor absorption parameters by their impedance-frequency characteristics. An estimation of the electrolyte resistance Re could be obtained by averaging real part values of the total impedance measured in a high frequency range. An estimation of the double layer capacitance Cd is determined as a mean value of the ratio between an imaginary part of the electrode edge admittance and a circular frequency for an upper frequency range. Estimations of the Warburg constant Aand the charge transfer resistance Rp are made by real and imaginary parts of the Faraday impedance estimation obtained by compensating electrolyte resistance and double layer capacitance in the total impedance of the object under study. The process of measuring required object parameters was simulated under conditions of noise presence in impact and response signals with a uniform amplitude distribution in the 0-1% range of a useful signal and phase distribution in the

0-2π range. To obtain more accurate parameter estimations, the required parameters obtained as mean estimation values in ten different experiments and parameters estimations obtained in ten experiments from the research object averaged total impedance were used. The obtained estimate of the electrolyte resistance Rewas used for the model experiment of the electrolyte resistance compensation (IR-compensation). After that estimations of the double layer capacitance Cd, the Warburg constant A and the charge transfer resistance Rpwere obtained. Similar modeling was performed to find absorption parameters of the capacitor, with noise in impact and responsesignals being not taken into account.  Applying these procedures leads to improving estimation accuracy of research object parameters by an order or more. This makes it possible to increase the reliability of information about research object features.

 

References
1. Grafov B.M., Ukshe E.A.Eliektrohimichieskietsepiperemennogotoka [Electrochemical circuits of alternate current]. Moscow, Nauka Publ., 1973.128 p.

2. Leikis D.I. Ob interpretatsiirezul'tatovizmereniyaimpedansa v elektrokhimicheskikhissledo-vaniyakh [About result interpretation of measurement impedance in electrochemical research].Elektrokhimiya – Electrochemistry, 1965, vol. 1, no. 4, pp. 472–476.

3. Barker Dzh.K. [Aperiodic equivalent electrical circuited for Faraday impedance]. Osnovnyevoprosysovremennoiteoreticheskoielektrokhimii.Trudy 14 SoveshchaniyaMezhdunarodnogokomitetapoelektrokhimicheskoitermodinamikeikinetike [Main questions of modern theoretical electrochemistry.Abstracts of 14th meeting International committee of electrochemical thermodynamics and kinetics]. Moscow, 1965, pp. 42–90.

4. Novitskiy S.P.Sposobrazdel'nogoizmereniyaparametrovelektrodnoigranitsyprizamedlennoistadiirazryada [Method of separate measurement of parameters of an electrode edge for slow discharge stage]. Inventor'sCertificateUSSR, no. 1779985, 1992.

5. Novitskiy S.P.Sposobrazdel'nogoizmereniyaparametrovelektrodnoigranitsyprizamedlennoistadiidiffuzii [Method of separate measurement of parameters of an electrode edge for slow suffusion stage]. Inventor's CertificateUSSR, no. 1817011, 1993.

6. Schon G., Weisbeck W., Lorenz W.J. High-frequency impedance spectroscopy of fast electrode reactions.Journal Electroanalytical Chemistry, 1987, vol. 229, no. 1/2, pp. 407–421.

7. Sluyters J.H. On the impedance of galvanic sells. I. Theory.Recueil des TravauxChimiques des Pays-Bas, l960,vol.79, no. 9/10, pp. 1092–1100.doi: 10.1002/recl.19600791013

8. Sluyters J.H., Oomen J.J.C. On the impedance of galvanic sells. II. Experimental verification. Recueil des TravauxChimiques des Pays-Bas, 1960, vol. 79, no. 9/10, pp. 1101–1110.

9. Stoynov Z., Savova-Stoynov B. Spectral impedance analysis of electrochemical system. International society of electrochemistry, 37th meeting, Vilnius, USSR: extended abstracts. Vilnius,

24–31 August 1986, vol. 3, pp. 332–333.

10. Uksche E.A., Bukun N.G., Frumkin A.N. Investigation of the electric double layer in salts melts. ElectrochimicaActa, 1964, vol. 9, no. 1, pp. 31–44.

11. Warburg E. Uber das Verhalten sogenannter unpolarisirbarerelektroden gegen wechselstrom. Annalen der Physik und Chemie, 1899, vol. 67, pp. 493–499.

12. Whitehouse D.R. Analysis and interpretation of the interfacial impedance in adsorption kinetics.Journal of Electroanalytical Chemistry, 1971, vol.32, no. 2, pp. 265–270.

13. Pilla A.A. A transient Impedance technique for the study of electrode kinetics.Journal of the Electrochemical Society, 1970, vol. 117, no. 4, pp. 467–477.

14. Rybalka K.V., Etman M. Application of the operational impedance method to investigation of the electrochemical behaviour of lead in sulphuric acid.Journal of Electroanalytical Chemistry, 1983,vol. 148, no. 1,pp. 73–78.

15. Epshtein S.L. Skhemydlyaopredeleniyakoeffitsientaabsorbtsiikondensatorov[Schemes for determination of capacity absorption factor]. Elektronnayatekhnika.Seriya 8, Radiodetali– Electronic technique.Series 8.Radiodevices, 1967, no. 1, pp. 107–112.

16. Novitskiy S.P., Matasov A.G., Pechnikov A.L., Filatov A.V. Izmeritel' parametrovelektrokhimicheskikhob"ektov[Meterofelectrochemicalobjectsparameters]. PatentRF, no. 2204839, 2003.

17. AzarovYu.K., Dubrovin E.D.Ustroistvodlyapolucheniyaelektroskopicheskoiinformatsii o biologicheskikhob"ektakh[Device for obtain electrochemical information about biological objects]. Radioelektronnyepriborydlyabiologicheskikhimeditsinskikhissledovanii[Radiotechnical devices for biological and medical researches]. Moscow, NaukaPubl., 1966.96 p.