Frequency adaptive conductivity measurement based on reverse approximation.

• An efficient reverse approximation frequency adaptive conductivity test circuit is realized by using full-wave rectification design. • A new frequency adaptive conductivity measurement model is proposed. • The complex problem of solving the time constant τ is avoided. • Effectively improve the detection accuracy of two-electrode conductivity equipment. Accurately measuring the solution conductivity is important both for environmental assessment and process monitoring. A reverse approximation frequency adaptive conductivity test method is proposed in this paper. This method avoids the complex calculation of the time constant τ of the first-order resistance-capacitance network and eliminates the influence of the accessory capacitance on the measurement results to the greatest extent. Through 9 groups of optimal frequency selection experiments, the optimal measurement frequency of R 1 and R x fixed ratio in a certain range is obtained. The optimal measurement frequency and dimensionless relationship model constitute a complete frequency adaptive solution conductivity measurement method.Through comparative analysis, the mean absolute percentage error of the measurement results is 2.65%, which not only improves the measurement accuracy of the existing self-developed equipment but also provides a new solution to solve the influence of additional capacitance in the conductivity measurement process. [ABSTRACT FROM AUTHOR]