A Numerical Method For Approximating The Time Constant Of A Measuring Circuit When Differentiating The Newton Interpolation Polynomial

Determination of the time constant of the measuring circuit is the main metrological task when measuring the electric capacitance at a constant current. It has been established that the most promising direction for increasing the accuracy of processing systems for measuring signals of capacitive sensors is the use of instantaneous stress values during the developing transition process. We have proposed two new algorithms for estimating the time constant, based on the approximation of derivatives using finite differences in numerical differentiation algorithms. The proposed algorithms allowed to reduce the measurement error of the electrical capacity to 0.055%.