Approximation of the Short-Circuit Current Based on the Secondary Current Oscillogram

Abstract

Experimental data requires mandatory processing. For example, the processing of oscilloscopes of short-circuit currents and similar processes in technology, such as thermal ones, is considered [1]. The purpose of this processing is to increase accuracy by taking into account the errors during the experiment. The problem is proposed to be solved using an approximating expression. To solve the problem, a mathematical expression from the theory of electromagnetic transient processes in energy systems is used. To solve this problem, it is proposed to use approximation of these data, and to use a widely used formula from the course on electromagnetic transients as an approximating expression. The paper analyzes various methods of function approximation: the least squares method, extrapolation, polynomial approximation, rational approximation, spline approximation, and wavelet-based approximation. As a result, a program has been developed for calculating the optimal values of the coefficients of the short-circuit current function. The program calculates and displays the optimal coefficients of the function and the coefficients of the approximation accuracy criterion. If necessary, you can plot the functions for each calculation method.