Порівняльний аналіз точності моделей струму комутації, які враховують наявність короткозамкнених витків обмотки якоря

Abstract

UA: Розглянуто існуючі математичні моделі часової залежності струму комутації колекторного електродвигуна. Моделі класифіковано за підходами, використаними при описанні комутованого кола секції обмотки якоря. Визначено явні та неявні математичні й фізичні припущення, прийняті при побудові цих моделей. Дано оцінку ступеню прийнятності кожної з моделей з погляду точності відтворення реальної часової залежності струму комутації.

EN: A modern strategy for locomotive maintenance is based on the operational diagnostics of their equipment. Currently, a large number of locomotives are equipped with DC electric motors. These locomotives will be operated in the short term. About half of the failures of DC electric motors are caused by the failure of the armature structure elements and, above all, the armature winding. Detection of the nature of damage to this winding and the extent of its damage reduces the time spent on repairing the motor. The large fleet of locomotives with DC commutator motors determines the relevance of the problem of diagnosing the armature winding. The greatest amount of information about the state of the winding contains the dependence of the commutation current of its sections on time. Existing publications have paid great attention to the development of competing or complementary models of such dependencies. However, solving the problem of quantitative comparison of the developed models still requires significant efforts. The object of the paper study is the error of modeling of commutation current, provided that some of the armature winding turns are short-circuited. The aim of the study is a comparative analysis of the existing models of this current. In order to achieve this goal, the tasks were solved, as follows: 1) to clearly distinguish between models, according to methods for determining the dependence of current on time; 2) to determine the degree of physical and mathematical correctness of each of these models; 3) to assess the conditions of existence and numerical values of the differences between these models. Comparison of models in terms of accuracy has shown that the best is the selection of a separate current model for each specific combination of two special parameters. These parameters describe the degree of shorting of the armature winding section. However, it is inconvenient that with different combinations of parameters, one has to operate with different mathematical expressions. The generalized model of commutation current gives the same expressions for all combinations of the specified parameters. However, this model should be enhanced to improve its accuracy in the field of large numerical values of parameters.