Algorithm for recalculation of temperature of asynchronous motor based on equivalent thermal circuit

Abstract

Diagnostics of electrical equipment at industrial enterprises is an urgent task, since the failure of the main and auxiliary electric drives can lead to significant economic losses for the enterprise. The main share of failures of asynchronous motors is caused by their overload and, accordingly, overheating of the stator winding. Such overheating leads either to an interturn circuit and engine failure, or to a significant reduction in its resource. Therefore, winding temperature control is an important task. In this paper, we propose an algorithm for calculating the temperature of an induction motor with a squirrel-cage rotor with a changing load on the shaft using an equivalent thermal circuit consisting of 10 main nodes. In the work, methods of mathematical modeling were applied using previously developed software, as well as Excel. The task was set to check the possibility of using an equivalent thermal circuit for dynamic modes of operation of electrical equipment. The results of the work allow us to conclude that the developed algorithm can be used for further modeling of both stationary and non-stationary thermal models of asynchronous motors with a squirrel-cage rotor.