System Study Review of Electrical Machines under Specific Operating Conditions of Power Installations

Abstract

The problem of life cycle vulnerability, predetermined by the development stages, operation and modernization of electrical machines due tosize and weight restrictions, dynamic electromagnetic and thermal overloads, possible flooding and changes in ventilation and cooling conditionsis considered. Reducing the weight and size of electric machines implies eliminating passive sections of magnetic circuits and optimizing the ratio of copper and steel. The desire to reduce weight and size indicators and increase energy density entails increased heat generation and temperature loads of structural elements. The increase in operatingtemperatures of modern machines indicates the need to develop mathematical models that account the response of electrical materials and structural elements to the combined thermal and magnetic fieldeffects. Such models are in demand to study the temperature dependence of insulating, magnetic and operating properties of electrical machines when establishing the requiredoperating moderestrictions in order to preserve and extend the life cycle. The criterion for making management decisions aimed at changing operating modes during operation can be maximum loads that limit exceeding the maximum permissible temperatures of the electrical insulationclass used, as well as critical values of induction determined by the temperature dependence of ferromagnetproperties that affect the performance characteristics of electrical machines. Further solution to the problem lies in the creation of digital twins containing complete mathematical and computer simulation models that describe processes in electrical machines, taking into account the temperature dependence of materialphysical properties of structural elements being subjected to thermal, magnetic and electric fields.