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Purpose. To present a comprehensive analysis of domestic and foreign experience regarding the existing optimization tech niques in the problems of the power losses minimization in electromechanical systems with an induction machine for reduction of the total electricity consumed from the grid.Methodology. A detailed study of the developments in the field of efficiency optimization of threephase induction machines through optimal control and design techniques has been done. Special attention is given to vectorcontrolled systems. Sustainable development of a few trends was traced in this domain. The reference value of the fieldgenerating current is an additional degree of freedom in the mathematical model of the investigated system. It influences the magnetic flux linkage dynamics and mechanical torque equations. Hence, the implemented model allows for a comparative analysis of different approaches to ensure minimum energy consumption with an adequate intensity of transients.findings. Among numerous control techniques, simple state control, loss modelbased control and search control efficiency optimization algorithms have been highlighted. The simulation example on efficiency optimization of an asynchronous machine was performed in the framework of an indirect fieldoriented control system considering the stepped trajectory of load torque, which is possible as a result of mechanical perturbation or when the motor performs complex speed profiles or counteracts shock loads.originality. The rigorous review indicates that existing optimization algorithms in conventional still can be used for induction motor drive applications. However, some existing problems in achieving the best control were not summarized. Accordingly, for the first time, this review provides suggestions for the future research and development of dynamic energyefficient control in in duction motors.Practical value. The threephase induction motor drives are a nonlinear system that is tough to describe precisely theoretically due to their sudden changes in conditions of operation mode and parameter variation. Thus, advanced algorithms are needed to enhance their performance in addition to effective hardware solutions. The suggested alternative solution will hopefully lead to increased efforts toward the development of advanced control systems for future applications.

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The current paper discusses the adaptive choice of a filter time constant for filtering the steady-state flux reference in the energy-efficient control problem of field-orientation induction machines in transient behavior when load and speed conditions are changing taking into account the effect of the main induction saturation. It is shown that by appropriately managing the flux linkage rate of change the energy losses per full operation cycle under torque changes can be significantly reduced compared to the conventional cases. The analysis for the appropriate choice of the filter time constant as a fraction of the rotor time constant is based on a numerical study and simulation results for three different induction machines with different rated powers.

Аналізуються актуальні питання організації навчання іноземних студентів у Національному технічному університеті «Дніпровська політехніка». Розглянуто інтенсифікацію розвитку контактів між країнами, розвиток освітніх програм англійською мовою та адаптивна спроможність іноземних студентів. Висвітлено фактори, що впливають на ефективність процесу мовної підготовки до навчання за обраними спеціальностями в умовах дистанційної освіти.