Purpose. In the existing methods for calculating induction motors, such parameters as the coefficient of flattening of the of the airgap field curve, the differential scattering coefficient and the saturated values of the inductive scattering resistances are calcu lated according to empirical formulas, the calculated values of which differ significantly from the experimental ones. The aim of the article is to develop methods (based on field calculations) which take into account eccentricity, saturation, and higher harmon ics and is necessary when designing asynchronous motors. Methodology. By expanding the Fourier series of the magnetic induction distribution curve in the air gap of a saturated squir relcage induction motor obtained by calculating the field by the finite element method, higher harmonics are determined taking into account the saturation and the rotor axis eccentricity relative to the stator axis and the exact values of inductive resistances. findings. A technique has been developed that increases the accuracy of the calculation of an induction motor, which elimi nates errors from empirical formulas and takes into account eccentricity, saturated values of differential and groove scattering, saturation harmonics, and a flattening of the field curve in the gap, and ultimately improves the energy performance of induction motors. originality. The proposed technique for improving the calculation of induction motors in starting conditions allows determin ing the values of starting currents and torques on the motor shaft, which differ from the experimental ones by no more than the measurement error. The research results create the prerequisites for the development of an improved methodology for calculating an induction motor in all modes of its operation, which will allow us to design highly efficient motors that meet world require ments. Practical value. Application of the proposed methodology for calculating the parameters of induction motors can increase the efficiency of electromagnetic calculations, reduce design errors, and reduce additional costs in the manufacture of prototypes.

Nowadays, it becomes important to solve the problem of improving mathematical models of AC electric machines in order to clarify the analytical description of transients taking into account the active resistance in the stator winding. The use of frequency characteristics will improve the accuracy of determining the design parameters of induction motors at the design stage. In this case, taking into account the active resistance of the stator winding makes it possible to determine with sufficient accuracy the characteristics of the engine in the starting modes.

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Annotation. The article represents the authors' vision on the prospects of development of automation tools, which are used on power lines. Currently available automation elements of power lines such as various monitoring systems, control devices are overviewed. It is noted about the need for integration of such elements installed on certain power line into one system. It gives the reason for introducing the concept of Line Automation System (LAS), which can be considered as one of the elements of electric power system automation and also as a component of the future Smart Grid. Some scientific studies call lines equipped with such systems as Smart Power Lines. The structural scheme of LAS is proposed and the groups of LAS sensors are described. The general requirements for LASs and their functionalities were formulated. LASs implementing prospects and their key technologies are discussed.