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The concept of merging the roles of producers of online courses is considered. It is relevant if it is necessary to quickly develop online training courses on electric drive or when converting a full-time training course into a hybrid format. The economic and technological aspects of the proposed approach are considered. Authors' capture of all the roles required to produce online courses can reduce costs and, in some cases, even improve product quality. To capture all the functions necessary for production, authors must master the technologies of capturing video from a computer screen, editing video, recording sound, editing audio tracks. To study modern electromechanical systems and electric drive control systems, knowledge of electrical machines, power electronics and control theory is required. When preparing online courses on electric drive, it is imperative to include practical exercises that are implemented using the Simulink or SimInTech visual modeling environments.

mathematical model of a wind turbine is investigated, which includes mathematical descriptions of a horizontal axis small- scale power wind turbine with permanent magnet synchronous generator with vector control and a three-phase rectifier connected to a stand-alone voltage source inverter. The maximum power point tracking of the wind turbine, which calculates the optimal rotation turbine speed for each wind speed is used. Vector control system provides the calculated optimal rotation turbine speed. The mechanical losses in the gearbox and in the synchronous machine are determined, as the iron losses and copper losses in the permanent magnet synchronous machine and commutation losses (switching and conduction losses) in stand- alone voltage source inverter are taken into account.

Analysis of the interaction of the electromagnetic field and matter is a topical area of research in modern physics. The goal of this paper is to move from mathematical postulates and formalisms of quantum mechanics to equations that include macroscopic variables. In this case, the macroscopic observables are determined by the mean values of the operator corresponding to the observable value, and the mean value is deter-mined by the density matrix. Then the equations are written only through the mean values, by substituting equivalent expressions for the density matrix. As a result, we come to a system of equations expressed in terms of such macroscopic variables as polarization and electromagnetic field. In the semi-classical approach, when the electromagnetic field is not quantized, it is necessary to add the Maxwell's equations of the electromagnetic field to the equations for the mean values. This forms a self-consistent system of equations.

Vector control of an induction motor with torque control function eliminates the need for a torque sensor, which reduces the cost of the system and simplifies the design of the electromechanical part of the load stand. This approach is applicable to study the characteristics of a BLDC machine operating in both motor and generator modes. A mathematical model of a BLDC machine, loaded by an induction motor fed by frequency converter is built in the SimInTech dynamic modeling environment. Speed-torque curve of BLDC machine is obtained. Comparison of the values of the characteristic points with the motor specification data proves the correctness of the mathematical model and the adequacy of the results.

The article analyses the essence of Smart technologies in the context of educational mobility and mobile education. Examples of elements implementation of Smart-cities concepts in China, England, Czech Republic, Finland, Great Britain and Denmark are presented. Smart-technology structure components are revealed. The research has practical value - it allows using the revealed essence and separate elements of Smart-technology structure for realization of particular models in open education system of new generation.

Based on the method of secondary sources, a mathematical model of the magnetic field of electric machines with permanent magnets is developed. As a secondary source, a double layer of magnetic charges is considered. A method is proposed that makes it possible to more accurately take into account the boundary conditions for field vectors from a double layer of magnetic charges. The main characteristics of a machine with a concentrated winding and a machine with a distributed winding are compared.

A mathematical model of a small power wind turbine with a horizontal axis is considered. The law of control is investigated, that maximizes the output (generated) power when changing wind speed (Maximum Power Point Tracking). Investigations of the output, aerodynamic, and mechanical characteristics of a wind turbine were carried out. Considered the Tip speed ratio for MPPT method. The proposed mathematical model is used to determine the optimal tip speed ratio value for the output power.

A method is proposed for verifying the mathematical model of a contactless DC motor using the Simulink program. The use of dynamic (current transient characteristics) and static characteristics (adjustment characteristics) obtained by mathematical modeling are considered. According to the model transient processes, it is proposed to determine the electromechanical and electromagnetic time constants and compare them with the engine passport data. It is shown how the analysis of motor speed pulsations (calculation of the pulsation frequency value at a given speed) enables to check the correctness of the model operation.

The evaluation of the maximum possible efficiency of an idealized turbine of 1 kW with no losses in the gearbox and the inverter is made. It is shown that the turbine efficiency cannot exceed 59%. Based on the obtained mathematical model describing, the diameter of the wind turbine was calculated at the maximum efficiency value. Mathematical models describing mechanical energy conversion and electrical energy conversion are considered, which form a mathematical model of a wind turbine, presented in the form of a Simulink scheme.

Quad copter drone usually uses Brushless Direct Current (BLDC) motor as rotor due to high efficiency and small volume. The BLDC motor speed control is very important for drone position and velocity determent. The optical sensor can be used to measure the rotation speed of BLDC motor when tested in the laboratory. The calculation of rotation speed, use of Pulse Width Modulation (PWM) technique for speed control and serial interface can be implemented using a microcontroller. The purpose of this research is to control the speed of BLDC motor for ground test of drone rotor. From the measurements, the relation between speed reference signal controlled by PWM and actual speed are not linear due to time constant and fan load. The increase of PWM duty cycle produces the increase of motor speed. The regulating characteristics of motor can be used for speed control correction.

The article considers actual problems of the Internet environment development for master’s degree students. Results of the analysis of university portals and social networks regarding their relevance for organization of research and innovative activity of master’s degree students are cited. The authors conclude that it is necessary to create a special Internet environment for this category of trainees. The structure and implementation of the environment are justified.

This paper describes approaches to the calculation of back-emf coefficient, torque constant and flux linkage. These parameters are necessary for the mathematical simulation of a brushless DC (BLDC) motor and are used as input parameters. The article gives an example of calculations for a 5 kW brushless DC motor HPM5000B. In addition, a verification method is proposed to check these parameters' validity through a library module Permanent Magnet Synchronous Machine.

The amount of energy consumed by a heating system is significantly influenced by the number of radiator sections and the temperature at the forward feeder. Changing the number of radiator sections affects the amount of emitted heat energy and, consequently, the temperature of the heat conductor on the return-line. This article describes the prototype of an expert system providing an optimal design of the heating circuit. This system is designed to perform an automatic search of optimal energy consumption based in its turn on two parameters: the number of radiator sections and the temperature at the forward feeder.

This paper reviews permanent magnet synchronous motor vector control techniques and existing classifications of such techniques. This paper offers a generalized classification of vector control techniques that combines various principles of vector control and speed control approaches. Methods listed in the classification are characterized by their basic qualitative characteristics. On the basis of comparative analysis of techniques recommendations are given on their practical application.

This article considers the results of a survey of the Internet space in order to identify interest and ideas about innovative activities and readiness for it. Understanding of the essence of innovation activity by respondents, its effectiveness, participation in innovation competitions, awareness of leading innovative programs, participation in the registration of intellectual property and other aspects are considered in the article. The results of the survey reveal the preservation of diversity of points of view with the prevalence of a significant change in interest and innovation activity.

This paper presents the mathematical description of cascade control servo system of the feed drive. A neural network controller is developed in MATLAB/Simulink environment. The comparison between neural network controller and the traditional P-controller is discussed.

This article discusses the method of indirect measurement of speed based on the information received from the rotor position sensor. The method is to implement numerical differentiation using polynomial interpolation. The paper evaluated the accuracy and speed of the method of polynomial interpolation. Speed is defined for modern 32-bit microcontrollers Microchip dsPIC33F and Atmel AVR32UC.

The method of field weakening, which provides constant power at a constant current, is examined. This method is based on maintaining constant steady-state values for projections of stator current on the longitudinal and transverse axes of a synchronous motor. The projection of stator voltage on the longitudinal axis remains unchanged, but the projection of stator voltage on the transverse axis depends on speed. To assess the effectiveness of this method, a mathematical model of the electric drive was developed with vector control and a field-weakening module. From this model of the working of the electric drive, the mechanical characteristics and dependence of efficiency on the speed of the motor were established using the program Simulink.

The St. Petersburg State Electrotechnical University «LETI» is one of the leading technical higher education institutions in Russia. The present article takes it as an example of a technical school to review problems faced by technical higher education institutions which train personnel and carry out researches in the fields of Electric Power and Electric Engineering, Control in Engineering Systems, Mechatronics and Robotics. The article presents a classification of enterprises which are potential partners of the higher education institution. It also presents suggestions how to overcome the situation.

Modeling of numerical differentiation of position sensor signals is carried out. Formulas with variable number of terms of series are compared. Accuracy ranking for each equation is done.

Currently in use numerical differentiation of position sensor signals method consisting in derivative calculations by logarithmic differentiation is considered. The new speeded up derivative calculation method compared with the previous one is brought forward. Generalized mathematical operations quantity-counting formulas for either method with variable number of series terms are obtained. The numerical differentiation calculation time estimation for a microcontroller is given.

The article is devoted to creation of clarified mathematical model of stepper motor in Simulink. The main advantage of this model is opportunity for further development to taking into account the steps missing and torque drops which could not be accounted for the hybrid stepper motor library block.