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This paper deals with the operating modes of a 3-degree-of-freedom (3-DOF) electric machine. The design of such a machine allows the rotor axis to rotate along two angular coordinates in a limited range of angles. This is necessary for the machine to operate as part of a small-sized, high-speed precision target detection and tracking system. Based on the 3-DOF machine dynamics model, a block diagram of a servo system has been developed for controlling the rotor motion trajectory at two coordinates. Examples are given of the implementation of rotor motion trajectories with linearly increasing Examples are given of the implementation of rotor motion trajectories with linearly increasing, as well as described by an Archimedes spiral reference signals described by an Archimedes spiral reference signals. Dependencies of the modules of the relative accuracy of rotor movement along given trajectories on the system tunings were obtained. Ref. 12, fig. 9, table.

This paper is devoted to the problems of developing an electric machine with two-degrees-of-freedom (2-DOF) of rotor movement and its control system. The structure of the machine with the possibility of rotation of the rotor along two angular coordinates in a limited range of rotation angles is considered. The machine is designed to control the position of the axis of the optical beam along the line and frame trajectories. Based on the electrodynamic state model of the 2-DOF electric machine, a block diagram of the servo system was developed to control the trajectory of the rotor in two coordinates. Relationships between the time constant of the angle controller and the time constants of the high-frequency part of the amplitude-frequency characteristic of an open-loop system are determined. The dependences of the effective values of the currents in the control windings on the frequency of the frames and the duration of the linear part of the triangular signal are obtained. The dependences of the modules of relative accuracy of the rotor movement along a given trajectories on the system tunings are obtained. Ref. 12, fig. 8.

The paper describes reactive flywheels based on brushless magnetoelectric motors for controlling the spatial orienta-tion of satellites, developed at the Institute of Electrodynamics of the National Academy of Sciences of Ukraine. The main attention is paid to the problem of implementing a rotor angular speed and position sensor, provided that it can be integrated into the motor design. The influence of the number of feedback signal pulses per one revolution of the motor shaft on the tuning of the reactive flywheel angular speed controller is studied under the condition that the ripple range at the controller output signal is limited at a given level. The dependences of the filter time constant and the con-troller gains on the value of the reactive flywheel angular speed and on the number of feedback signal pulses per revo-lution are obtained. Ref. 8, fig. 5, table.

The structure of a brushless magnetoelectric torque motor with a slotless stator with a surface installation of permanent magnets on the rotor is considered. A motor model has been developed to calculate its characteristics in the COMSOL Multiphysics 6.0 software environment. The optimization of its structure was carried out, as a result of which the opti-mal number of pole pairs and such a ratio between the dimensions of the elements of the electromagnetic core of the motor were determined, at which the maximum electromagnetic torque per unit of power consumption is achieved. The paper also touches upon the problem of achieving the minimum value of the torque ripple factor in motors of a similar design. Ways of its solution are proposed both due to constructive changes in the magnetic system, and due to the syn-thesis of reference signals for the formation of such forms of currents in the stator phases, as a result of the interaction of which with the rotating magnetic field of the rotor, the motor torque characteristic the with a minimum value of the ripple factor can be obtained. Ref. 6, fig. 11.

The paper presents the results of studies of the structure of the powers that characterize the state of a specialized brush-less magnetoelectric motor of return-rotary motion. The calculated curves of the rotor angular speed, the motor torque and the torques of mechanical resistance, and the curves of the instantaneous values of powers of consumption, useful mechanical load, and losses are given. The frequency dependences of the efficiency factor and power components are obtained based on their calculation. Ref. 7, fig. 5.

The paper describes the structure and mathematical model of a specialized brushless magnetoelectric motor of return-rotary motion. The analysis of the parameters of the mathematical model is carried out and the methods of their ex-perimental determination are described. Experimental frequency dependences of the rotor oscillations angle amplitude and the stator current effective value have been obtained. Based on the obtained parameters, the frequency characteris-tics of the motor were calculated and compared with the experimental dependences. Experimental oscillograms and calculated curves of stator voltages and currents are presented. References 7, figures 8.

In this paper, the frequency characteristics of a special brushless magnetoelectric motor of return-rotary motion with sinusoidal and rectangular forms of the carrier signal are investigated. The method of generating a feedback signal on the amplitude of the rotor shaft oscillations angle has been improved by fixing the value of the signal at the moment of reaching its amplitude. The method of calculating the control system of the oscillations angle amplitude is investigated based on the frequency characteristics of the open-loop system by setting the phase stability margin. Examples of the calculation of transient processes of regulation of the oscillations angle amplitude and the effective value of the stator current when starting the motor and changing the mechanical load are given. Ref. 9, fig. 6, tables 2.