Vol 90, No 5 (2019)

Synchronous reluctance electric drives are being developed due to their advantages of contactlessness, high overload and specific torques, absence of loss in the rotor, and large control range, as well as progress that is being made in the fields of information and power electronics. It is shown that iron loss significantly affects the control algorithms for synchronous reluctance machines. A four-loop vector control system of a synchronous reluctance machine is considered. The main ducts are the current and electromagnetic torque control circuits of the electric machine and the secondary ducts are the stator flux linkage and angular velocity contours. The features of observer synthesis for vector control system taking into account iron losses and magnetic saturation of the system are given. By means of experimental studies, the adequacy of the received observer was shown. The synthesis of algorithms for optimal control of the synchronous reluctance machine, taking into account iron loss, is given. The first algorithm assumes the existence of a table with optimal values of control actions. The second provides for the synthesis of an adaptive torque controller, which will be automatically tuned to the optimal control action. The obtained control algorithms are universal and can be applied in other control systems of synchronous reluctance machines, for example, in direct torque control systems.

This article proposes a technique for selecting power electric equipment and an algorithm for synthesizing the control system of critical works of metallurgical production by the example of the pipe rotation electric drive of the cold rolling mill at JSC Chelyabinsk Pipe Plant. The optimal parameters of the power parts of the electric drive were chosen against the maximum response speed criterion, which allowed improving the overall output of ultrafine-wall pipe production. It is shown that the amplitude of self-oscillations conditioned by the finite stiffness of the transmission between the engine and the actuating device can be restricted by selecting an appropriate gear ratio for the reducer. Simplification of the system’s mechanical transmission made it possible to reduce mechanical losses and more easily to adjust the electric drive with a load described in the two-mass system, but required uprating the installed capacity by around 100%. The parameters of corrective devices of electromagnetic torque, speed, and position adjustment loops were determined by the classical techniques of frequency analysis and synthesis. As shown by analyzing transient process curves, the response speed of the rotation electric drive was increased by around 80% and the overall output rate of the mill by 15 to 20%. The expected annual economic effect of the adopted engineering solutions amounts to around 250 million rubles.

The rated engine speed and torque of an engine are calculated against the criterion of minimum losses and on the basis of the load graph of the traction electric drive of the Gazelle-Next electric vehicle (EV). It is shown that this approach allows making the system more efficient by around 10%. A mathematical model of the system is developed, where the traction torque indirect adjustment loop is approximated by aperiodic first-order links one of which takes into account uncompensated electromagnetic response delays of phase circuits, whereas the other approximately takes into account the restricted response time of the microprocessor control system. The suggested procedure of synthesizing the traction electric drive control system allows reducing the self-oscillations of the object operated in the zone of torque and speed overloads. It is found that the best adjustment figures for traction mechanisms used in complex operating conditions are reached in the structure with an internal corrective loop against the active capacity coordinate. This is due to the possibility of directly measuring the coordinates of phase current and voltage, which ensures the zero lag of the feedback line. The system adjustment quality was evaluated for the “Traction effort-output speed” line, which involved modeling glare ice as the most complicated running mode for the electric drive, when the traction drive changes from peak to zero almost according to the step law. In this case, the speed coordinate was readjusted by no more than 8%.

A high-temperature starter-generator with an outer rotor and the possibility of arranging it on the high-pressure shaft of ab aircraft engine are considered. The materials to manufacture this starter-generator were selected, numerical calculations of it were performed, and various world analogs were considered. Based on the obtained data, a multicriterion optimization of the design scheme was performed by means of a genetic algorithm and the Pareto method. As a result of optimization, a Pareto optimal active length and thickness of permanent magnets of the starter-generator were chosen. Using the obtained sizes made it possible to reduce the weight of the designed starter-generator by 10 kg relative to the basic variant (of the foreign high-temperature starter-generator produced by Thales) with invariable thermal loads. On the basis of the optimal geometrical dimensions, a multidisciplinary computer simulation (interdependent thermal, electromagnetic, and mechanical calculations) was performed, as a result of which the viability of the designed structure was demonstrated.

The electromechanical converters with levitation elements of different purposes are considered. The magnetic, electric, thermal, and mechanical parameters of converters are subdivided into fixed and variable parameters. The relative transformation of parameters is presented in general terms. In the process of developing the design procedure of converters, the principle of proportionality of overall dimensions, the displacement of the magnetic field between the exciting winding and levitation element, and the procedure of calculating the effect of impulsive forces are defined. To choose a material for the levitation element, Fourier and Wiedemann-Franz laws are used.

The benefits of the Advanced Surface Movement Guidance and control system (ASMGCS) are considered. The need for ASMGS-based renovation of existing airfield lighting systems through associated data and power channels is shown. The structure of the upgraded solution is proposed, and the unit functions added to the structure are described. A number of key tasks is determined. It is shown that the frequency properties of the combined power and data channel is need to be studied. Conclusions and recommendations are made for the further development of such a system.