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This article shows the possibility of more effective control of an asynchronous motor with a squirrel- cage rotor than in the formation of an electromagnetic torque under flux linkage stabilization. A comparative analysis of energy properties of asynchronous machine operation under different kinds of control in similar conditions was performed. One means of control provides the premagnetization of the motor and creates electromagnetic torque upon stabilization of the rotor flux linkage in the first control zone, ensuring a transition into the second zone. In another means of control, in accordance with the developed method of sequential synthesis, premagnetization of the motor is not carried out, and at a low rotor rotational speed creates the electromagnetic torque with a minimum of total loss. When the speed increases, the electromagnetic torque is created under the stabilization of efficiency owing to reducing the reactive power in the function of the rotor-rotation speed. With a further increase in speed, the control is fulfilled with a minimum of reactive power, regardless of the motor load. The energy properties of the motor operation were compared depending on the load and rotation speed under the different means of control. The change in the energy properties of electric-drive operation when generating a motor angular velocity up to double the rate under conditions of limitation of voltage of the power-supply source was considered.

The present work is devoted to the investigation of two-channel control algorithm of electromechanical vibration exciter that provides a free rotational motion of the unbalanced masses. A squirrel-cage induction motor was considered as a drive motor for the unbalance vibration exciter. Proposed control algorithm allows to start an induction motor without its premagnetization, as well as to provide a free rotational motion of the unbalanced masses in a quasi-steady state using vector control principles. Synthesis of the controllers for the control system was performed. Simulation modeling of the developed system was carried out in the MATLAB/Simulink software package, as a result of which system’s dynamic characteristics were calculated. The simulation results shows that proposed control structure allows to significantly reduce the copper losses for magnetization of the unbalance vibration exciter induction motor drive in comparison with the classical systems.

The present work is devoted to the design of the energy-efficient control algorithm for an induction motor drive of an electromechanical unbalance vibration exciter. The control law under consideration consists in maintaining the direct and quadrature components of the stator current at the same level. Such an algorithm allows to minimize the effective values of the stator phase currents. A synthesis of the control system using this algorithm was carried out on the example of the selected induction motor drive. For the comparative analysis of the results, the control system for the electromechanical unbalance vibration exciter with the similar power unit and the constant reference of the rotor flux linkage was also synthesized. The dynamic characteristics of the developed systems were calculated in the MATLAB/Simulink software package. The simulation results showed the efficiency of the developed control algorithm for the induction motor drives of the unbalance vibration exciters.

The possibility of movements' separation in the unbalance vibration exciter induction motor drive is shown in the paper. The unbalance vibration exciter induction motor drive control system has been synthesized on the base of the movements' separation principle. The digital simulation of the synthesized system has been conducted and its dynamic characteristics are presented. The advantages of the movements' separation principle as applied to the system under study are shown.