Designing of alternating-current drive with reduced noise level

Abstract

The reduction of the noise level and vibrations of a modern electrical drive are very significant problems during its development. The methods for solving this problem in the context of traditional threephase electromechanical systems are rather well studied but, however, have exhausted themselves in many respects. One promising variant for designing alternating-current asynchronous and synchronous motor drives with enhanced vibronoise characteristics is constructing it based on an actuating motor with an increased number of phases. On the one hand, the reduction of the noise and vibrations via application of multiphase machines (m > 3) is conditioned by a decrease in tangential forces caused by pulsations of the electromagnetic torque of the motor. This is connected with the fact that an increase in the number of phases of the stator winding causes the sparseness of the harmonic composition of the field in the air gap and the elimination of asynchronous harmonics from it with a relative increase in synchronous ones. On the other hand, an increase in the number of phases substantially expands the possibilities for noise level reduction because of a decrease in radial magnetic forces acting between the stator and the rotor and causing dynamic deformations of the stator ring. Techniques for optimization of vibronoise characteristics of the asynchronous and synchronous motor drives and realization of their control system structure are proposed. Results of investigations of multiphase electromechanical systems that show the efficiency of the proposed solutions are given.