Application of hybrid excitation in a DC motor for drive of transport rolls in metallurgical industry

Abstract

Purpose. To determine the effectiveness of the application of hybrid excitation for DC motors of medium power. Estimate the influence of the location of the permanent magnet of the main pole core on the magnitude of the magnetic flux created by it. Methodology. The classical theory of electric machines, the calculation of the magnetic field by the finite element method and analytical comparison were used to conduct the research. Results. The feasibility of using hybrid excitation for DC motors of medium power has been confirmed. The use of hybrid excitation in an experimental direct current motor made it possible to increase the excitation magnetic flux by 11%. This will make it possible to reduce the current load of the excitation winding, increase the reliability of the motor and reduce electrical losses on the excitation. The optimal location of the permanent magnet, according to the criterion of the maximum magnetic excitation flux, is its location at the main pole shoe along the air gap. Originality. The difference between the conducted research and others is that the condition of the research was to keep the dimensions of its motor, the excitation winding and the interpoles winding unchanged. Practical value. The obtained results will allow the designers of dc motors with hybrid excitation to avoid wrong decisions during further research and development of these motors.