Electromechanical transducer for drying and processing of coal concentrates and sludges

Purpose. Determination of the effect of perforations in the hollow ferromagnetic rotor on dynamic characteristics of the electro-mechanical transducer. Methods. Calculation of the dynamic characteristics of the electromechanical transducer with a hollow smooth and perforated rotor was performed using the theory of the general electrical machine, as well as the numerical solutions of differential equations by finite elements' method in three-dimensional statement. Findings. The paper presents the research into the impact of rotor holes on the form of dynamic characteristics, which was carried out on the basis of comparing characteristics of the electromechanical transducer with those of smooth and perforated rotor. Introduction of rotor perforations brings about downward transposition of the mechanical dynamic characteristic parallel to itself. Starting the transducer with hollow ferromagnetic rotor, compared to starting the basic asynchronous motor, has a lower amplitude and smaller number of pulsations of electro-magnetic shock torque. We suggest calculating the dynamic characteristics of the electromechanical transducer with a hollow ferromagnetic rotor by way of combining the generalized theory of electrical machines with numerical solution of finite elements' method in three-dimensional statement. This approach was tested by juxtaposing the calculated and experimental data obtained for the physical model of the transducer with a hollow ferromagnetic rotor. Originality. Dynamic characteristics of the electromechanical transducer with a hollow smooth and perforated rotor were obtained for starting with ventilation load. Practical implications. The study results allow to expand the scientific theoretical basis of asynchronous machines with a ferromagnetic rotor and can be used to optimize the design and improve the efficiency of implementing electromechanical transducers with a hollow perforated rotor.