Investigation of the Temperature Condition of Electric Motors Using the Comsol Package

Abstract

Operation of electric drives in agroindustrial complex has confirmed the necessity of controlling the temperature condition of electric machines. Overheating of electric motor can occur due to its operation in a non-nominal mode, including the change of rotor speed. For adequate adjustment of electric motors temperature protection systems and maximum use of their overload capacity it is necessary to have mathematical models of states, taking into account real operating conditions and changes of operating mode. It is proposed to carry out such modeling in the Comsol software. Taking into account the previously obtained aerodynamic models, the model of thermal state of electric motor is implemented in this software. Patterns of thermal fields both outside the electric machine and inside were obtained. The simulation was carried out at different rotor speeds and taking into account the cooling air temperature. It was confirmed that the most heated part is the frontal part of stator windings. Results of simulation showed that the temperature of the most heated parts of the electric motor corresponded to the maximum permissible value for the given class of insulation. Thermal imaging of the electric motor has proved the adequacy of the simulation to the real values of the temperature of the outer shell of the electric machine. The experiment with built-in thermocouples in the most critical places of the electric motor has also proved the correspondence of temperature data to the data obtained during modeling.