On the Issue of Assessing the Thermal Stability of the Electric Machine Rotor Based on Experimental Research of Its Heating

The results of the research of the thermal state of the active zone of the smooth rotor of a powerful full-scale electric machine in asynchronous modes are given. A comparison with the results of experimental research of temperatures is made based on the developed complex methodological and software support for numerical mathematical modeling and calculation of physical fields by the finite element method and data from full-scale tests of the machine. The discrepancies between the obtained theoretical values of heating on the surface are analyzed in comparison with the experimental values for the depth of the rotor array. Differences in the maximum calculated and actually measured temperatures are established. Their values may exceed 50°/0, and in the initial sections of the short-term process - more than 100%, which thus negatively affects the assessment of the “true” thermal stability of the structure only on the basis of experimental data. It is shown that thermal processes in the rotor are also a factor limiting the load of the electric machine when operating in long-term slip modes.