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DETERMINATION OF STEADY TEMPERATURE AND THE TIME CONSTANT OF HEATING COILS IN ROTARY ELEC-TRICAL MECHINES USING THE NUMERICAL EXTRAPOLATION
Dragan T. Stanković
In order to determine a steady value of heating temperature increase θu as well as time constants of heating coils in T rotary electrical machines, the paper presents the application of numerical extrapolation of rotary electrical machines cooling curve instead of graphical extrapolation recommended by the standards. The error of change of coil electric resistance in determining θu and T values is analysed, the factors influencing the size of errors in percents are given and optimal conditions for the method application are presented as well.
Ključne reči: Rotary electrical machines, coils, heating temperature, time constant, numerical extrapolation, error in percents. |