A METHOD AND A DEVICE FOR DETERMINATION OF A TORSIONAL DEFLECTION OF A ROTATION SHAFT AND OF A DC-LINK DEGRADATION IN THE ELECTROMECHANICAL DRIVETRAIN

摘要

The subject of the invention is a method and a device for determination of a torsional deflection of a rotation shaft in the electromechanical drivetrain. The method according to the invention uses a current and voltage signals measurement of the driving electrical machine (1) and an angular speed measurement of the shaft (3) of the drivetrain and comprises the step of measuring of a voltage U_DCof the DC link unit (10) of a converter (5); the step of calculating a value of a load torque T_load of the driving electrical machine (1); the step of detecting of an oscillation O_SC(T_load) in the load torque T_load and calculation magnitudes of characteristic frequencies of Fast Fourier Transform FFT(U_DC) of the voltage U_DC of DC link unit (10); the step of determining of a timestamp indicators t_Tload for oscillations O_SC(T_load) and t_FFT of U_DC for magnitudes of characteristic frequencies of FFT(U_DC) of the voltage U_DC of DC link unit (10); the step of comparing the value of the timestamp indicators t_Tload and t_FFT and determining a torsional deflection of the rotation shaft if t_Tload t_FFT; the step of presenting the result of the comparison to the user in a diagnostic unit (6).