An investigation of the dynamic electromechanical coupling effects in machine drive systems driven by asynchronous motors

• Analytical model of the driven machine–asynchronous motor system.
• Attenuation of vibration resonances caused by the electromagnetic damping.
• Increase of the mechanical natural frequencies due to electromagnetic stiffening.
• Induction of severe low-frequency torsional vibrations by the asynchronous motor.
• Estimation of electromechanical coupling severity using dynamic characteristics.

In the paper dynamic electromechanical interaction between the rotating machine drive system and the electric driving motor is considered. The investigations are performed by means of the circuit model of the asynchronous motor as well as using an advanced structural hybrid model of the drive system. Using the analytical solutions applied for the electrical and the mechanical systems the electromagnetic stiffness and coefficient of damping, both generated by the electric motor rotationally interacting with the mechanical system of the given dynamic properties, were determined. By means of experimentally validated computational responses obtained for torsional harmonic excitation induced by the driven machine working tool, a modification of dynamic properties of the mechanical system by the electromagnetic flux between the stator and the rotor has been studied.