Mechanical vibration suppression on multi-sector PMSM with optimal active vibration control

The proposed paper presents an active vibration suppression technique for a multi three-phase permanent magnet synchronous machine equipped with mechanical bearings. The mathematical model of the radial force and torque generation of the considered machine is introduced at first. In this work the radial force is exploited to damp mechanical vibrations detected on the machine housing. The state space representation of the mechanical plant is provided and employed to design the active vibration control. The latter consists of multiple resonant controllers each of them tuned to suppress one specific harmonic of vibration. In this study two different vibration harmonics are considered, hence the active vibration control consists of two resonant controllers placed in parallel. The linear quadratic regulator technique has been employed to select the optimal controller gains in the whole speed range. The technique is then validated in the Matlab-Simulink environment showing that the active vibration control can effectively suppress the detected vibrations.