Finite Element based Vibration Signature analysis of electrical Propeller Drive System for condition monitoring

Any defect in the form of an axial crack or a circular defect in the propeller induces additional component in the centrifugal force and thereby producing an additional vibration characteristic in the propeller. The objective of this paper is to determine the translation of vibration to the permanent magnet synchronous machine (PMSM) which drives the propeller and in turn a triaxial accelerometer is used to detect the faults. A finite element based model is created consisting of the propeller, shaft, bearings and PMSM. The FEA modal analysis is performed to determine the natural frequency of the system and a harmonic response analysis is performed to determine the vibration harmonics at the natural frequency of the system. A comparison of the natural frequencies of the healthy system and the defective systems are obtained along with vibration characteristics for the different profiles and the load dependency of the vibration characteristics. It is observed that the x-axis and z-axis vibrations increase significantly for the defective propeller and it increases with load.