Planetary gearbox effects on induction machine in wind turbine: Modeling and analysis

Wind energy´s contribution to electricity supply is significantly increasing. As a result, reliability of the wind turbine becomes crucial. Gearbox is known as one of the most critical subassemblies of the wind turbine in which failures could lead to a long-term and high cost downtime. Recently, electrical signature analysis has been considered as an alternative for vibration monitoring in order to detect both electrical and mechanical faults in a cheap, easy to install and accessible way. This paper aims to monitor the planetary gearbox effect of a wind turbine on the wound rotor induction generator using electrical signature. For that, dynamic model of a single stage planetary gearbox have been implemented. The proposed model includes essential non-linearities such as time varying mesh stiffness, transmission error and damping force. Simulation results clearly show that electromagnetic torque and stator current of generator contain mesh and rotating related frequencies of the gears in its spectra.