Fault Diagnostics for Electrically Operated Pitch Systems in Offshore Wind Turbines

Surya Teja Kandukuri,Van Khang Huynh,Kjell Gunnar Robbersmyr,Hamid Reza Karimi

doi:10.1088/1742-6596/753/5/052005

Surya Teja Kandukuri, Van Khang Huynh + Show 2 more

Open Access

https://doi.org/10.1088/1742-6596/753/5/052005

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Abstract

This paper investigates the electrically operated pitch systems of offshore wind turbines for online condition monitoring and health assessment. The current signature based fault diagnostics is developed for electrically operated pitch systems using model-based approach. The electrical motor faults are firstly modelled based on modified winding function theory and then, current signature analysis is performed to detect the faults. Further, in order to verify the fault diagnostics capabilities in realistic conditions, the operating profiles are obtained from FAST simulation of offshore wind turbines in various wind conditions. In this way, the applicability of current signature analysis for fault diagnostics in offshore wind turbine pitch systems is demonstrated.

Highlights

Offshore wind is among promising renewable energy industries growing at a rapid pace
This paper investigates the electrically operated pitch systems of offshore wind turbines for online condition monitoring and health assessment
The motor current signature analysis based on Fast Fourier transform (FFT) is tested in wind turbine pitch system scenario for detecting pitch motor faults

Summary

Introduction

Offshore wind is among promising renewable energy industries growing at a rapid pace. In order to gain insight into the pitch system operation, the specifications of the pitch motor, gearbox and blade bearing are required for simulation study This information is not generic and vary with turbine model. It is to be noted that the ratio of number of poles to the rotor bars plays a significant role in the detectability of AGE fault in an induction motor [27]. Only outer race fault is simulated and it can be seen that the bearing fault frequencies are detected in the single phase current spectrum as described by: fBRG = |fs ± kfc|, k = 1, 2, 3. All the described faults of induction motor are physically simulated at supply frequency and the effect of fault severity and variation of load are studied. The closed loop behaviour of the induction motor shall be evaluated

Faulty machine behaviour in closed loop

Findings

Conclusion