“Online Load and Leakage Estimation in Hydraulic Pitch System for Wind Turbines”
Authors: Casper S. Pedersen, Magnus Fink, Mohit Bhola and Henrik C. Pedersen,Affiliation: Aalborg University
Reference: 2025, Vol 46, No 3, pp. 111-122.
Keywords: Unscented Kalman Filter, Load Estimation, Leakage Estimation, Wind Turbine Pitch System
Abstract: In wind turbines, the pitch system is a critical subsystem for both regulating the power output and for the safety of the turbine. However, it is also one of the leading contributors to downtime in turbines, as it is prone to faults like internal and external leakage. In this article, a novel method for estimating load and leakage in hydraulic pitch systems is presented. The proposed method is based on Unscented Kalman Filters, where the method integrates load estimation to handle the stochastic nature of wind loads, enhancing the accuracy of leakage detection. Based on the developed method, simulation and experimental results are presented that demonstrate the feasibility and robustness of the method under varying operating conditions and for different parameter variations. From the results, it is therefore found that the method shows good promise for being applied in condition monitoring and fault detection in pitch systems and may therefore be used to reduce downtime and maintenance costs in wind turbine operations.
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BibTeX:
@article{MIC-2025-3-2,
title={{Online Load and Leakage Estimation in Hydraulic Pitch System for Wind Turbines}},
author={Pedersen, Casper S. and Fink, Magnus and Bhola, Mohit and Pedersen, Henrik C.},
journal={Modeling, Identification and Control},
volume={46},
number={3},
pages={111--122},
year={2025},
doi={10.4173/mic.2025.3.2},
publisher={Norwegian Society of Automatic Control}
};