Review of Fault Detection and Diagnosis Methods including Failure Root Causes of Major Components of Hydraulic Pitch System for Wind Turbines Part-II

Authors

  • Mohit Bhola AAU Energy, Mechatronics Section, Aalborg University, Aalborg, Denmark
  • Gyan Wrat AAU Energy, Mechatronics Section, Aalborg University, Aalborg, Denmark
  • Henrik C. Pedersen AAU Energy, Mechatronics Section, Aalborg University, Aalborg, Denmark https://orcid.org/0000-0002-1034-3280
  • Jesper Liniger AAU Energy, Esbjerg Energy Section, Aalborg University, Esbjerg, Denmark https://orcid.org/0000-0001-8775-3918
  • Diego M. Chamorro AAU Energy, Mechatronics Section, Aalborg University, Aalborg, Denmark

DOI:

https://doi.org/10.13052/ijfp1439-9776.2644

Keywords:

Hydraulic Pitch System, Wind Turbine, Fault Tree Analysis, Failure Root Causes

Abstract

The hydraulic pitch system is a critical component of modern wind turbines, responsible for both power regulation and safety mechanisms. Ensuring the reliability and availability of this system is essential for optimal turbine performance. This study focuses on the reliability of less active yet essential components within the hydraulic pitch system, including the pump, accumulator, relief valve, hose, and hydraulic oil. The hydraulic oil in the analysis has been treated as a component also. Employing a comprehensive Fault Tree Analysis (FTA), this study identifies the failure modes, effects, and root causes of these components. Key findings indicate that contamination and inadequate maintenance are primary contributors to failures. The study discusses various fault identification and condition monitoring algorithms, including those based on artificial intelligence and machine learning, which are effective in post-processing data for fault detection. Physics-based models, such as observer methods like the Kalman Filter, show potential for real-time implementation. The findings underscore the importance of stringent filtration, regular inspections, and proactive maintenance strategies, including monitoring accumulator pre-charge pressure and using appropriate hydraulic oil. Addressing these root causes can significantly enhance the reliability and longevity of hydraulic pitch systems, thereby improving the overall performance and safety of wind turbines.

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Author Biographies

Mohit Bhola, AAU Energy, Mechatronics Section, Aalborg University, Aalborg, Denmark

Mohit Bhola is currently working as a Post Doctoral Researcher at the Mechatronics Section, Energy Department at Aalborg University located in Aalborg, Denmark. He holds a PhD degree in Mechatronics from the Indian Institute of Technology (Indian School of Mines), Dhanbad, India. His current research interests are Fault Tolerant Control of Hydraulic Pitch Systems for Wind Turbines, Digital Hydraulics, Hybrid Hydrostatic Transmission Systems, System Modeling, Control, Hardware in Loop (HIL) Simulations, and Automation.

Gyan Wrat, AAU Energy, Mechatronics Section, Aalborg University, Aalborg, Denmark

Gyan Wrat is a Post Doctoral Researcher at Aalborg University in the Energy Department, currently researching wind turbine technology. He holds a PhD and a Master’s degree in Mechatronics from the Indian Institute of Technology, India. His research interests lie in the field of Fluid Power Fault and Control.

Henrik C. Pedersen, AAU Energy, Mechatronics Section, Aalborg University, Aalborg, Denmark

Henrik C. Pedersen is an Associate Professor and Head of Section for Mechatronic Systems at the Department of Energy at Aalborg University, Denmark. His field of work is in the analysis, design, optimization, and control of mechatronic systems in general and fluid power systems and components in particular. Special focus is on efficiency, reliability, condition monitoring, fault detection and diagnostics, and control of fluid power systems and components. Author of >170 publications within these areas and project leader (P.I.) for several research projects within this and related areas.

Jesper Liniger, AAU Energy, Esbjerg Energy Section, Aalborg University, Esbjerg, Denmark

Jesper Liniger is an Associate Professor at Department of Energy, Aalborg University, Denmark. His research interest includes fault analysis and fault detection in fluid power and perception and navigation in subsea robotics.

Diego M. Chamorro, AAU Energy, Mechatronics Section, Aalborg University, Aalborg, Denmark

Diego M. Chamorro is working as a Research Assistant at the Mechatronics Systems section at AAU Energy, investigating accelerated testing methodologies in fluid power systems. He holds a Master’s degree in Mechanical Engineering focusing on tribology from the TRIBOS Consortium. His research interests are Mechatronics systems, Tribology, and Fluid power systems.

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Published

2025-12-28

How to Cite

Bhola, M. ., Wrat, G. ., Pedersen, H. C. ., Liniger, J. ., & Chamorro, D. M. . (2025). Review of Fault Detection and Diagnosis Methods including Failure Root Causes of Major Components of Hydraulic Pitch System for Wind Turbines Part-II. International Journal of Fluid Power, 26(04), 625–672. https://doi.org/10.13052/ijfp1439-9776.2644

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