Fracture Analysis of a Cycloidal Gearbox as a Yaw Drive on a Wind Turbine


  • Jairo Aparecido Martins DESCH North America, Cambridge, Ontario, Canada
  • Estaner Claro Romao University of Sao Paulo, Brazil
Volume: 14 | Issue: 1 | Pages: 12640-12645 | February 2024 |


Fast growth of renewable energies has required addressing challenges such as generating the largest energy production possible throughout the equipment's lifespan and between its preventive and corrective maintenance intervals. Actions such as preventive maintenance, and improvement of the main components, mainly when it comes to reliability and predictability are of extreme importance to reach maximum generation. Due to the importance of the yaw drives for wind turbines, this paper aims to evaluate a failure that occurred on a cycloidal gearbox used in a drive of this kind. For the evaluation of the yaw drive, all the components were analyzed to determine the incurred fracture mechanism. Such analysis was performed by mapping all components, conducting a hardness test to check the components' mechanical properties, analysis of the fractured surfaces of the cycloidal disc, and numerical simulation (linear elastic) via the Finite Element Method (FEM) to check the stress distribution on the fractured part (cycloidal disc) under load, and theoretical calculation of the cycloidal disc lifespan. In addition, the stress distribution by FEM was compared with the broken regions of the physical part. To sum up, after all the evaluations, it is possible to claim the results demonstrate there was a premature fracture of the cycloidal disc that occurred due to the phenomenon of high cycle fatigue.


Finite Element Method (FEM), fracture analysis, yaw drive, numerical simulation


Download data is not yet available.


IEA, Renewables 2021 - Analysis and forecast to 2026. Paris, France: International Energy Agency, 2021.

M. Mahmoud, M. Ramadan, A.-G. Olabi, K. Pullen, and S. Naher, "A review of mechanical energy storage systems combined with wind and solar applications," Energy Conversion and Management, vol. 210, Apr. 2020, Art. no. 112670.

J. A. Ferraz de Andrade Santos, P. de Jong, C. Alves da Costa, and E. A. Torres, "Combining wind and solar energy sources: Potential for hybrid power generation in Brazil," Utilities Policy, vol. 67, Dec. 2020, Art. no. 101084.

S. Usha, M. S. Abishake, G. Anbezhil, and S. Dhanasekar, "Increasing the wind power generation by modifying the windmill mechanism," Materials Today: Proceedings, vol. 72, pp. 3075–3080, Jan. 2023.

W. J. Florkowski and J. Rakowska, "Review of Regional Renewable Energy Investment Projects: The Example of EU Cohesion Funds Dispersal," Sustainability, vol. 14, no. 24, Jan. 2022, Art. no. 17007.

M. F. Hairani and S. A. Jumaat, "Development of Double Mini Windmill with Smart Monitoring System," Journal of Electronic Voltage and Application, vol. 3, no. 2, pp. 59–66, Dec. 2022.

R. Zheng, Y. Zhou, and Y. Zhang, "Optimal preventive maintenance for wind turbines considering the effects of wind speed," Wind Energy, vol. 23, no. 11, pp. 1987–2003, 2020.

Y. Aafif, A. Chelbi, L. Mifdal, S. Dellagi, and I. Majdouline, "Optimal preventive maintenance strategies for a wind turbine gearbox," Energy Reports, vol. 8, pp. 803–814, Nov. 2022.

T. L. Baun, "Wind Turbine Generator with Service Platform and Associated Method," US20230059355A1.

Guidelines for Design of Wind Turbines, 2nd ed. Copenhagen, Denmark: DNV/Risø, 2002.

M.-G. Kim and P. H. Dalhoff, "Yaw Systems for wind turbines – Overview of concepts, current challenges and design methods," Journal of Physics: Conference Series, vol. 524, no. 1, Mar. 2014, Art. no. 012086.

"Wind Turbine Yaw System: Introduction," Windmills Tech, Nov. 17, 2022.

S. Bednarczyk, "Cycloidal Planetary Transmission," Ph.D. dissertation, Wroclaw University of Technology, Wroclaw, Poland, 2014.

M. Wiklo, R. Krol, K. Olejarczyk, and K. Kolodziejczyk, "Output torque ripple for a cycloidal gear train," Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, vol. 233, no. 21–22, pp. 7270–7281, Nov. 2019.

K. Olejarczyk, M. Wiklo, and K. Kolodziejczyk, "The cycloidal gearbox efficiency for different types of bearings—Sleeves vs. needle bearings," Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, vol. 233, no. 21–22, pp. 7401–7411, Nov. 2019.

"Design and Engineering," Innovative Automation, Aug. 31, 2022.


"Fusion 360 Help ," Autodesk,

J. A. Martins and E. C. Romao, "The Importance of Accurate Boundary Condition in Obtaining Reliable Shearing Stresses on a Torsional Finite Element Simulation," Engineering, Technology & Applied Science Research, vol. 12, no. 3, pp. 8482–8487, Jun. 2022.

E. C. Romao and L. F. M. de Moura, "3D contaminant transport by GFEM with hexahedral elements," International Communications in Heat and Mass Transfer, vol. 42, pp. 43–50, Mar. 2013.

J. A. Martins and E. C. Romao, "Analyzing 2D segment by Multiphysics in heat transfer and solid mechanics, pondering variables by Design of Experiment (DOE)," Engineering Science and Technology, an International Journal, vol. 19, no. 4, pp. 1929–1935, Dec. 2016.

E. C. Romao and L. H. P. de Assis, "Numerical Simulation of 1D Unsteady Heat Conduction-Convection in Spherical and Cylindrical Coordinates by Fourth-Order FDM," Engineering, Technology & Applied Science Research, vol. 8, no. 1, pp. 2389–2392, Feb. 2018.

W. R. do P. Junior, J. A. Martins, and E. C. Romao, "Utilizing Numerical Simulations to Analyze the Efficiency of a Porous Reactor," Engineering, Technology & Applied Science Research, vol. 12, no. 3, pp. 8755–8759, Jun. 2022.

G. E. Dieter, Mechanical Metallurgy. New York, NY, USA: Mc Graw-Hill, 1986.

R. W. Hertzberg, R. P. Vinci, and J. L. Hertzberg, Deformation and Fracture Mechanics of Engineering Materials, 5th edition. Hoboken, NJ, USA: Wiley, 2012.

F. Kun, H. A. Carmona, J. S. Andrade, and H. J. Herrmann, "Universality behind Basquin’s Law of Fatigue," Physical Review Letters, vol. 100, no. 9, Mar. 2008, Art. no. 094301.

H. Mughrabi and H. W. Hoppel, "Cyclic deformation and fatigue properties of very fine-grained metals and alloys," International Journal of Fatigue, vol. 32, no. 9, pp. 1413–1427, Sep. 2010.

S. Kwofie, "An exponential stress function for predicting fatigue strength and life due to mean stresses," International Journal of Fatigue, vol. 23, no. 9, pp. 829–836, Oct. 2001.

M. Yang et al., "High-Cycle Fatigue Behavior and Fatigue Strength Prediction of Differently Heat-Treated 35CrMo Steels," Metals, vol. 12, no. 4, Apr. 2022, Art. no. 688.

D. G. Zisopol, D. V. Iacob, and A. I. Portoaca, "A Theoretical-Experimental Study of the Influence of FDM Parameters on PLA Spur Gear Stiffness," Engineering, Technology & Applied Science Research, vol. 12, no. 5, pp. 9329–9335, Oct. 2022.


How to Cite

J. A. Martins and E. C. Romao, “Fracture Analysis of a Cycloidal Gearbox as a Yaw Drive on a Wind Turbine”, Eng. Technol. Appl. Sci. Res., vol. 14, no. 1, pp. 12640–12645, Feb. 2024.


Abstract Views: 90
PDF Downloads: 85

Metrics Information

Most read articles by the same author(s)