TY - JOUR

T1 - Reliability of electrical and hydraulic pitch systems in wind turbines based on field-data analysis

AU - Walgern, Julia

AU - Fischer, Katharina

AU - Hentschel, Paul

AU - Kolios, Athanasios

N1 - Funding Information: The present work was partly carried out within the “Fraunhofer-Innovationscluster Leistungselektronik für regenerative Energieversorgung”. The support by the Federal State of Lower Saxony with funds from “ Niedersächsisches Vorab, Germany ” (grant number VWZN2989) and by Fraunhofer-Gesellschaft, Germany as well as the provision of comprehensive field data by the project partners are gratefully acknowledged. ERA5 reanalysis data were obtained from the Copernicus Climate Change and Atmosphere Monitoring Services. Further financial support was received by EPSRC, United Kingdom through the Wind and Marine Energy Systems Centre for Doctoral Training under the grant number EP/S023801/1 .

PY - 2023/12

Y1 - 2023/12

N2 - The pitch system is notably one of the critical subsystems of a wind turbine, supporting its effective control towards maximising wind capture and at the same time protecting its integrity in cases of excessive loads. A pitching mechanism is also responsible for operational downtime, hence its reliability performance needs to be carefully evaluated so as to ensure operational availability. This study aims to derive failure rates of two configurations of pitch systems, namely the electrical and hydraulic, based on statistical analysis of a large population of onshore assets, followed by a classification of findings by turbine rating, effect of seasonality, and reliability performance of different manufacturers. The data sets underlying the present analysis are based on maintenance reports and comprise 1847 operational years of wind turbines with electrical and 848 operational years of turbines with hydraulic pitch system. Results of this study show high failure rates in pitch systems of both types, with hydraulic systems performing slightly better than electrical (0.54 vs. 0.56 failures per turbine per year), a significant variation between turbines of different manufacturers, and a tendency for higher failure rates for larger turbines.

AB - The pitch system is notably one of the critical subsystems of a wind turbine, supporting its effective control towards maximising wind capture and at the same time protecting its integrity in cases of excessive loads. A pitching mechanism is also responsible for operational downtime, hence its reliability performance needs to be carefully evaluated so as to ensure operational availability. This study aims to derive failure rates of two configurations of pitch systems, namely the electrical and hydraulic, based on statistical analysis of a large population of onshore assets, followed by a classification of findings by turbine rating, effect of seasonality, and reliability performance of different manufacturers. The data sets underlying the present analysis are based on maintenance reports and comprise 1847 operational years of wind turbines with electrical and 848 operational years of turbines with hydraulic pitch system. Results of this study show high failure rates in pitch systems of both types, with hydraulic systems performing slightly better than electrical (0.54 vs. 0.56 failures per turbine per year), a significant variation between turbines of different manufacturers, and a tendency for higher failure rates for larger turbines.

KW - Failure rate

KW - Field data

KW - Pitch system

KW - Reliability analysis

KW - Wind turbines

UR - http://www.scopus.com/inward/record.url?scp=85147925102&partnerID=8YFLogxK

U2 - 10.1016/j.egyr.2023.02.007

DO - 10.1016/j.egyr.2023.02.007

M3 - Article

AN - SCOPUS:85147925102

VL - 9

SP - 3273

EP - 3281

JO - Energy Reports

JF - Energy Reports

ER -