Skip Navigation Links.

Search for publications:

Limit search to the fields

ECN publication
Betrouwbaarheidsanalyse NedWind 40
Published by: Publication date:
ECN 1996
ECN report number: Document type:
ECN-C--96-051 ECN publication
Number of pages: Full text:
39 Download PDF  

The experiences with reliability analysis techniques are presented forthe case study: 'NedWind 40: Reliability Analysis and Maintenance Procedures'. Also methods to collect failure and maintenance data are discussed. The reliability analysis techniques are described only briefly because they were performed in accordance with the practical guidelines for the assessment of wind turbine safety, as drafted in the Joule-II project 'European Wind Turbine Standards'. The analysis showed that these guidelines are suitable to obtain good results. The analysis procedure comprises the following steps: (1) description of the wind turbine, its main systems, and the operational procedures; (2) performance of event sequence analysis; (3) performance of Failure Modes, Effects, and Criticality Analysis (FMECA); (4) system modelling; and (5) quantification of system model and event sequences. The analysis revealed that performing the FMECA is the crucial step in reliability analysis. Because of this fact, NedWind wants to implement the FMECA in their 'design reviews' of new wind turbines. The analysis gives a lot of additional insight in the failure behaviour of the systems. The quantitative part of the reliability analysis was performed successfully with generic data from handbooks instead of specific wind turbine failure data, because the operational experience of the NedWind 40 was too short. Furthermore, the maintenance sheets did not contain all the information that was needed for a detailed quantitative analysis. The quantitative analysis showed that the NedWind 40 is a reliable and safe wind turbine. A general conclusion is that the availability of control and protection systems can be improved by applying monitoring, rather then applying components, with a higher reliability. In order to collect the necessary failure and maintenance data, a failure registration sheet was developed, together with a database structure for data storage. Analysis techniques for the failure and maintenance data were discussed briefly. 2 figs., 8 tabs.

Back to List