Humidity in Power Converters of Wind Turbines— Field Conditions and Their Relation with Failures

Energies

Michael Steffes¹  Martin Dörenkämper²  Katharina Fischer³  Bernd Tegtmeier³  Karoline Pelka³ 

[1] ConverterTec Deutschland GmbH, 47906 Kempen, Germany;Fraunhofer Institute for Wind Energy Systems IWES, 26129 Oldenburg, Germany;Fraunhofer Institute for Wind Energy Systems IWES, 30159 Hannover, Germany;

关键词: converter;    power electronics;    wind turbines;    failure;    environmental impact;    climatic conditions;   

DOI  :  10.3390/en14071919

来源: DOAJ

【 摘 要 】

Power converters in wind turbines exhibit frequent failures, the causes of which have remained unexplained for years. Field-experience based research has revealed that power- and thermal-cycling induced fatigue effects in power electronics do not contribute significantly to the field failures observed. Instead, clear seasonal failure patterns point to environmental influences, in particular to humidity, as a critical stressor and likely driver of converter failure. In addition to the electrical operating conditions, it is therefore important to also identify and characterize the climatic conditions that power converters in wind turbines are exposed to, both as a contribution to root-cause analysis and as a basis for the derivation of suitable test procedures for reliability qualification of components and systems. This paper summarizes the results of field-measurement campaigns in 31 wind turbines of seven different manufacturers spread over three continents. The temperature and humidity conditions inside the converter cabinets are characterized and related to the environmental conditions of the turbines and to their operation. The cabinet-internal climate is found to be subject to pronounced seasonal variations. In addition to the site-specific ambient climatic conditions and the operation of the turbines, the converter cooling concept is identified to significantly influence the climatic conditions inside the power cabinets.

【 授权许可】

Unknown