海上风机的模糊关联失效模式及其影响分析

Fuzzy theory-based correlated FMEA of offshore wind turbines

海上风机属于多系统多功能的大型设备,且运行环境条件恶劣,进行可靠性分析时面临着系统失效模式复杂且相互之间存在相关性的问题,失效模式及其影响分析(FMEA)方法无法对系统的风险进行准确评估。在完成传统FMEA的基础上,找出风险优先数(RPN)较高的若干失效模式,并制定发生率、严重度和检测度的模糊评价术语集合,应用基于TOPSIS理论的模糊FMEA方法对这些典型失效模式进行评价。对于在模糊FMEA中风险程度接近的失效模式,结合模糊语境下的决策试验与实验评估法(DEMATEL)计算各失效模式的原因度、综合参照影响度和原因度得出主要失效模式的风险排序。将模糊关联FMEA方法应用于海上风机的风险评估,计算结果表明发电机与冷却设备对系统安全性影响最为显著。

Offshore wind turbines are large multi-systematic multi-functional devices that operate in harsh marine environments. It is difficult to perform reliability analysis of these devices owing to the complex system failure modes involved and the correlation among them,and system risk cannot be evaluated accurately by using the failure mode and effects analysis（ FMEA）. In this study,we employed FMEA to identify failure modes with higher risk priority numbers（ RPNs）. Based upon the Technique for Order Preference by Similarity to Ideal Solution（ TOPSIS） theory,a set of fuzzy evaluation terms including severity,occurrence,and detection was determined in order to employ fuzzy FMEA for assessing these typical failure modes. The decision-making and trial evaluation laboratory（ DEMATEL） method was used to calculate causal degrees of failure modes with approximate risk levels in fuzzy FMEA,and the main failure modes were ranked based on the results of influence degree and causal degree analyses. We then applied the fuzzy correlated FMEA method for risk assessment of offshore wind turbines. The calculation results show that the generator and the cooling device most significantly influence the system security.