Reliability Analysis of Wind Turbine Blades Based on Numerical Analysis and Multi-fault Competition Failure

Due to the complexity of wind turbine blade operating environment and load form, its failure is often caused by the interaction of its own performance degradation and external impact. A wind turbine blade reliability analysis method considering multi-failure mode competition failure is proposed for the diverse characteristics of wind turbine blade failure types and degradation states. The mechanism of degradation failure and sudden failure and the competition failure process are analyzed, and the wind turbine blade reliability analysis system considering multi-failure mode competition failure is constructed on the basis of hypothesis testing. A nonlinear Wiener process with random effects is used to establish the performance degradation trajectory of the product, a Weibull distribution is introduced to describe the sudden failure model with random failure times, and a competing failure reliability model is further established on the basis of considering the independence and correlation of the two, and parameter estimation is performed. In order to verify the effectiveness of the method, a wind turbine blade is used as the research object, and the fatigue crack expansion simulation test is carried out with the finite element analysis software to obtain the crack expansion increment data set, which is used for the analysis of the calculation cases. The results show that the reliability analysis method considering the competing failure of both under the relevant conditions can objectively describe the reliability change law of wind turbine blade. The research results can provide theoretical support for wind turbine blade reliability design and low-cost and long-term operation and maintenance of wind farms.