A method for calculating fatigue strength of a wind turbine cabin structure

Abstract

The invention belongs to the technical field of wind turbine cabin structure fatigue strength calculation, and particularly relates to a method for calculating fatigue strength of a wind turbine cabinstructure. The objective of the invention is to make wind turbine cabin structure fatigue checking more accurate and reliable, overcome incomplete consideration of fatigue strength influence factorsin a previous calculation process, and inaccuracy of fatigue damage calculation. A unit load component and a generator gravity working condition stress result are obtained through a finite element analysis method, a stress time sequence is obtained in combination with a fatigue time sequence, a stress spectrum is obtained through a rain flow counting method, and then S-N curve cluster of the material under different stress ratios is established. And finally, the final damage is calculated by adopting a Miner linear cumulative damage theory. The method is characterized by comprising the following steps: determining a stress spectrum; Calculating S-under different stress ratios of material An N-curve family; checking the Cabin structure fatigue strength. The method is more accurate and moresuitable for actual load working conditions, fatigue damage of the cabin structure of the wind turbine can be more accurately analyzed, and the operation safety and reliability of wind turbine generator equipment are improved.

Description

technical field [0001] The invention belongs to the technical field of fatigue strength calculation of a wind turbine nacelle structure, and in particular relates to a calculation method for the fatigue strength of a wind turbine nacelle structure. Background technique [0002] The nacelle structure is one of the most critical and complex components in the permanent magnet direct drive wind turbine, and its design reliability directly affects the safety of the unit's operation. Among the hundreds of wind power accidents at home and abroad in the past ten years, most of them were caused by fatigue damage. The design life of wind turbines is usually 20 years. During the design life, they must bear the alternating stress generated by alternating loads and possible fatigue damage. Therefore, a scientific and standardized calculation and calibration must be done for the safety and reliability of wind turbines. nuclear. [0003] In the past, when the fatigue strength analysis of...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to make the fatigue check of the wind turbine nacelle structure more accurate and reliable, to overcome the problems of incomplete consideration of fatigue strength influence factors and inaccurate calculation of fatigue damage in the previous calculation process, and to obtain the unit load component and the gravity of the generator through the finite element analysis method The stress results under load are combined with the fatigue time series to obtain the stress time series, and then the stress spectrum is obtained through the rainflow counting method, and then the S-N curve family under different stress ratios of the material is established, and finally the final damage is calculated using the Miner linear cumulative damage theory

Images