Research on Structural Failure Analysis and Strengthening Design of Offshore Wind Turbine Blades

Abstract

The existing blade protection mechanisms are highly dependent on the control system and its power supply. Safety of offshore wind turbines cannot be guaranteed under extreme weather when the control protection mechanisms fail. So far, not enough consideration has been given to the above problems in mechanical design for protecting wind turbine blades. In this paper, a reinforcing cable component (RCC) is proposed to improve the resistance ability of offshore wind turbine blades. The static model of the blades with reinforcing cable component was presented. The Finite Element (FE) simulation was performed for a 5 MW offshore wind turbine and load reduction effect of connection location for RCC was discussed according to the FE results. A static strain verification test was carried out. Simulation and test results indicate that the proposed reinforcing cable component effectively reduces the strain as well as the tip displacement of the blades. The proposed mechanical structure will help to enhance the survival ability of offshore wind turbine blades when the control protection system fails.

Keywords

• wind turbine blades
• steel cable connection
• wind load
• finite element method
• structural stress
• static load test