Performance and application of pultrusion-processed fibre-reinforced composites in large-scale wind turbine blades

Pultruded composite materials have broad application prospects in the field of wind power generation. In this study, we explored the application of three different pultruded composites for the spar caps of wind turbine blades. Through comprehensive morphological, thermal, and mechanical analyses, as well as static and fatigue loading tests, we assessed the properties of these composites. Notably, the pultruded composites demonstrated high modulus, adequate strength, and excellent fatigue resistance. Among them, the optimal composite had an elastic modulus that was 46.4% higher than that of an E-glass vacuum-assisted resin-infused laminate. To further investigate their viability, we constructed a finite element model for a wind turbine blade with a pultruded composite spar cap using ANSYS. The results indicated that in a 94-m blade, replacing the E-glass vacuum-assisted resin-infused blade spar cap with the pultruded composite would result in a substantial 32.5% weight reduction. Finally, a 94-m blade was prototyped and tested, confirming its compliance with static and fatigue loading requirements. This study contributes to the advancement of composite materials and manufacturing methods for large-scale wind turbine blades.