Optimized spar cap structure for wind turbine blade

A spar cap according to any of the preceding claims, wherein the first spar cap layer (20a), the second spar cap layer (20b) and the first interlayer (30) each have a first surface area (20aa, 20ba, 30a) and an opposite second surface area (20ab, 20bb, 30b), wherein the first surface area (20aa, 20ba, 30a) of the first spar cap layer (20a), the second spar cap layer (20b) and the first interlayer (30) is defined by the width and length of the first spar cap layer (20a), the second spar cap layer (20b) or the first interlayer (30), respectively, and wherein the first surface area (30a) of the first interlayer (30) is in contact with the second surface area (20ab) of the first spar cap layer (20a) and the second surface area (30b) of the first interlayer (30) is in contact with the first surface area (20ba) of the second spar cap layer (20b).

A spar cap according to any of the preceding claims, wherein the first spar cap layer (20) further comprises a first secondary pre-cured fibre-reinforced element (21b) arranged adjacent to the first primary pre-cured fibre reinforced element (21a), such that a first side of the first primary pre-cured fibre-reinforced element (21a) defined by the thickness and length of the first primary pre-cured fibre-reinforced element (21a), is adjacent to a second side of the first secondary pre-cured fibre-reinforced element (21b), defined by the thickness and length of the first secondary pre-cured fibre-reinforced element (21b).

A spar cap according to any of the preceding claims, wherein the first primary interlayer area (31a) extends along a first part of the length of the first interlayer (30) and wherein the second primary interlayer area (32a) extends along a second part of the length of the first interlayer (30).

A spar cap according to any of the preceding claims, wherein the first primary interlayer area (31a) extends along a first part of the width of the first interlayer (30) and wherein the second primary interlayer area (32a) extends along a second part of the width of the first interlayer (30).

A spar cap according to any of the preceding claims, wherein the second primary interlayer area (32a) is surrounded by the first primary interlayer area (31a).

A spar cap according to any of the preceding claims, wherein the first primary interlayer area (31a) forms at least part of a perimeter of the first interlayer (30).

(canceled)

(canceled)

A spar cap according to any of the preceding claims, wherein first number of interlayer sheets and the second number of interlayer sheets are arranged adjacent to each other, such that adjacent edges of the interlayer sheets are contacted with each other or wherein the first number of interlayer sheets and the second number of interlayer sheets overlap each other in areas where they meet.

A spar cap according to any of the preceding claims, wherein the first plurality of fibres (35) comprises polymeric filaments, such as polyester filaments, preferably thermoplastic polyester filaments or polypropylene filaments or polyethylene filaments.

A spar cap according to any of the preceding claims, wherein the second plurality of fibres (36) comprises glass fibres and/or carbon fibres.

(canceled)

A spar cap according to any of the preceding claims, wherein the first and/or second number of interlayer sheets (33, 34) are veils comprising randomly oriented fibres.

A spar cap according to any of the preceding claims, wherein the first and/or second number of interlayer sheets (33, 34) are nets, comprising woven fibres.

(canceled)

A spar cap according to any of the preceding claims, wherein the first number of interlayer sheets (33) are polyester veils and the second number of interlayer sheets (34) are bidirectional glass-fibre fabrics.

A spar cap according to any of the preceding claims, wherein each of the plurality of pre-cured fibre reinforced elements (21, 22) are pultruded carbon fibre reinforced plastic planks.

(canceled)