A wind turbine blade with an improved lightning protecting system

A wind turbine blade with a lightning protection system, comprising:

• a pressure side and a suction side, and a leading edge and a trailing edge with a chord having a chord length extending between the leading and trailing edges;
• a root end and a tip end, the wind turbine blade extending in a spanwise direction between the root end and the tip end;
• the lightning protection system comprising:
• at least one lightning receptor arranged at an outer surface of the blade;
• a first carbon fibre reinforced spar cap extending substantially in the spanwise direction of the wind turbine blade and having a chamfered tip end and an opposing chamfered root end, the first spar cap arranged inside the blade along the pressure side;
• a second carbon fibre reinforced spar cap extending substantially in the spanwise direction of the wind turbine blade and having a chamfered tip end and an opposing chamfered root end, the second spar cap arranged inside the blade along the suction side;
• and
• an electric connection between the at least one lightning receptor and the chamfered tip end or the chamfered root end of one of the first carbon fibre reinforced spar cap or the second carbon fibre reinforced spar cap, the electric connection comprising a conductive fabric having unidirectional carbon fibres bonded by an adhesive, the conductive fabric comprising a thickness of 0.01-0.5 mm and a fibre volume fraction (FVF) of at least 50%.

A method of manufacturing a shell half structure with a lightning protection system for a wind turbine blade having a pressure side and a suction side, and a leading edge and a trailing edge, the method comprising:

• arranging one or more first layers of fibre fabrics on a surface of a mould to form a first shell half structure,
• arranging one or more second layers of carbon fibres in a mould to form a spar cap having a chamfered tip end and an opposing chamfered root end,
• arranging at least one conductive fabric on at least part of the chamfered tip end or opposing chamfered root end of the spar cap, the conductive fabric having unidirectional carbon fibres bonded by an adhesive, a thickness of 0.05-0.3 mm, and a fibre volume fraction (FVF) of at least 50%;
• arranging a metallic mesh on at least part of the conductive fabric;
• and
• consolidating the one or more first layers of fibre fabrics, one or more second layers of carbon fibres, the conductive fabric, and the metallic mesh.