# US 9,518,558 B2 · Efficient wind turbine blades, wind turbine blade structures, and associated systems and methods of manufacture, assembly and use > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,518,558 B2 - Document ID: US9518558B2 - Status: Granted - Kind: B2 - Application number: 13/951,727 - Filed: 2013-07-26 - Published: 2014-06-05 - Granted: 2016-12-13 - Earliest claimed: 2008-12-05 - Assignees: Vestas Wind Systems A/S - Applicants: Vestas Wind Systems A/S - Inventors: Myles L. Baker; Cory P. Arendt; Bernard G. Madrid; Sheldon Vilhauer - Web page: https://patentgrep.com/patent/US9518558B2 ## CPC - F03D 1/0675: {of the blades} - B29C 70/304: {In-plane lamination by juxtaposing or interleaving of plies, e.g. scarf joining} - F03D 13/10: Assembly of wind motors; Arrangements for erecting wind motors - B29D 99/0028: {hollow blades} - B29L 2031/085: {Wind turbine blades} - F05B 2240/30: Characteristics of rotor blades, i.e. of any element transforming dynamic fluid energy to or from rotational energy and being attached to a rotor - F05B 2240/302: Segmented or sectional blades - Y02E 10/72: Wind turbines with rotation axis in wind direction - Y02E 10/74: Wind turbines with rotation axis perpendicular to the wind direction - Y02P 70/50: Manufacturing or production processes characterised by the final manufactured product - Y10T 29/49316: Impeller making - Y10T 29/49337: Composite blade - Y10T 29/49339: Hollow blade - Y10T 156/10: Methods of surface bonding and/or assembly therefor - F03D: WIND MOTORS - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - B29D: PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE (making granules B29B9/00; making preforms B29B11/00) - B29L: INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES - F05B: INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract Wind turbine systems and methods are disclosed herein. A representative system includes a wind turbine blade having an inner region that has an internal load-bearing truss structure, and an outer region that has an internal, non-truss, load-bearing structure. In particular embodiments, the truss structure can include a triangular arrangement of spars, and/or can include truss attachment members that connect components of the truss without the use of holes in the spars. Spars can be produced from a plurality of pultruded composite members laminated together in longitudinally extending portions. The longitudinally extending portions can be connected at joints that interleave projections and recesses of each of the spar portions. The blades can include fan-shaped transitions at a hub attachment portion, formed by laminated layers and/or a combination of laminated layers and transition plates. ## Claims ### Claim 1 A wind turbine blade, comprising: an external aerodynamic surface having a longitudinally-extending spanwise axis, a chordwise axis extending transverse to the spanwise axis, and a thickness axis extending transverse to both the chordwise and spanwise axes; and a plurality of longitudinally-extending spars providing internal support for the aerodynamic surface, wherein at least one of the spars includes a laminate of precured composite material, the laminate of precured composite material including: a plurality of precured, pultruded composite layers, wherein each of the pultruded composite layers overlaps with the others in the at least one spar at at least one longitudinal location; and a plurality of adhesive layers interposed between adjacent precured, pultruded composite layers. ### Claim 2 (depends on 1) The wind turbine blade of claim 1 wherein each of the precured, pultruded composite layers includes a precured fiber-reinforced resin product. ### Claim 3 (depends on 1) The wind turbine blade of claim 1 wherein the aerodynamic surface defines an airfoil cross-section, wherein the plurality of longitudinally-extending spars include a pressure spar and a suction spar spaced apart from each other along the thickness axis, and an aft spar spaced apart from both the pressure and suction spars along the chordwise axis, and wherein each of the pressure, suction and aft spars are comprised of a laminate of precured composite pultrusions. ### Claim 4 (depends on 1) The wind turbine blade of claim 1, further comprising a plurality of longitudinally spaced-apart ribs, and wherein the at least one spar is attached to the ribs. ### Claim 5 (depends on 1) The wind turbine blade of claim 1, further comprising a strap clamped circumferentially around the plurality of precured, pultruded composite layers. ### Claim 6 (depends on 1) The wind turbine blade of claim 1, further comprising: a plurality of longitudinally spaced-apart ribs; and a plurality of truss attachment members, wherein each of the truss attachment members includes a first piece and a corresponding second piece, wherein each of the first pieces is attached to the corresponding second piece to clamp a portion of the precured composite layers together therebetween, and wherein at least one of the first piece and the second piece of each truss attachment member is attached to one of the longitudinally spaced apart ribs. ### Claim 7 (depends on 1) The wind turbine blade of claim 1 wherein the at least one spar tapers in at least an outboard direction, and wherein the taper results from precured, pultruded composite layers terminating at different longitudinal locations. ### Claim 8 (depends on 1) The wind turbine blade of claim 1 wherein individual precured, pultruded composite layers terminate at different longitudinal locations. ### Claim 9 (depends on 1) The wind turbine blade of claim 1 wherein individual precured, pultruded composite layers terminate at different longitudinal locations, and wherein the terminations are chamfered. ### Claim 10 (depends on 1) The wind turbine blade of claim 1 wherein individual precured, pultruded composite layers have a chordwise extent and a thickness extent less than the chordwise extent. ### Claim 11 (depends on 1) The wind turbine blade of claim 1 wherein individual precured, pultruded composite layers are flat along the chordwise axis. ### Claim 12 (depends on 1) The wind turbine blade of claim 1 wherein individual precured, pultruded composite layers are formed separately from the external aerodynamic surface. ### Claim 13 (depends on 1) The wind turbine blade of claim 1 wherein inner and outer surfaces of the at least one spar are generally parallel to a mean slope of the local external aerodynamic surface. ### Claim 14 (depends on 13) The wind turbine blade of claim 13 wherein the inner and outer surfaces of the at least one spar are generally flat and wherein the local external aerodynamic surface is curved. ### Claim 15 A wind turbine blade, comprising: an external aerodynamic surface having a longitudinally-extending spanwise axis, a chordwise axis extending transverse to the spanwise axis, and a thickness axis extending transverse to both the chordwise and spanwise axes; and a plurality of longitudinally-extending spars providing internal support for the aerodynamic surface, wherein at least one of the spars has inner and outer surfaces that are generally flat and wherein the local external aerodynamic surface is curved, further wherein the at least one spar includes a laminate of precured composite material, the laminate of precured composite material including: a plurality of precured, pultruded composite layers, wherein each of the pultruded composite layers overlaps with the others in the at least one spar at at least one longitudinal location, and wherein individual precured, pultruded composite layers have a chordwise extent and a thickness extent less than the chordwise extent; and a plurality of adhesive layers interposed between adjacent precured, pultruded composite layers. ### Claim 16 (depends on 15) The wind turbine blade of claim 15 wherein individual precured, pultruded composite layers terminate at different longitudinal locations. ### Claim 17 (depends on 16) The wind turbine blade of claim 16 wherein the terminations are chamfered. ### Claim 18 (depends on 17) The wind turbine blade of claim 17 wherein the terminations are staggered to form a tapered shape along the longitudinal axis.