# US 9,518,562 B2 · Wind turbine generator having an eddy current brake, wind turbine having such a generator, and associated methods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,518,562 B2 - Document ID: US9518562B2 - Status: Granted - Kind: B2 - Application number: 14/438,428 - Filed: 2013-09-12 - Published: 2016-02-18 - Granted: 2016-12-13 - Earliest claimed: 2012-10-24 - Assignees: Vestas Wind Systems A/S - Applicants: Vestas Wind Systems A/S - Inventors: Peter Mongeau - Web page: https://patentgrep.com/patent/US9518562B2 ## CPC - F03D 80/60: Cooling or heating of wind motors - F03D 7/0244: {for braking} - F03D 9/25: the apparatus being an electrical generator (F03D9/22 takes precedence) - F03D 80/80: Arrangement of components within nacelles or towers - F03D 80/82: {of electrical components} - H02K 7/104: with eddy-current brakes - H02K 7/1838: {Generators mounted in a nacelle or similar structure of a horizontal axis wind turbine} - H02K 9/06: with fans or impellers driven by the machine shaft - H02K 9/08: by gaseous cooling medium circulating wholly within the machine casing (H02K9/10 takes precedence) - F05B 2260/903: using electrical or magnetic forces - Y02E 10/72: Wind turbines with rotation axis in wind direction - F03D: WIND MOTORS - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) - 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 ## Abstract A wind turbine generator includes an outer housing, a drive shaft rotatably mounted within the outer housing, stator and rotor assemblies positioned within the outer housing and movable relative to each other, a heat exchanger, and a blower having a rotating plate for generating a fluid flow circuit within the generator for transporting heat from the stator and rotor assemblies to the heat exchanger. An eddy current brake having a rotating member is located within the outer housing and is positioned in the fluid flow circuit such that fluid moving in the flow circuit cools the first rotating member. The blower and the eddy current brake may be integrated, such as by having the rotating plate of the blower serve as the rotating member of the eddy current brake. A wind turbine having such a generator, as well as a method of operating a wind turbine generator is also disclosed. ## Claims ### Claim 1 A wind turbine generator, comprising: an outer housing adapted to be positioned within the nacelle; a drive shaft rotatably mounted within the outer housing; a stator assembly positioned within the outer housing; a rotor assembly positioned within the outer housing, wherein the stator assembly is coupled to the outer housing so as to be stationary and the rotor assembly is operatively coupled to the drive shaft so as to be rotated with rotation of the drive shaft; a heat exchanger for removing heat from the generator; a blower positioned within the outer housing, the blower generating a first fluid flow circuit within the generator configured to transport heat from at least one of the stator and rotor assemblies to the heat exchanger, the blower including a first rotating plate; and a first eddy current brake positioned within the outer housing, the first eddy current brake including a first rotating member, wherein the first rotating member of the first eddy current brake is positioned in the first fluid flow circuit established by the blower such that fluid moving in the first fluid flow circuit passes over the first rotating member so as to cool the first rotating member. ### Claim 2 (depends on 1) The wind turbine generator according to claim 1, wherein the first eddy current brake is integrated with the blower. ### Claim 3 (depends on 2) The wind turbine generator according to claim 2, wherein the first rotating plate of the blower operates as the first rotating member of the first eddy current brake. ### Claim 4 (depends on 1) The wind turbine generator according to claim 1, wherein the first eddy current brake further includes a first magnet assembly including a plurality of electromagnetic modules positioned in close proximity to the first rotating member, the generator further including a controller for controlling the current to the electromagnetic modules so as to control the braking provided by the first eddy current brake. ### Claim 5 (depends on 1) The wind turbine generator according to claim 1, comprising a second eddy current brake positioned within the outer housing, the second eddy current brake including a second rotating member, wherein the second rotating member of the second eddy current brake is positioned in the first fluid flow circuit established by the blower such that fluid moving in the first fluid flow circuit passes over the second rotating member so as to cool the second rotating member. ### Claim 6 (depends on 5) The wind turbine generator according to claim 5, wherein the second eddy current brake is integrated with a blower. ### Claim 7 (depends on 5) The wind turbine generator according to claim 5, wherein the first eddy current brake is integrated with the blower and, wherein the second eddy current brake is integrated with the same blower that is integrated with the first eddy current brake. ### Claim 8 (depends on 7) The wind turbine generator according to claim 7, wherein the blower includes a second rotating plate, the second rotating plate of the blower operating as the second rotating member of the second eddy current brake. ### Claim 9 (depends on 5) The wind turbine generator according to claim 5, wherein the second eddy current brake further includes a second magnet assembly including a plurality of electromagnetic modules positioned in close proximity to the second rotating member, the generator further including a controller for controlling the current to the electromagnetic modules so as to control the braking provided by the second eddy current brake. ### Claim 10 (depends on 1) The wind turbine generator according to claim 1, further comprising a second fluid flow circuit, the second fluid flow circuit flowing through the heat exchanger and configured to remove heat from the first fluid flow circuit and transfer the heat away from the generator. ### Claim 11 (depends on 10) The wind turbine generator according to claim 10, wherein the heat exchanger includes a plurality of conduits extending therethrough configured to carry the fluid from the first fluid flow circuit and maintain the fluid of the first fluid flow circuit isolated from the fluid of the second fluid flow circuit. ### Claim 12 (depends on 10) The wind turbine generator according to claim 10, wherein the rotor assembly includes a plurality of passageways extending along a length thereof configured to carry the fluid from the first fluid flow circuit. ### Claim 13 (depends on 1) The wind turbine generator according to claim 1, wherein the heat exchanger is configured as a water jacket. ### Claim 14 A wind turbine, comprising: a tower; a nacelle disposed adjacent a top of the tower; a rotor including a hub and at least one wind turbine blade extending from the hub; and a generator disposed in the nacelle, comprising: an outer housing; a drive shaft rotatably mounted within the outer housing; a stator assembly positioned within the outer housing; a rotor assembly positioned within the outer housing, wherein the stator assembly is coupled to the outer housing so as to be stationary and the rotor assembly is operatively coupled to the drive shaft so as to be rotated with rotation of the drive shaft; a heat exchanger for removing heat from the generator; a blower positioned within the outer housing, the blower generating a first fluid flow circuit within the generator configured to transport heat from at least one of the stator and rotor assemblies to the heat exchanger, the blower including a first rotating plate; and a first eddy current brake positioned within the outer housing, the first eddy current brake including a first rotating member, wherein the first rotating member of the first eddy current brake is positioned in the first fluid flow circuit established by the blower such that fluid moving in the first fluid flow circuit passes over the first rotating member so as to cool the first rotating member. ### Claim 15 A method of operating a wind turbine generator having an outer housing, a drive shaft rotatably mounted within the outer housing, a stator assembly positioned within the outer housing, a rotor assembly positioned within the outer housing, and a heat exchanger, comprising: driving the drive shaft of the generator using a rotor of a wind turbine; rotating the rotor assembly relative to the stator assembly to generate electricity; establishing within the outer housing a first fluid flow circuit configured to transport heat to the heat exchanger, the first fluid flow circuit being established by a blower having a first rotating plate; positioning a first eddy current brake within the outer housing such that a first rotating member of the first eddy current brake is positioned in the first fluid flow circuit; using the first eddy current brake to apply a braking force; and cooling the first rotating member by passing fluid moving in the first fluid flow circuit over the first rotating member. ### Claim 16 (depends on 15) The method according to claim 15, further comprising integrating the first eddy current brake into the blower. ### Claim 17 (depends on 16) The method according to claim 16, further comprising using the first rotating plate of the blower as the rotating member of the first eddy current brake. ### Claim 18 (depends on 15) The method according to claim 15, further comprising: providing a second eddy current brake positioned within the outer housing having a second rotating member; and positioning the second rotating member in the first fluid flow circuit; and cooling the second rotating member by passing fluid moving in the first fluid flow circuit over the second rotating member. ### Claim 19 (depends on 18) The method according to claim 18, further comprising integrating the second eddy current brake into a blower. ### Claim 20 (depends on 15) The method according to claim 15, further comprising using a second fluid flow circuit to remove heat from the first fluid flow circuit and away from the generator. ### Claim 21 (depends on 14) The method according to claim 14, wherein the nacelle includes a nacelle housing, and the generator is disposed in the nacelle housing.