# US 12,215,672 B2 · Large inductors for lightning protection of power systems > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,215,672 B2 - Document ID: US12215672B2 - Status: Granted - Kind: B2 - Application number: 17/623,123 - Filed: 2020-06-24 - Published: 2022-07-21 - Granted: 2025-02-04 - Earliest claimed: 2019-06-26 - Assignees: Vestas Wind Systems A/S - Applicants: Vestas Wind Systems A/S - Inventors: Nathan A. Brilliant - Web page: https://patentgrep.com/patent/US12215672B2 ## CPC - F03D 80/30: Lightning protection - F03D 1/0675: {of the blades} - H02G 13/80: {Discharge by conduction or dissipation, e.g. rods, arresters, spark gaps} - Y02E 10/72: Wind turbines with rotation axis in wind direction - F03D: WIND MOTORS - H02G: INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract Embodiments herein describe a discharge filter, located in a root of a wind turbine blade, which includes one or more cables wound into large scale inductors using an internal or external surface of the root as a mandrel. These cables provide power inputs to an electrical panel for one or more a powered systems that are located in a body of the wind turbine blade. The electrical panel is connected to a lightning protection system that selectively provides a path to ground, and the inductors form a high-impedance barrier that shunts power away from the cables and onto the lightning protection system in the event of a lightning strike or other electrical discharge traveling from the powered systems to the electrical panel. ## Claims ### Claim 1 A wind turbine blade, comprising: a discharge filter, located on a root of the wind turbine blade, including a first cable wound into a first inductor using the root as a mandrel; a powered system, located in a body of the wind turbine blade; and an electrical panel, located between the discharge filter and the powered system in the body of the wind turbine blade, wherein the first cable is configured to provide power to the powered system through the electrical panel. ### Claim 2 (depends on 1) The wind turbine blade of claim 1, wherein the mandrel is an exterior surface of the root. ### Claim 3 (depends on 1) The wind turbine blade of claim 1, wherein the mandrel is an interior surface of the root. ### Claim 4 (depends on 1) The wind turbine blade of claim 1, wherein the first inductor is at least partially embedded in a material comprising the root. ### Claim 5 (depends on 1) The wind turbine blade of claim 1, wherein the first cable is a bundled cable including a live line, a neutral line, and a protective earth line. ### Claim 6 (depends on 1) The wind turbine blade of claim 1, wherein the discharge filter further includes: a second cable wound into a second inductor using the root as a mandrel; and a third cable wound into a third inductor using the root as a mandrel. ### Claim 7 (depends on 1) The wind turbine blade of claim 1, wherein a pathway between the first cable and the powered system is linked via a surge protection device to a lightning protection system offering a lower impedance path to ground than the first cable. ### Claim 8 (depends on 1) The wind turbine blade of claim 1, wherein the electrical panel receives at an input: the first cable; a second cable and a third cable; wherein the discharge filter is located between a power source and the electrical panel in the root of the blade. ### Claim 9 (depends on 1) The wind turbine blade of claim 1, wherein the root is a hollow cylinder. ### Claim 10 (depends on 8) The wind turbine blade of claim 8, wherein the electrical panel further receives a fourth cable at the input, and the discharge filter further comprises: a fourth inductor, comprising a portion of the fourth cable wound around the root as a mandrel. ### Claim 11 (depends on 10) The wind turbine blade of claim 10, wherein the electrical panel further receives a fifth cable at the input, and the discharge filter further comprises: a fifth inductor, comprising a portion of the fifth cable wound around the root as a mandrel. ### Claim 12 (depends on 6) The wind turbine blade of claim 6, wherein the first cable, the second cable, and the third cable are included in a single bundled cable wound into a bundled inductor. ### Claim 13 (depends on 6) The wind turbine blade of claim 6, wherein the first inductor is intertwined with the second inductor. ### Claim 14 (depends on 6) The wind turbine blade of claim 6, wherein the first inductor, the second inductor, and the third inductor are wound sequentially about the root. ### Claim 15 A wind turbine, comprising: a plurality of blades, wherein each blade of the plurality of blades is electrically connected to a power source via rotatable contacts in a nacelle from which a root of the blade extends towards a tip of the blade, each blade comprising: a first cable, electrically connected to the power source via the nacelle, and wound into a first inductor supported by a diameter of the root and connected to an input of an electrical panel; and a powered system, connected to an output of the electrical panel via an electrical lead and located tipward of the electrical panel. ### Claim 16 (depends on 15) A wind turbine according to claim 15, comprising: a second cable, electrically connected to the power source via the nacelle, and wound into a second inductor supported by the diameter of the root and connected to the input of the electrical panel; and a third cable, electrically connected to protective earth via the nacelle, and wound into a third inductor supported by the diameter of the root and connected to the input of the electrical panel. ### Claim 17 (depends on 16) A wind turbine according to claim 16, comprising: a lighting protection system, that is electrically isolated from the first cable, the second cable, and the third cable in the blade, that is connected to ground via the nacelle, and that is selectively connected to the electrical panel, wherein when electrically connected to the electrical panel, the lightning protection system provides a lower impedance path to ground than the first cable, the second cable, and the third cable. ### Claim 18 A wind turbine blade, comprising: a discharge filter, located on a root of the wind turbine blade, including a first cable wound into a first inductor using the root as a mandrel; a powered system, located in a body of the wind turbine blade; and an electrical panel, located between the discharge filter and the powered system in the body of the wind turbine blade, wherein the first cable is configured to provide power to the powered system through the electrical panel; wherein the first inductor is at least partially embedded in a material comprising the root; wherein the first cable is a bundled cable including a live line, a neutral line, and a protective earth line. ### Claim 19 (depends on 18) The wind turbine blade of claim 18, wherein the discharge filter further includes: a second cable wound into a second inductor using the root as a mandrel; and a third cable wound into a third inductor using the root as a mandrel. ### Claim 20 (depends on 19) The wind turbine blade of claim 19, wherein a pathway between the first cable and the powered system is linked via a surge protection device to a lightning protection system offering a lower impedance path to ground than the first cable.