# US 9,882,368 B2 · Systems and methods to detect an electric arc and a lightning strike > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,882,368 B2 - Document ID: US9882368B2 - Status: Granted - Kind: B2 - Application number: 14/068,893 - Filed: 2013-10-31 - Published: 2015-04-30 - Granted: 2018-01-30 - Earliest claimed: 2013-10-31 - Assignees: General Electric Company - Applicants: General Electric Company - Inventors: Yaru Najem Mendez Hernandez - Web page: https://patentgrep.com/patent/US9882368B2 ## CPC - H02G 13/00: Installations of lightning conductors; Fastening thereof to supporting structure - F03D 80/30: Lightning protection - Y02E 10/72: Wind turbines with rotation axis in wind direction - H02G: INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES - F03D: WIND MOTORS - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract An electric arc detection system is presented. The electric arc detection system comprises a receiving antenna that receives electromagnetic radiation generated by an electric arc formed in an internal cavity of a non-conductive hollow structure, and a processing subsystem for determining an existence of the electric arc in the internal cavity based upon signals representative of the electromagnetic radiation. ## Claims ### Claim 1 An electric arc detection system, the system comprising: a receiving antenna that receives electromagnetic radiation generated by an electric arc formed in an internal cavity of a non-conductive hollow structure; and a processing subsystem for determining an existence of the electric arc in the internal cavity based upon signals representative of the electromagnetic radiation, wherein the receiving antenna comprises a directional antenna directed towards at least one potential electric arc location in the non-conductive hollow structure. ### Claim 2 (depends on 1) The electric arc detection system of claim 1, wherein the receiving antenna comprises a radio frequency receiving antenna. ### Claim 3 (depends on 2) The electric arc detection system of claim 2, wherein the electromagnetic radiation comprises radio frequency waves. ### Claim 4 (depends on 1) The electric arc detection system of claim 1, wherein the non-conductive hollow structure comprises a hollow structure used to form a wing, fuselage, or tail of an aircraft, a hollow structure used to form a radome for an antenna, or a wind turbine rotor blade. ### Claim 5 (depends on 1) The electric arc detection system of claim 1, wherein the non-conductive hollow structure comprises a blade having a root and a tip at opposite ends along a longitudinal axis, and wherein the receiving antenna is located inside or on the root of the blade. ### Claim 6 (depends on 5) The electric arc detection system of claim 5, wherein the blade is attached to a hub, and wherein the receiving antenna is located on or inside the hub. ### Claim 7 (depends on 5) The electric arc detection system of claim 5, wherein the receiving antenna is directed towards the tip of the blade. ### Claim 8 (depends on 1) The electric arc detection system of claim 1, the receiving antenna is polarized to align with an expected polarization of the electromagnetic radiation generated by the electric arc. ### Claim 9 (depends on 1) The electric arc detection system of claim 1, wherein the non-conductive hollow structure comprises a rotor blade of a wind turbine comprising a hub. ### Claim 10 (depends on 9) The electric arc detection system of claim 9, wherein the rotor blade comprises a root and a tip at opposite ends along a longitudinal axis, and wherein the receiving antenna is located inside the hub and inside the rotor blade in close proximity to the root of the rotor blade. ### Claim 11 (depends on 9) The electric arc detection system of claim 9, wherein the rotor blade comprises a root and a tip at opposite ends along a longitudinal axis, and wherein the receiving antenna is located inside the hub and on an outer or inner surface of the root of the rotor blade. ### Claim 12 (depends on 1) The electric arc detection system of claim 1, wherein the processing subsystem is configured to determine the condition of the non-conductive hollow structure by performing a method comprising: comparing an amplitude of the electromagnetic radiation with a determined threshold; and determining the existence of the electric arc based upon the comparison of the amplitude of the electromagnetic radiation with the determined threshold. ### Claim 13 (depends on 12) The electric arc detection system of claim 12, wherein the processing subsystem further detects an occurrence of the lightning strike on and within the non-conductive hollow structure based upon the determination of the existence of the electric arc in the internal cavity of the non-conductive hollow structure. ### Claim 14 (depends on 1) The electric arc detection system of claim 1, wherein the processing subsystem further determines the condition of the non-conductive hollow structure based upon the electromagnetic radiation and a determined threshold. ### Claim 15 (depends on 1) The electric arc detection system of claim 1, wherein the non-conductive hollow structure comprises a radome comprising a bottom structure, wherein the receiving antenna is located inside the bottom structure of the radome, and the receiving antenna is directed away from the bottom structure and towards the top of the radome. ### Claim 16 A wind turbine system, comprising: a wind turbine hub; a plurality of rotor blades, each of the plurality of rotor blades comprising a respective root and a respective tip at opposite sides along a respective longitudinal axis; a plurality of radio frequency antennas, each of the plurality of radio frequency antennas located inside the wind turbine hub and inside a root of a respective rotor blade of the plurality of rotor blades and positioned to receive radio frequency waves generated by one or more electric arcs in a respective internal cavity of the respective rotor blade; and a processing subsystem for determining an existence of the one or more electric arcs in the respective internal cavity of the plurality of rotor blades based upon the radio frequency waves. ### Claim 17 (depends on 16) The wind turbine system of claim 16, wherein the plurality of radio frequency antennas comprises directional antennas at least three of which are each respectively directed towards a respective tip of a respective rotor blade. ### Claim 18 A method, comprising: receiving signals representative of radio frequency waves from a radio frequency receiving antenna located inside a non-conductive hollow structure; comparing an amplitude of the signals representative of the radio frequency waves with a determined threshold; and determining an existence of an electric arc in an internal cavity of the non-conductive hollow structure based upon the comparison of the amplitude of the signals representative of the radio frequency waves with the determined threshold. ### Claim 19 (depends on 18) The method of claim 18, wherein the non-conductive hollow structure comprises a wind turbine.