# US 12,014,870 B2 · Air-core reactors for use with power transmission systems > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,014,870 B2 - Document ID: US12014870B2 - Status: Granted - Kind: B2 - Application number: 17/720,160 - Filed: 2022-04-13 - Published: 2023-10-19 - Granted: 2024-06-18 - Earliest claimed: 2022-04-13 - Assignees: GE Infrastructure Technology LLC - Applicants: General Electric Technology GmbH - Inventors: Amit Kumar; Henrique Borges Zaninelli; Luiz Souza - Web page: https://patentgrep.com/patent/US12014870B2 ## CPC - H01F 7/16: Rectilinearly-movable armatures (H01F7/17 takes precedence) - H01F 37/005: {without magnetic core} - H01F 7/081: {Magnetic constructions} - H01F 7/127: Assembling - H01F 27/28: Coils; Windings; Conductive connections - H01F 27/385: {for reducing harmonics} - H01F 7/134: {Actuators with two coils} - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES ## Abstract Air-core reactors for use with power transmission systems are disclosed. An example air-core reactor may include a main coil and an auxiliary coil. The main coil may include a first solenoid having a first diameter and a second solenoid having a second diameter, wherein the first diameter and the second diameter are different. The auxiliary coil may include a third solenoid. The first solenoid and the second solenoid may be arranged concentrically. The auxiliary coil may also be magnetically coupled to the main coil, and the auxiliary coil may be arranged concentric to the main coil. ## Claims ### Claim 1 An air-core reactor comprising: a main coil electrically connected to a main circuit of a power transmission system, the main coil comprising: a first solenoid having a first diameter; and a second solenoid having a second diameter, wherein the first diameter and the second diameter are different; and an auxiliary coil comprising a third solenoid, wherein the auxiliary coil is electrically connected to an auxiliary circuit of the power transmission system, wherein the main circuit is connected to first devices, wherein the auxiliary circuit is connected to lower power devices than the first devices, wherein the first solenoid and the second solenoid are arranged concentrically, wherein the auxiliary coil is magnetically coupled to the main coil, and wherein the auxiliary coil is arranged concentric to the main coil. ### Claim 2 (depends on 1) The air-core reactor of claim 1, wherein the main coil further comprises: a fourth solenoid having a third diameter, wherein the first diameter, the second diameter, and the third diameter are different. ### Claim 3 (depends on 2) The air-core reactor of claim 2, wherein the first solenoid, the second solenoid, and the fourth solenoid are arranged concentrically. ### Claim 4 (depends on 1) The air-core reactor of claim 1, wherein the auxiliary circuit comprises a band-pass filter configured to provide harmonic damping to a voltage source converter that is electrically connected to the main circuit of the power transmission system. ### Claim 5 (depends on 1) The air-core reactor of claim 1, wherein the auxiliary circuit comprises an LC circuit connected across a main circuit breaker. ### Claim 6 (depends on 1) The air-core reactor of claim 1, wherein the auxiliary coil is electrically isolated from the main coil. ### Claim 7 (depends on 1) The air-core reactor of claim 1, wherein the lower power devices are electrically isolated from the main coil. ### Claim 8 A system comprising: a power transmission system, the power transmission system comprising an air-core reactor comprising: a main coil electrically connected to a main circuit of a power transmission system, the main coil comprising: a first solenoid having a first diameter; and a second solenoid having a second diameter, wherein the first diameter and the second diameter are different; and an auxiliary coil comprising a third solenoid, wherein the auxiliary coil is electrically connected to an auxiliary circuit of the power transmission system, wherein the main circuit is connected to first devices, wherein the auxiliary circuit is connected to lower power devices than the first devices, wherein the first solenoid and the second solenoid are arranged concentrically, wherein the auxiliary coil is magnetically coupled to the main coil, and wherein the auxiliary coil is arranged concentric to the main coil. ### Claim 9 (depends on 8) The system of claim 8, wherein the main coil further comprises: a fourth solenoid having a third diameter, wherein the first diameter, the second diameter, and the third diameter are different. ### Claim 10 (depends on 9) The system of claim 9, wherein the first solenoid, the second solenoid, and the fourth solenoid are arranged concentrically. ### Claim 11 (depends on 8) The system of claim 8, wherein the auxiliary circuit comprises a band-pass filter configured to provide harmonic damping to a voltage source converter that is electrically connected to the main circuit of the power transmission system. ### Claim 12 (depends on 8) The system of claim 8, wherein the auxiliary coil is electrically isolated from the main coil. ### Claim 13 (depends on 8) The system of claim 8, wherein the lower power devices are electrically isolated from the main coil. ### Claim 14 A method of implementing an air-core reactor in a power transmission system, comprising: arranging a first solenoid having a first diameter concentric to a second solenoid having a second diameter; disposing an auxiliary coil comprising a third solenoid within a main coil, wherein the main coil comprises the first solenoid and the second solenoid, and wherein the auxiliary coil is magnetically coupled to the main coil; electrically connecting the main coil to a main circuit of the power transmission system; and electrically connecting the auxiliary coil to an auxiliary circuit of the power transmission system, wherein the auxiliary coil is electrically connected to an auxiliary circuit of the power transmission system, wherein the main circuit is connected to first devices, and wherein the auxiliary circuit is connected to lower power devices than the first devices. ### Claim 15 (depends on 14) The method of claim 14, wherein the main coil further comprises: a fourth solenoid having a third diameter, wherein the first diameter, the second diameter, and the third diameter are different. ### Claim 16 (depends on 15) The method of claim 15, wherein the first solenoid, the second solenoid, and the fourth solenoid are arranged concentrically. ### Claim 17 (depends on 14) The method of claim 14, wherein the auxiliary circuit comprises a band-pass filter configured to provide harmonic damping to a voltage source converter that is electrically connected to the main circuit of the power transmission system. ### Claim 18 (depends on 14) The method of claim 14, wherein the auxiliary coil is electrically isolated from the main coil. ### Claim 19 (depends on 14) The method of claim 14, wherein the lower power devices are electrically isolated from the main coil.