# US 12,604,381 B2 · Boost-based power factor correction with closed-loop control > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,604,381 B2 - Document ID: US12604381B2 - Status: Granted - Kind: B2 - Application number: 18/441,799 - Filed: 2024-02-14 - Published: 2025-08-14 - Granted: 2026-04-14 - Earliest claimed: 2024-02-14 - Assignees: Honeywell International Inc. - Applicants: Honeywell International Inc. - Inventors: Deepak B. Mahajan; Abhijit Kulkarni; Ritu Rai; Nipun Kumar Chawda - Web page: https://patentgrep.com/patent/US12604381B2 ## CPC - H05B 45/355: Power factor correction [PFC]; Reactive power compensation - H02M 1/4225: {using a non-isolated boost converter} - H05B 45/3725: Switched mode power supply [SMPS] - H05B 45/375: using buck topology - H05B 45/38: using boost topology - H05B 45/385: using flyback topology - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) ## Abstract Boost-based power factor correction with closed-loop control is described herein. Some embodiments include a current-source fed power factor correction circuit, comprising a current transformer configured to step down a current from a current source, a diode bridge rectifier connected to the current transformer, a capacitor connected to an output of the diode bridge rectifier, a boost converter having a start-up diode and connected to the capacitor, a direct current (DC)-DC converter connected to an output of the boost converter and configured to regulate an operation of a light-emitting diode (LED), a voltage sensor configured to determine output voltage, and a current sensor configured to determine a current associated with the diode bridge rectifier. ## Claims ### Claim 1 A current-source fed power factor correction circuit, comprising: a current transformer configured to step down a current from a current source; a diode bridge rectifier connected to the current transformer; a capacitor connected to an output of the diode bridge rectifier; a boost converter having a start-up diode and connected to the capacitor; a direct current (DC)-DC converter connected to an output of the boost converter and configured to regulate an operation of a light-emitting diode (LED); a voltage sensor configured to determine output voltage; and a current sensor configured to determine a current associated with the diode bridge rectifier, wherein the current transformer, the capacitor, and a boost inductor of the boost converter act as a latching current limiter (LCL) filter. ### Claim 2 (depends on 1) The circuit of claim 1, wherein the output voltage activates a plurality of LEDs. ### Claim 3 (depends on 2) The circuit of claim 2, wherein the plurality of LEDs are airport runway lights or airport taxiway lights. ### Claim 4 (depends on 1) The circuit of claim 1, wherein an off-time duty ratio of the circuit is given by: d ′ = 2 ⁢ P η ⁢ k ct ⁢ i rms ⁢ V o ⁢ ❘ "\[LeftBracketingBar]" sin ⁡ ( ω ⁢ t ) ❘ "\[RightBracketingBar]" , wherein: P is a total output power; irms is an input rms current; Vo is a desired output voltage; Kct is a turns ratio of the current transformer; η is efficiency; and ω corresponds to a frequency of the current source. ### Claim 5 (depends on 1) The circuit of claim 1, wherein the voltage sensor is a resistor divider network. ### Claim 6 (depends on 1) The circuit of claim 1, wherein the capacitor is a ceramic capacitor. ### Claim 7 (depends on 1) The circuit of claim 1, wherein the current source is a phase-cut current source. ### Claim 8 (depends on 1) The circuit of claim 1, wherein the LCL filter is configured to attenuate switching harmonic voltages appearing at the current source. ### Claim 9 (depends on 1) The circuit of claim 1, wherein the circuit comprises exclusively analog components. ### Claim 10 A system, comprising: a plurality of light-emitting diodes (LEDs); and a current-source fed power factor correction circuit, comprising: a current transformer configured to step down a current from a current source; a diode bridge rectifier connected to the current transformer; a capacitor connected to an output of the diode bridge rectifier; a boost converter having a start-up diode and connected to the capacitor; a direct current (DC)-DC converter connected to an output of the boost converter and configured to regulate an operation of the plurality of LEDs; a voltage sensor configured to determine output voltage; and a current sensor configured to determine a current associated with the diode bridge rectifier, wherein the current transformer, the capacitor, and a boost inductor of the boost converter act as a latching current limiter (LCL) filter. ### Claim 11 (depends on 10) The system of claim 10, wherein the plurality of LEDs are airport runway lights. ### Claim 12 (depends on 10) The system of claim 10, wherein the plurality of LEDs are airport taxiway lights. ### Claim 13 (depends on 10) The system of claim 10, wherein each of the plurality of LEDs has a power rating exceeding 70 watts. ### Claim 14 A method, comprising: connecting a circuit to a current source, the circuit comprising: a current transformer configured to step down a current from the current source; a diode bridge rectifier connected to the current transformer; a capacitor connected to an output of the diode bridge rectifier; a boost converter having a start-up diode and connected to the capacitor; a direct current (DC)-DC converter connected to an output of the boost converter and configured to regulate an operation of a string of light-emitting diodes (LEDs); a voltage sensor configured to determine output voltage; and a current sensor configured to determine a current associated with the diode bridge rectifier, wherein the current transformer, the capacitor, and a boost inductor of the boost converter act as a latching current limiter (LCL) filter; charging the capacitor via the start-up diode; activating the string of LEDs responsive to a boost output voltage exceeding a string voltage associated with the string of LEDs. ### Claim 15 (depends on 14) The method of claim 14, wherein the method includes regulating the boost output voltage to a known value. ### Claim 16 (depends on 14) The method of claim 14, wherein the circuit comprises exclusively analog components. ### Claim 17 (depends on 14) The method of claim 14, wherein the method includes tracking a reference voltage. ### Claim 18 (depends on 17) The method of claim 17, wherein the method includes comparing the reference voltage with a feedback voltage determined by the voltage sensor. ### Claim 19 (depends on 18) The method of claim 18, wherein the method includes determining a gain based on the output voltage and the feedback voltage.