# US 11,121,633 B2 · Low common mode noise transformers and switch-mode DC-DC power converters > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,121,633 B2 - Document ID: US11121633B2 - Status: Granted - Kind: B2 - Application number: 16/689,786 - Filed: 2019-11-20 - Published: 2020-09-10 - Granted: 2021-09-14 - Earliest claimed: 2019-03-05 - Assignees: Astee International Limited - Applicants: Astec International Limited - Inventors: James Sigamani - Web page: https://patentgrep.com/patent/US11121633B2 ## CPC - H01F 30/10: Single-phase transformers (H01F30/16 takes precedence) - H01F 27/2804: {Printed windings} - H02M 1/08: Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters - H02M 3/01: {Resonant DC/DC converters} - H02M 3/33571: {Half-bridge at primary side of an isolation transformer} - H01F 27/24: Magnetic cores - H01F 27/324: {Insulation between coil and core, between different winding sections, around the coil; Other insulation structures} - H02M 1/0058: {by employing soft switching techniques, i.e. commutation of transistors when applied voltage is zero or when current flow is zero (using an auxiliary actively switched resonant commutation circuit connected to an intermediate DC voltage or between two push-pull branches of an inverter bridge H02M7/4811; in resonant inverters H02M7/4815; in inverters operating from a resonant DC source H02M7/4826)} - H02M 1/0074: {Plural converter units whose inputs are connected in series} - H02M 3/285: {Single converters with a plurality of output stages connected in parallel (parallel operation of a plurality of converters in DC distribution networks H02J1/10)} - Y02B 70/10: Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES - 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) - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract A switch-mode DC-DC power converter includes one or more input terminals and output terminals, and a transformer coupled between the input and output terminals. The transformer includes a plurality of winding sets. Each winding set includes a primary winding and a secondary winding magnetically coupled with one another. The primary winding and the secondary winding include the same number of turns. The primary windings of the plurality of winding sets are connected in series and the secondary windings of the plurality of winding sets are connected in parallel. The power converter also includes at least one spacer positioned to separate an adjacent pair of the plurality of winding sets. A magnetic coupling between the adjacent pair of the plurality of winding sets is less than the magnetic coupling between the primary winding and the secondary winding within each winding set. ## Claims ### Claim 1 An interleaved LLC power converter, comprising: one or more input terminals for receiving an input voltage from a voltage source; one or more output terminals for supplying an output voltage to a load; a first LLC converter including a first transformer and a first spacer, the first transformer coupled between the input and output terminals, the first transformer including a first plurality of winding sets each including a primary winding and a secondary winding magnetically coupled with one another, the first spacer positioned to separate an adjacent pair of the first plurality of winding sets, the primary windings of the first plurality of winding sets connected in series and the secondary windings of the first plurality of winding sets connected in parallel; and a second LLC converter interleaved with the first LLC converter, the second LLC converter including a second transformer and a second spacer, the second transformer coupled between the input and output terminals, the second transformer including a second plurality of winding sets each including a primary winding and a secondary winding magnetically coupled with one another, the second spacer positioned to separate an adjacent pair of the second plurality of winding sets, the primary windings of the second plurality of winding sets connected in series and the secondary windings of the second plurality of winding sets connected in parallel. ### Claim 2 (depends on 1) The power converter of claim 1, wherein each LLC converter includes at least two switches, a capacitor and an inductor, and the switches, capacitor and inductor are coupled between the one or more input terminals and the transformer of said LLC converter. ### Claim 3 (depends on 2) The power converter of claim 2, further comprising a controller for controlling switching operation of the switches of the first and second LLC converters to operate the first and second LLC converters with one of a forty-five degree phase shift, a sixty degree phase shift, and a ninety degree phase shift, relative to one another. ### Claim 4 (depends on 1) The power converter of claim 1, wherein the first and second pluralities of winding sets each comprise exactly two winding sets, and a turns ratio of each LLC converter is two to one. ### Claim 5 (depends on 1) The power converter of claim 1, wherein the first and second pluralities of winding sets each comprise exactly four winding sets, and a turns ratio of each LLC converter is four to one. ### Claim 6 (depends on 1) The power converter of claim 1, wherein each winding comprises a planar winding including one turn per layer.