# US 6,721,191 B2 · Resonant converter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,721,191 B2 - Document ID: US6721191B2 - Status: Granted - Kind: B2 - Application number: 10/140,667 - Filed: 2002-05-08 - Published: 2002-12-05 - Granted: 2004-04-13 - Earliest claimed: 2001-05-09 - Assignees: Koninklijke Philips Electronics N.V. - Inventors: Thomas Duerbaum; Reinhold Elferich - Web page: https://patentgrep.com/patent/US6721191B2 ## CPC - H02M 3/33561: {having more than one ouput with independent control} - 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 - 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 The invention relates to a resonant converter (1) which has multiple outputs (7a, 7b) and contains a transformer (4) with a primary winding (5) and at least two secondary windings (6a, 6b) having different winding directions. In this way it is possible to design as cost-effectively as possible a resonant converter with multiple outputs, two of which can be controlled separately from each other. ## Claims ### Claim 1 A resonant converter comprising: multiple converter outputs; a transformer including a primary winding and at least two secondary windings of different winding directions, each secondary winding being electrically connected to one of said multiple converter outputs; at least two switching elements for chopping an input d-c voltage to yield a chopped input d-c voltage; and a feedback loop including a regulating circuit for regulating a frequency and a duty cycle of the chopped input d-c voltage. ### Claim 2 (depends on 1) The resonant converter of claim 1, wherein said at least two secondary windings includes a first group of secondary windings with one or more secondary windings having a first winding direction, and a second group of secondary windings with one or more secondary windings having a second winding direction; and wherein at least two of said at least two secondary windings are electrically separated from one another. ### Claim 3 (depends on 1) The resonant converter of claim 1, wherein said at least two secondary windings includes a first group of secondary windings with one or more secondary windings having a first winding direction, and a second group of secondary windings with one or more secondary windings having a second winding direction; and wherein at least two of said at least two secondary windings are electrically connected to one another. ### Claim 4 (depends on 3) The resonant converter of claim 3, wherein said at least two secondary windings are connected to a ground potential. ### Claim 5 (depends on 1) The resonant converter of claim 1, wherein a resonant frequency of the resonant converter is determined by a main inductance and a plurality of leakage inductances of said transformer and by a capacitive element. ### Claim 6 (depends on 1) The resonant converter of claim 1, further comprising at least one additional inductive element, wherein, in addition to said transformer, said at least one additional inductive element co-determines a resonant frequency of the resonant converter. ### Claim 7 (depends on 1) The resonant converter of claim 1, wherein each secondary windings of said transformer is electrically connected to one of said multiple converter outputs by way of one diode and one output filter. ### Claim 8 (depends on 1) The resonant converter of claim 1, wherein different ratios of output voltage to number of turns are provided in respect of associated secondary windings having different winding directions. ### Claim 9 (depends on 2) The resonant converter of claim 2, further comprising means for deriving a measuring signal for regulating converter output voltages from each multiple output associated with said first group of secondary windings. ### Claim 10 (depends on 3) The resonant converter of claim 3, further comprising means for deriving a measuring signal for regulating converter output voltages from each multiple output associated with said first group of secondary windings. ### Claim 11 A resonant convert comprising: an inverter operable to convert a d-c voltage into an a-c voltage; a transformer including a first secondary winding electrically connected to said inverter to generate a first secondary voltage as a function of the a-c voltage, and a second secondary winding electrically connected to said inverter to generate a second secondary voltage as a function of the a-c voltage, wherein said first secondary winding and said second secondary winding have different winding directions; and a regulation circuit electrically connected to said first secondary winding and said second secondary winding to regulate a frequency and a duty cycle of the a-c voltage as a function of the first secondary voltage and the second secondary voltage. ### Claim 12 (depends on 11) The resonant converter of claim 11, wherein said first secondary winding and said second secondary winding are electrically separated from one another. ### Claim 13 (depends on 11) The resonant converter of claim 11, wherein said first secondary winding and said second secondary winding are electrically connected to each another. ### Claim 14 (depends on 11) The resonant converter of claim 11, wherein said first secondary winding and said second secondary winding are electrically connected to a ground potential. ### Claim 15 (depends on 11) The resonant converter of claim 11, further comprising means for establishing a resonant frequency of the resonant converter. ### Claim 16 (depends on 11) The resonant converter of claim 11, further comprising a rectifying and filtering circuit electrically connected to said first secondary winding to rectify and filter the first secondary voltage, wherein said rectifying and filtering circuit exclusively consists of a diode and a filter. ### Claim 17 (depends on 11) The resonant converter (1) of claim 11, further comprising means for rectifying and filtering the first secondary voltage. ### Claim 18 (depends on 11) The resonant converter of claim 11, wherein said a regulation circuit includes means for comparing the first secondary voltage to a first reference voltage and for comparing the second secondary voltage to a second reference voltage. ### Claim 19 A resonant converter, comprising: an inverter operable to convert a d-c voltage into an a-c voltage; a transformer including a first secondary winding electrically connected to said inverter to generate a first secondary voltage as a function of the a-c voltage, and a second secondary winding electrically connected to said inverter to generate a second secondary voltage as a function of the a-c voltage, wherein said first secondary winding and said second secondary winding have different winding directions; and means for regulating a frequency and a duty cycle of the a-c voltage as a function of the first secondary voltage and the second secondary voltage.