DETAILED ACTION
This Office action is in response to the application filed on 04 December 2024.
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1-8, 10-17, and 19-20 are rejected under 35 U.S.C. 103 as being unpatentable over Yuyang Jiang et. al (IECON 2022 – 48th Annual Conference of the IEEE Industrial Electronics Society; hereafter “Jiang”) in view of Jong-Woo Kim et. al (IEEE Transactions on Power Electronics, Volume: 29, Issue: 8, August 2014; hereafter “Kim”).
-Regarding claim 1:
Jiang discloses:
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A power converter system, comprising: an input and an output (Fig. 3; Vin and Vo); a power converter between the input and the output, the power converter comprising: a transformer comprising N elemental transformers (Fig. 3; red circles); primary-side switches (Fig. 3; Q1, Q2) coupled to a primary side of the transformer and operating based on a primary-side switching operation; and secondary-side switches(Fig. 3; SR1-SR8) coupled to each elemental transformer among the N elemental transformers at a secondary side of the transformer; and a controller (Fig. 5 and paragraph IV; “ The digital controller adopts a DSP……”) configured to generate switching control signals for the secondary-side switches (Fig. 3; SR1-SR8) such that
However, Jiang does not disclose two operating modes in DC to DC LLC power converter with a matrix transformer.
Kim, in the same field of endeavor, discloses:
a switching operation in at least one elemental transformer among the N elemental transformers is phase-shifted with respect to the primary-side switching operation (abstract; “ the SR switches are controlled using phase-shifted switching signals in order that”, where the SR switches means the secondary-side switches.), wherein a switching operation in at least one other elemental transformer among the N elemental transformers is in-phase with respect to the primary-side switching operation (paragraph II; “the SR switches are controlled with in-phase gate signals with the gate signals for primary switches.”, where the SR switches means the secondary-side switches.)
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device described in Jiang such that a commonly used phase-shifted control of the secondary side switches described in Kim is applied to a DCX_LLC resonant converter. Doing so allows for obtaining very wide gain ranges for the LLC resonant converter.
-Regarding claim 13:
Jiang discloses:
A power converter system, comprising: a power converter comprising: a transformer comprising N elemental transformers (Fig. 3; red circles); primary-side switches (Fig. 3; Q1, Q2) coupled to a primary side of the transformer and operating based on a primary-side switching operation; and secondary-side switches (Fig. 3; SR1- SR8) coupled to each elemental transformer among the N elemental transformers at a secondary side of the transformer; and a controller (Fig. 5 and paragraph IV; “ The digital controller adopts a DSP……”) configured to generate switching control signals for the secondary-side switches (Fig. 3; SR1- SR8) such that: a
However, Jiang does not disclose two operating modes in DC to DC LLC power converter with a matrix transformer.
Kim, in the same field of endeavor, discloses:
a switching operation in at least one elemental transformer among the N elemental transformers is phase-shifted with respect to the primary-side switching operation (abstract; “ the SR switches are controlled using phase-shifted switching signals in order that”, where the SR switches means the secondary-side switches.), wherein a switching operation in at least one other elemental transformer among the N elemental transformers is in-phase with respect to the primary-side switching operation (paragraph II; “the SR switches are controlled with in-phase gate signals with the gate signals for primary switches.”, where the SR switches means the secondary-side switches.); and a switching operation in the at least one other elemental transformer is phase-shifted with respect to the primary-side switching operation (abstract; “ the SR switches are controlled using phase-shifted switching signals in order that”, where the SR switches means the secondary-side switches.), wherein a switching operation in the at least one elemental transformer is in-phase with respect to the primary-side switching operation (paragraph II; “the SR switches are controlled with in-phase gate signals with the gate signals for primary switches.”, where the SR switches means the secondary-side switches.).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device described in Jiang such that a commonly used phase-shifted control of the secondary side switches described in Kim is applied to a DCX_LLC resonant converter. Doing so allows for obtaining very wide gain ranges for the LLC resonant converter.
-Regarding claim 2:
Kim discloses:
The power converter system of claim 1, wherein for the switching operation in the at least one elemental transformer, the controller is further configured to: phase shift a switching operation of a half-bridge of the at least one elemental transformer with respect to the primary-side switching operation (Fig. 5; a gate control signal in one of SR switches is phase-shifted with primary switches).
-Regarding claim 3:
Kim discloses:
The power converter system of claim 2, wherein for the switching operation in the at least one elemental transformer, the controller is further configured to: cause a switching operation of the other half-bridge to be in-phase with respect to the primary-side switching operation (Fig. 4; a gate control signal in one of SR switches is in phase with primary switches).
-Regarding claim 4:
Jiang discloses:
The power converter system of claim 1, wherein for the switching operation of the at least one elemental transformer, the output is selectively connected to the power converter via the at least one different elemental transformer and shorted via the at least one elemental transformer (Fig. 2; iDR1 and iDR2 , Fig. 6; iLr and VSR).
-Regarding claim 5:
Kim discloses:
The power converter system of claim 1, wherein to generate the switching control signals for the secondary-side switches, the controller is further configured to phase shift in the at least one elemental transformer, with respect to the primary-side switching operation, using a phase-shift angle that ranges from greater than 0° to less than or equal to 180° (paragraph V; “In the nominal state,
the proposed converter operates near the resonant frequency and the phase shift angle is zero. After the ac loss at t1, Vlink and fs decrease and the phase shift angle is still zero. After fs reaches its minimum value at t2, Vout slightly decreases to (1 + R1 /(R2 + a))2.5 and the phase shift angle begins to increase to
obtain a higher conversion ratio during the hold-up time.”).
-Regarding claim 6:
Kim discloses:
The power converter system of claim 1, wherein the controller being configured to generate the switching control signals for each secondary-side switches causes a reduced frequency range operation for the power converter while providing a higher gain for the output (paragraph I; “an LLC series resonant converter regulates the output voltage by decreasing the switching frequency because its voltage conversion ratio increases as the switching frequency decreases,”, where the voltage conversion ratio means the gain for the output.).
-Regarding claim 7:
Jiang discloses:
The power converter system of claim 1, wherein: the power converter is a resonant LLC converter; and the transformer is a matrix transformer (Fig. 3; DCX-LLC resonant converter).
-Regarding claim 8:
Jiang discloses:
The power converter system of claim 7, wherein the resonant LLC converter comprises a resonant tank, the resonant tank comprising: a series resonant inductor (Lr) (Fig. 3; Lr); and a resonant capacitor (Cr) (Fig. 3; Cr), wherein a voltage across the resonant tank corresponding to the switching operation in the at least one elemental transformer is reduced as compared to an operation where the output is shorted from the power converter (Fig. 6; voltage across resonant tank-vCr decreases if load is decreased-compare the cases with 10%, 50%, and 100%).
-Regarding claim 10:
Jiang discloses:
The power converter system of claim 1, wherein the secondary-side switches coupled to each elemental transformer form a center-tap rectifier (Fig. 3; see the secondary -side).
-Regarding claim 11:
Jiang discloses:
The power converter system of claim 10, wherein: the at least one elemental transformer comprises a first plurality of elemental transformers among the N elemental transformers (Fig. 3; red circles); and the at least one other elemental transformer comprises a second plurality of elemental transformers among the N elemental transformers (Fig. 3; red circles), the second plurality being different from the first plurality.
-Regarding claim 12:
Jiang discloses:
The power converter system of claim 1, wherein the secondary-side switches coupled to each elemental transformer are connected in series to the output (Fig. 3; see the connection of SRs to output).
-Regarding claim 14:
Kim discloses:
The power converter system of claim 13, wherein: for the switching operation in the at least one elemental transformer, the controller is further configured to phase shift a switching operation of a half-bridge of the at least one elemental transformer with respect to the primary-side switching operation (Fig. 5; a gate control signal in one of SR switches is phase-shifted with primary switches); and for the switching operation in the at least one other elemental transformer, the controller is further configured to phase shift a switching operation of a half-bridge of the at least one other elemental transformer with respect to the primary-side switching operation (Fig. 5; a gate control signal in one of SR switches is phase-shifted with primary switches).
-Regarding claim 15:
Kim discloses:
The power converter system of claim 14, wherein: for the switching operation in the at least one elemental transformer, the controller is further configured to cause a switching operation of the other half-bridge of the at least one elemental transformer to be in-phase with respect to the primary-side switching operation (Fig. 4; a gate control signal in one of SR switches is in phase with primary switches); and for the switching operation in the at least one different elemental transformer, the controller is further configured to cause a switching operation of the other half-bridge of the at least one different elemental transformer to be in-phase with respect to the primary-side switching operation (Fig. 4; a gate control signal in one of SR switches is in phase with primary switches).
-Regarding claim 16:
Jiang discloses:
The power converter system of claim 13, wherein the output is shorted from the power converter during the switching operation in the at least one different elemental transformer (Fig. 2; iDR1 and iDR2 , Fig. 6; iLr and VSR).
-Regarding claim 17:
Kim discloses:
The power converter of claim 13, wherein the controller is further configured to cause the switching operation in the at least one different elemental transformer to execute after the switching operation in the at least one elemental transformer has been phase-shifted, with respect to the primary-side switching operation, using a phase-shift angle that ranges from greater than 0° to less than or equal to 180° (paragraph V; “In the nominal state, the proposed converter operates near the resonant frequency and the phase shift angle is zero. After the ac loss at t1, Vlink and fs decrease and the phase shift angle is still zero. After fs reaches its minimum value at t2, Vout slightly decreases to (1 + R1 /(R2 + a))2.5 and the phase shift angle begins to increase to obtain a higher conversion ratio during the hold-up time.”).
-Regarding claim 19:
Jiang discloses:
The power converter system of claim 13, wherein the secondary-side switches coupled to each elemental transformer form a center-tap rectifier (Fig. 3; see the secondary -side).
-Regarding claim 20:
Jiang discloses:
The power converter system of claim 19, wherein: the at least one elemental transformer comprises a first plurality of elemental transformers among the N elemental transformers (Fig. 3; red circles); and the at least one different elemental transformer comprises a second plurality of elemental transformers among the N elemental transformers (Fig. 3; red circles), the second plurality being different from the first plurality.
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Yuyang Jiang et. al (IECON 2022 – 48th Annual Conference of the IEEE Industrial Electronics Society) and Jong-Woo Kim et. al (IEEE Transactions on Power Electronics, Volume: 29, Issue: 8, August 2014) as applied to claim 1 above, and further in view of Byoung-Hee Lee et. al (INTELEC 2009 - 31st International Telecommunications Energy Conference; hereafter “Lee”).
-Regarding claim 9:
Lee discloses:
The power converter system of claim 1, wherein the secondary-side switches coupled to each elemental transformer form a full-bridge rectifier (Fig. 18 b; Full-bridge rectifier).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device described in Jiang, and Kim such that a commonly used full bridge rectifier described in Lee is applied to a DCX_LLC resonant converter. Doing so allows for obtaining very wide gain ranges for the LLC resonant converter.
Claim 18 is rejected under 35 U.S.C. 103 as being unpatentable over Yuyang Jiang et. al (IECON 2022 – 48th Annual Conference of the IEEE Industrial Electronics Society) and Jong-Woo Kim et. al (IEEE Transactions on Power Electronics, Volume: 29, Issue: 8, August 2014) as applied to claim 13 above, and further in view of Byoung-Hee Lee et. al (INTELEC 2009 - 31st International Telecommunications Energy Conference; hereafter “Lee”).
-Regarding claim 18:
Lee discloses:
The power converter system of claim 13, wherein the secondary-side switches coupled to each elemental transformer form a full-bridge rectifier (Fig. 18 b; Full-bridge rectifier).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device described in Jiang, and Kim such that a commonly used full bridge rectifier described in Lee is applied to a DCX_LLC resonant converter. Doing so allows for obtaining very wide gain ranges for the LLC resonant converter.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SEUNG HO CHOI whose telephone number is (571)272-8188. The examiner can normally be reached Monday-Thursday, 7:30 AM - 5:30 PM ET.
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/SEUNG HO CHOI/Examiner, Art Unit 2838
/CRYSTAL L HAMMOND/Supervisory Primary Examiner, Art Unit 2838
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