DETAILED ACTION
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 .
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 12/19/24 and 10/9/25 have been considered by the examiner.
Specification
The title of the invention is not descriptive. A new title is required that is clearly indicative of the invention to which the claims are directed.
A title such as the following is suggested: Power Converter with Auxiliary Resonant Switching Circuit.
Claim Objections
Claims 1-9 are objected to because of the following informalities:
Claim 1, line 40, recites “a high-level period”, which has already been recited for several signals and should be claimed to differentiate the claimed signal, such as by claiming ‘the high-level period of the control signal for the bidirectional switch’.
Similarly for claim 9.
Appropriate correction is required.
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.
Claim(s) 1-2 are rejected under 35 U.S.C. 103 as being unpatentable over Hiruma (JP H11332250A) in view of Zhang (CN 204696954U) and further in view of Amini (US 2025/0096700).
With respect to claim 1, Hiruma discloses a power converter comprising: a first DC terminal (Fig. 1 P) and a second DC terminal (Fig. 1 N); a power converter circuit including a plurality of first switching elements (Fig. 1 Tu+,Tv+,Tw+) and a plurality of second switching elements (Fig. 1 Tu-,Tv-,Tw-), the power converter circuit being implemented as a parallel connection of a plurality of switching circuits (Fig. 1 three half bridges) in each of which one of the plurality of first switching elements and a corresponding one of the plurality of second switching elements are connected one to one in series, the plurality of first switching elements being connected to the first DC terminal, the plurality of second switching elements being connected to the second DC terminal; a plurality of AC terminals (Fig. 1 U,V,W) provided one to one for the plurality of switching circuits, respectively, each of the plurality of AC terminals being connected to a connection node between the first switching element and the second switching element of a corresponding one of the plurality of switching circuits; a plurality of bidirectional switches (Fig. 3 13a,13b,23a,23b,33a,33b) provided one to one for the plurality of switching circuits, each of the plurality of bidirectional switches having a first terminal thereof connected to the connection node (Fig. 1 half bridge output node) between the first switching element and the second switching element of a corresponding one of the plurality of switching circuits; a plurality of resonant capacitors (Fig. 1 11,21,31) provided one to one for the plurality of bidirectional switches, respectively, each of the plurality of resonant capacitors being connected between the first terminal of a corresponding one of the plurality of bidirectional switches and the second DC terminal; a regenerative capacitor (Fig. 1 3) having a third terminal and a fourth terminal, the third terminal of the regenerative capacitor being connected to either the first DC terminal or the second DC terminal (Fig. 3 N); a first resonant inductor (Fig. 3 14) connected between a first bidirectional switch belonging to the plurality of bidirectional switches and the fourth terminal of the regenerative capacitor; a second resonant inductor (Fig. 3 24) connected between a second bidirectional switch belonging to the plurality of bidirectional switches and the fourth terminal of the regenerative capacitor; a third resonant inductor (Fig. 3 34) connected between a third bidirectional switch belonging to the plurality of bidirectional switches and the fourth terminal of the regenerative capacitor; and a controller (Fig. 3 40) configured to apply a PWM signal to each of the plurality of first switching elements and the plurality of second switching elements, the PWM signal having a potential alternating between a high level and a low level (Fig. 1 gate turned ON and OFF). Hiruma remains silent as to the control of the switching circuits. It was well known before the effective filing date of the claimed invention to switch the bidirectional switches to overlap with the deadtime, since that is the function of the bidirectional switches to facilitate the zero voltage switching.
Zhang discloses the controller being configured to: perform a first control operation including: setting, with respect to each of the plurality of switching circuits (Fig. 1 half bridges S1-S2,S3-S4,S5-S6), a dead time (Fig. 3 t2-t4) between a high-level period (Fig. 3 S1 up to t2) of the PWM signal for the first switching element (Fig. 1 S1,S3,S5) and a high-level period of the PWM signal (Fig. 3 S2 after t3) for the second switching element (Fig. 1 S2,S4,S6); causing a high-level period of a control signal for each of the plurality of bidirectional switches (Fig.1 Sr1-Sr6), corresponding to one of the plurality of switching circuits, to overlap (Fig. 3 Sr1 active from t0-t5) with the dead time; and setting a beginning of the high-level period at a point in time earlier (Fig. 3 t0 before t2) than a beginning of the dead time by an additional time (Fig. 3 t0 to t2). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to implement the controller being configured to: perform a first control operation including: setting, with respect to each of the plurality of switching circuits, a dead time between a high-level period of the PWM signal for the first switching element and a high-level period of the PWM signal for the second switching element; causing a high-level period of a control signal for each of the plurality of bidirectional switches, corresponding to one of the plurality of switching circuits, to overlap with the dead time; and setting a beginning of the high-level period at a point in time earlier than a beginning of the dead time by an additional time, in order to improve the efficiency of the power converter by implementing the switching to generate the zero voltage switching.
Hiruma also remains silent as to maintaining the regenerative capacitor voltage which was a known issue before the effective filing date of the claimed invention.
Amini discloses a power converter controller configured to acquire a potential (Fig. 1 180) detected at the fourth terminal (Fig. 1 140) of the regenerative capacitor (Fig. 1 124); perform, when the potential (Fig. 2 VDC2) detected is less (Fig. 2 ΔVDC < 0) than a first threshold value (Fig. 3 310 deadzone threshold from 0) that is less than one half of a value of voltage applied between the first DC terminal (Fig. 1 +) and the second DC terminal (Fig. 1 -), a second control operation including raising a potential (Fig. 2 260 adjust switching to increase VDC2) at the fourth terminal of the regenerative capacitor; and perform, when the potential detected is greater (Fig. 2 ΔVDC > 0) than a second threshold value (Fig. 3 310 deadzone threshold from 0) that is greater than one half of the value of the voltage applied between the first DC terminal and the second DC terminal, a third control operation including lowering the potential (Fig. 3 2 260 adjusts switching to lower VDC2) at the fourth terminal of the regenerative capacitor. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to implement acquire a potential detected at the fourth terminal of the regenerative capacitor; perform, when the potential detected is less than a first threshold value that is less than one half of a value of voltage applied between the first DC terminal and the second DC terminal, a second control operation including raising a potential at the fourth terminal of the regenerative capacitor; and perform, when the potential detected is greater than a second threshold value that is greater than one half of the value of the voltage applied between the first DC terminal and the second DC terminal, a third control operation including lowering the potential at the fourth terminal of the regenerative capacitor, in order to maintain the regenerative capacitor voltage near the midpoint of the first and second terminal voltages, so the zero voltage switching can be achieved when activating the bidirectional switch.
With respect to claim 2, Hiruma in view of Zhang and Amini make obvious the power converter of claim 1, wherein the controller is configured to acquire the potential detected at the fourth terminal of the regenerative capacitor every cycle (Amini Fig. 2 VDC2 detected every cycle in order to generate gate signals every cycle) of a carrier signal (Fig. 2 carrier of modulation) , the second control operation is an operation of controlling, according to respective polarities (Fig. 2 230) of a plurality of output currents (in combination Fig. 2 IL for each phase) supplied from the plurality of AC terminals, the plurality of bidirectional switches to raise (Fig. 2 VDC2 raised when VDC2 < VDC1) the potential at the fourth terminal of the regenerative capacitor, and the third control operation is an operation of controlling, according to the respective polarities (Fig. 2 230) of the plurality of output currents (in combination, Fig. 2 IL for each phase) supplied from the plurality of AC terminals, the plurality of bidirectional switches to lower (Fig. 2 lower VDC2 when VDC2 > VDC1) the potential at the fourth terminal of the regenerative capacitor.
Allowable Subject Matter
Claim 9 is objected to for the reasons stated above but would be allowed if the claim objection stated above were overcome, while Claims 3-8 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims and if the claim objection stated above were overcome. The following is an examiner’s statement of reasons for indicating allowable subject matter for claim 9:
The prior art does not disclose or suggest, to perform, when the potential detected is less than a first threshold value that is less than one half of a value of voltage applied between the first DC terminal and the second DC terminal, a second control operation including applying, according to respective polarities of a plurality of output currents supplied from the plurality of AC terminals, a control signal having a high-level period, associated with a charging operation of the regenerative capacitor, to one bidirectional switch belonging to the plurality of bidirectional switches besides applying a control signal, having a high-level period overlapping with the dead time, to the one bidirectional switch in one cycle of a carrier signal; and perform, when the potential detected is greater than a second threshold value that is greater than one half of the value of the voltage applied between the first DC terminal and the second DC terminal, a third control operation of applying, according to respective polarities of a plurality of output currents supplied from the plurality of AC terminals, a control signal having a high-level period, associated with a discharging operation of the regenerative capacitor, to one bidirectional switch belonging to the plurality of bidirectional switches besides applying the control signal, having the high-level period overlapping with the dead time, to the one bidirectional switch in one cycle of the carrier signal.
The following is a statement of reasons for the indication of allowable subject matter:
With respect to claim 3, the prior art does not disclose or suggest, in combination with the limitations of the base claim and any intervening claims, primarily, wherein the controller is configured to: perform the second control operation by setting, according to the respective polarities of the plurality of output currents supplied from the plurality of AC terminals, a high-level period of one of the plurality of bidirectional switches, which participates in a discharging operation of the regenerative capacitor, at zero, and perform the third control operation by setting, according to the respective polarities of the plurality of output currents supplied from the plurality of AC terminals, a high-level period of one of the plurality of bidirectional switches, which participates in a charging operation of the regenerative capacitor, at zero.
With respect to claim 5, the prior art does not disclose or suggest, in combination with the limitations of the base claim and any intervening claims, primarily, wherein the controller is configured to: perform the second control operation by shortening, according to the respective polarities of the plurality of output currents supplied from the plurality of AC terminals, a high-level period of a control signal for a bidirectional switch, which participates in a discharging operation of the regenerative capacitor, out of the plurality of bidirectional switches to make an integrated value of a current flowing through the regenerative capacitor in one cycle of a carrier signal equal to zero; and perform the third control operation by shortening, according to the respective polarities of the plurality of output currents supplied from the plurality of AC terminals, a high-level period of a control signal for a bidirectional switch, which participates in a charging operation of the regenerative capacitor, out of the plurality of bidirectional switches to make the integrated value of the current flowing through the regenerative capacitor in one cycle of the carrier signal equal to zero.
With respect to claim 7, the prior art does not disclose or suggest, in combination with the limitations of the base claim and any intervening claims, primarily, wherein the controller is configured to: perform the second control operation by extending, according to the respective polarities of the plurality of output currents supplied from the plurality of AC terminals, the shortest one of high-level periods of a control signal for a bidirectional switch, which participates in a charging operation of the regenerative capacitor, out of the plurality of bidirectional switches to make an integrated value of a current flowing through the regenerative capacitor in one cycle of a carrier signal equal to zero; and perform the third control operation by extending, according to the respective polarities of the plurality of output currents supplied from the plurality of AC terminals, the shortest one of high-level periods of a control signal for a bidirectional switch, which participates in a discharging operation of the regenerative capacitor, out of the plurality of bidirectional switches to make the integrated value of the current flowing through the regenerative capacitor in one cycle of the carrier signal equal to zero.
The aforementioned limitations in combination with all remaining limitations of the respective claims are believed to render the aforementioned indicated claim and any dependent claims thereof patentable over the art of record.
Any comments considered necessary by applicant must be submitted no later than the payment of the issue fee and, to avoid processing delays, should preferably accompany the issue fee. Such submissions should be clearly labeled “Comments on Statement of Reasons for Allowance.”
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Lai (US 5,642,273) and Lai (US 5,710,698) disclose resonant snubber circuits in an inverter. Moriarty (US 4,336,585) discloses detecting a voltage of the regenerative capacitor. Inoshita (US 6,069,809) and Takizawa (JP2011078204A) discloses a resonant inverter.
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/HARRY R BEHM/Primary Examiner, Art Unit 2838
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