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 .
Response to Arguments
Applicant's arguments filed 23 January 2026 have been fully considered but they are not persuasive. The Applicant provides two main arguments: that Yoscovich (US 2014/0292085) discloses a “keep alive” signal to micro-inverters and therefore does not disclose a “keep alive” signal to a DC/DC conversion circuit and that a second preset current would not be obvious to include.
Regarding the first argument, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). The primary reference, US 2022/0360214 by Kratochvil et al., discloses controlling the operation of DC/DC conversion circuitry as presented below. Yoscovich merely discloses an alternate way to control the operational state of conversion circuitry.
Regarding the second argument, Kratochvil does disclose the use of a second preset current (see below and paragraph 0027). The use of this second preset current in claim 3 is irrelevant for the limitations of claim 2. As claim 2 is written, the second preset current only acts a first step in reaching the first preset current. That is, it is only a second threshold that allows a first threshold to perform a function. This is further explained below.
Given the above, the rejection is maintained.
Claim Objections
Claims 5 and 14 are objected to because of the following informalities: the newly added limitation “from the absolute value of the at least one direct-current power” is believed to read “the at least one direct-current power supply”. 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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
5. Claims 1-2, 6-11 and 15-18 are rejected under 35 U.S.C. 103 as being unpatentable over US 2022/0360214 by Kratochvil et al. (Kratochvil hereinafter) in view of US 2014/0292085 by Yoscovich et al. (Yoscovich hereinafter).
Regarding claim 1, Kratochvil discloses a method for processing arc fault [see at least Abstract], applied to an inverter [see at least Figure 5, (40)], wherein the inverter comprises an inversion circuit [see at least Figure 5, (41)] and at least one DC/DC conversion circuit [see at least Figure 5, (21)] connected to a direct-current side of the inverter [see at least Figure 5, (41) to (21)], wherein the method comprises: in response to detecting a suspected arc, stopping a first DC/DC conversion circuit [see at least Figure 5, (21)] where the suspected arc occurs [see at least paragraph 0012, “during an inactive time window, the power flow P between the DC source and the output of the circuit arrangement is interrupted”], and maintaining remaining DC/DC conversion circuits operating normally [see at least paragraph 0074, “if an arc 9, in particular a series arc, is now determined within one of the PV strings 45 by means of the control circuit 5, only that switching circuit 10, that is to say that DC-DC converter 21, which is assigned to that PV string 45…is set to the second operating mode BM2…”]; waiting for a first preset period [see at least Figure 4, (∆t2)], and determining whether a current at a power supply side [see at least Figure 5, (7)] of the first DC/DC conversion circuit is less than a first preset current [see at least Figure 4, (31) or (32), (I1); paragraph 0070]; and determining that an arc fault occurs, in response to the current at the power supply side being less than the first preset current [see at least Figure 4, (35); paragraph 0070; paragraph 0011, “in the inactive time window falls below the current threshold value”].
Kratochvil fails to disclose stopping outputting a control signal to a first DC/DC conversion circuit where the suspected arc occurs. However, Yoscovich discloses DC power sources [see at least Figure 4b, (100)] connected to serial connected converters [see at least Figure 4b, (402)] that use a keep-alive signal for controlling whether a converter remains operational [see at least paragraph 0040] or is bypassed because of a fault [see at least paragraph 0012, “The output terminals preferably have a current bypass in the event of a failure…”].
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the Applicant's invention to modify the arc fault detection system of Kratochvil to utilize a keep-alive signal, as disclosed by Yoscovich, as an alternative for disconnecting a faulty converter with continuous central control. Thus, providing rapid response to faults, maintaining safety to components and preventing possible fires due to arcing.
Regarding claim 2, Kratochvil in view of Yoscovich teaches the method according to claim 1.
Kratochvil discloses wherein after waiting for the first preset period and before the determining whether the current at the power supply side of the first DC/DC conversion circuit is less than the first preset current [see at least paragraph 0011, “and signaling of an arc presence criterion if the input current Iin detected in the inactive time window falls below the current threshold value ITH”].
Kratochvil discloses the use of a further current threshold for comparison to the input current [see at least paragraph 0027, “in that the detected input current Iin falls below a further current threshold value ITH2…”], but Kratochvil in view of Yoscovich fails to explicitly teach the method further comprises: determining whether each current of at least one direct-current power supply connected to the power supply side of the first DC/DC conversion circuit is greater than a second preset current respectively; and in response to any current of the at least one direct-current power supply connected to the power supply side of the first DC/DC conversion circuit being less than or equal to the second preset current, determining whether the current at the power supply side of the first DC/DC conversion circuit is less than the first preset current. However, this is merely using a second threshold, similar to the first threshold, which provides a buffer for the first threshold. As written in the claim, the second preset current is higher than the first preset current and once the power supply side current falls below or is equal to the second present current, it can then be determined if the power supply side current is below the first preset current. No other functionality is given to the second preset current detection.
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the Applicant's invention to modify the arc fault detection system of Kratochvil in view of Yoscovich to include a second preset current, as discussed in Kratochvil, to create a buffer for detecting arcing to further limit the amount of false detection of arcing. Thus, ensuring a more stable system without false arc detection.
Regarding claim 6, Kratochvil in view of Yoscovich teaches the method according to claim 1.
Kratochvil discloses wherein after determining whether the current at the power supply side of the first DC/DC conversion circuit is less than the first preset current, the method further comprises: determining, in response to the current at the power supply side being greater than or equal to the first preset current, that no arc fault occurs [see at least Figure 4; paragraph 0070].
Regarding claim 7, Kratochvil in view of Yoscovich teaches the method according to claim 1.
Kratochvil discloses further comprising: recording, in response to detecting the suspected arc, a voltage value and a current value of the first DC/DC conversion circuit where the suspected arc occurs [see at least Figure 4; paragraph 0070].
Regarding claim 8, Kratochvil in view of Yoscovich teaches the method according to claim 1.
Kratochvil discloses further comprising: on determining that the arc fault occurs, generating and outputting alarm information [see at least Abstract, “an arc presence criterion is signaled”; paragraph 0014].
Regarding claim 9, Kratochvil discloses an inverter [see at least Figure 5, (40)], comprising a controller [see at least Figure 5, (5)], an inversion circuit [see at least Figure 5, (41)] and at least one DC/DC conversion circuit [see at least Figure 5, (21)], wherein a power supply side of the at least one DC/DC conversion circuit, serving as an interface corresponding to a direct-current side of the inverter [see at least Figure 5, (7)], is configured to be connected to at least one direct-current power supply [see at least Figure 5, (45)]; a bus side of the DC/DC conversion circuit is connected to a direct-current side of the inversion circuit through a direct-current bus [see at least Figure 5, (21) to (41)]; an alternating-current side of the inversion circuit, serving as an alternating-current side of the inverter [see at least Figure 5, (44) to (46)]; the controller is configured to control the inversion circuit and the DC/DC conversion circuit [see at least Figure 5, (5)]; wherein the controller is further configured to: in response to detecting a suspected arc, stop a first DC/DC conversion circuit where the suspected arc occurs, and maintain remaining DC/DC conversion circuits operating normally [see at least paragraph 0074]; wait for a first preset period, and determine whether a current at a power supply side of the first DC/DC conversion circuit is less than a first preset current [see at least Figure 4, (31) or (32), (I1); paragraph 0070]; and determine that an arc fault occurs, in response to the current at the power supply side is less than the first preset current [see at least Figure 4, (35); paragraph 0070].
Kratochvil fails to disclose stopping outputting a control signal to a first DC/DC conversion circuit where the suspected arc occurs. However, Yoscovich discloses DC power sources [see at least Figure 4b, (100)] connected to serial connected converters [see at least Figure 4b, (402)] that use a keep-alive signal for controlling whether a converter remains operational [see at least paragraph 0040] or is bypassed because of a fault [see at least paragraph 0012, “The output terminals preferably have a current bypass in the event of a failure…”].
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the Applicant's invention to modify the arc fault detection system of Kratochvil to utilize a keep-alive signal, as disclosed by Yoscovich, as an alternative for disconnecting a faulty converter with continuous central control. Thus, providing rapid response to faults, maintaining safety to components and preventing possible fires due to arcing.
Regarding claim 10, Kratochvil in view of Yoscovich teaches the inverter according to claim 9.
Kratochvil discloses wherein the at least one direct-current power supply comprises a photovoltaic string or a battery cluster [see at least Figure 5, (45)].
Regarding claim 11, Kratochvil in view of Yoscovich teaches the inverter according to claim 9.
Kratochvil discloses the use of a further current threshold for comparison to the input current [see at least paragraph 0027, “in that the detected input current Iin falls below a further current threshold value ITH2…”], but Kratochvil in view of Yoscovich fails to explicitly teach wherein the controller is further configured to: determine whether each current of the at least one direct-current power supply connected to the power supply side of the first DC/DC conversion circuit is greater than a second preset current respectively; and in response to any current of the at least one direct-current power supply connected to the power supply side of the first DC/DC conversion circuit being less than or equal to the second preset current, determining whether the current at the power supply side of the first DC/DC conversion circuit is less than the first preset current. However, this is merely using a second threshold, similar to the first threshold, which provides a buffer for the first threshold. As written in the claim, the second preset current is higher than the first preset current and once the power supply side current falls below or is equal to the second present current, it can then be determined if the power supply side current is below the first preset current. No other functionality is given to the second preset current detection.
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the Applicant's invention to modify the arc fault detection system of Kratochvil in view of Yoscovich to include a second preset current, as discussed in Kratochvil, to create a buffer for detecting arcing to further limit the amount of false detection of arcing. Thus, ensuring a more stable system without false arc detection.
Regarding claim 15, Kratochvil in view of Yoscovich teaches the inverter according to claim 9.
Kratochvil discloses wherein the controller is further configured to: determine, in response to the current at the power supply side being greater than or equal to the first preset current, that no arc fault occurs [see at least Figure 4; paragraph 0070].
Regarding claim 16, Kratochvil in view of Yoscovich teaches the inverter according to claim 9.
Kratochvil discloses wherein the controller is further configured to: record, in response to detecting the suspected arc, a voltage value and a current value of the first DC/DC conversion circuit where the suspected arc occurs [see at least Figure 4; paragraph 0070].
Regarding claim 17, Kratochvil in view of Yoscovich teaches the inverter according to claim 9.
Kratochvil discloses wherein the controller is further configured to: generate and output alarm information, on determining that the arc fault occurs [see at least Abstract, “an arc presence criterion is signaled”; paragraph 0014].
Regarding claim 18, Kratochvil discloses a photovoltaic system, comprising at least one photovoltaic string [see at least Figure 5, (45)] and an inverter [see at least Figure 5, (40)], wherein the inverter comprises: a controller [see at least Figure 5, (5)], an inversion circuit [see at least Figure 5, (41)] and at least one DC/DC conversion circuit [see at least Figure 5, (21)], wherein a power supply side of the at least one DC/DC conversion circuit, serving as an interface corresponding to a direct-current side of the inverter, is configured to be connected to at least one direct-current power supply [see at least Figure 5, (7) to (45)]; a bus side of the DC/DC conversion circuit is connected to a direct-current side of the inversion circuit through a direct-current bus; an alternating-current side of the inversion circuit, serving as an alternating-current side of the inverter [see at least Figure 5, (44) to (46)]; the controller is configured to control the inversion circuit and the DC/DC conversion circuit [see at least Figure 5, (5)]; wherein the controller is further configured to: in response to detecting a suspected arc, stop a first DC/DC conversion circuit where the suspected arc occurs, and maintain remaining DC/DC conversion circuits operating normally [see at least paragraph 0074]; wait for a first preset period, and determine whether a current at a power supply side of the first DC/DC conversion circuit is less than a first preset current [see at least Figure 4, (31) or (32), (I1); paragraph 0070]; and determine that an arc fault occurs, in response to the current at the power supply side is less than the first preset current [see at least Figure 4, (35); paragraph 0070]; and the interface corresponding to the direct-current side of the inverter is connected to the at least one photovoltaic string [see at least Figure 5, (45)].
Kratochvil fails to disclose stopping outputting a control signal to a first DC/DC conversion circuit where the suspected arc occurs. However, Yoscovich discloses DC power sources [see at least Figure 4b, (100)] connected to serial connected converters [see at least Figure 4b, (402)] that use a keep-alive signal for controlling whether a converter remains operational [see at least paragraph 0040] or is bypassed because of a fault [see at least paragraph 0012, “The output terminals preferably have a current bypass in the event of a failure…”].
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the Applicant's invention to modify the arc fault detection system of Kratochvil to utilize a keep-alive signal, as disclosed by Yoscovich, as an alternative for disconnecting a faulty converter with continuous central control. Thus, providing rapid response to faults, maintaining safety to components and preventing possible fires due to arcing.
6. Claims 5 and 14 are rejected under 35 U.S.C. 103 as being unpatentable over US 2022/0360214 by Kratochvil et al. (Kratochvil hereinafter) in view of US 2014/0292085 by Yoscovich et al. (Yoscovich hereinafter) in further view of US 2017/0324236 by Tomita et al. (Tomita hereinafter).
Regarding claim 5, Kratochvil in view of Yoscovich teaches the method according to claim 2.
Kratochvil in view of Yoscovich fails to teach wherein the determining whether each current of the at least one direct-current power supply connected to the power supply side of the first DC/DC conversion circuit is greater than the second preset current respectively comprises: calculating an absolute value of each current of the at least one direct-current power supply connected to the power supply side of the first DC/DC conversion circuit; and determining whether a minimum value from the absolute value of the at least one direct-current power is greater than the second preset current. However, Tomita discloses this limitation [see at least paragraphs 0060, 0076 and 0094].
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the Applicant's invention to utilize absolute value in the system to normalize variations in current enabling detecting of variations either high or low. Thus, stabilizing the system from variations.
Regarding claim 14, Kratochvil in view of Yoscovich teaches the inverter according to claim 11.
Kratochvil in view of Yoscovich fails to teach wherein the controller is further configured to: calculate an absolute value of each current of the at least one direct-current power supply connected to the power supply side of the first DC/DC conversion circuit; and determine whether a minimum value from the absolute value of the at least one direct-current power is greater than the second preset current. However, Tomita discloses this limitation [see at least paragraphs 0060, 0076 and 0094].
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the Applicant's invention to utilize absolute value in the system to normalize variations in current enabling detecting of variations either high or low. Thus, stabilizing the system from variations.
Allowable Subject Matter
7. Claims 3-4 and 12-13 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.
8. The following is a statement of reasons for the indication of allowable subject matter: the prior art, alone or in combination, fails to disclose controlling a voltage at the power supply side of the first DC/DC conversion circuit to be less than a safety voltage, in a case that each current of the at least one direct-current power supply connected to the power supply side of the first DC/DC conversion circuit is greater than the second preset current; and waiting for a second preset period, and adjusting the voltage at the power supply side of the first DC/DC conversion circuit to be a voltage value before stopping outputting the control signal; and determining whether the current at the power supply side of the first DC/DC conversion circuit is less than the first preset current.
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/JOEL BARNETT/Examiner, Art Unit 2836
/REGIS J BETSCH/SPE, Art Unit 2836
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