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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 19 June 2026 has been entered.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1-4, 6-7, 9-13, 15-16 rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention. Specific reference is made to Applicant’s corresponding PGPUB: US2025/0392226.
Re claims 1, 9 (and all claims dependent thereon), the amended claim recitation: “wherein the neutral forming converter is structured to be selectively physically coupled to one branch of the plurality of branches of the main bus” (and similar recitation in claim 9) appears to comprise New Matter not provided in or sufficiently supported by Applicant’s original disclosure. The closest disclosure appears to be in Applicant’s PGPUB: [0031-0032], [0044], Fig. 2, which generally discloses the neutral forming converter is electrically (and thus generally physically connected by electrical lines) connected to the L1,L2,N lines of the main bus, and that the neutral forming converter may be selectively activated after islanding of the system from the grid. In particular, PGPUB: [0044] generally states the neutral forming converter is either part of the load center or available to be connected to an existing load center. The disclosure does not explicitly describe the neutral forming converter as being connected via a “branch”, but the depiction of Fig. 2 could broadly be taken as the lines connecting the neutral forming converter to the main bus as a “branch”. However, the disclosure does not provide any supporting disclosure for this connection to be “selectively physically coupled”, assuming that such recitation refers to selective electrical connection similar to that provided by the breakers in the other branches. Nowhere in Applicant’s disclosure and figures does there appear to be supporting disclosure of connecting the neutral forming converter to the main bus via a branch breaker or similar feature in the manner recited by the current claim amendments. It is not apparent if some other meaning for the recitation was intended because there is no description clearly corresponding to the claim language. The claims as currently drafted therefore comprise unsupported New Matter. It is recommended that Applicant amend the claims to only recite features and use language that is fully supported by the original disclosure. Note that regardless, the feature appears to be known and taught by the prior art of record as discussed below.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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) 1-4, 6-7, 9-13, 15-16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Mu (US11545834) in view of Harrison (US2022/0360187) in view of Fornage (US9130570; incorporated by reference by Harrison), further in view of Ganger (US2022/0247175).
Re claim 1. Mu teaches a neutral forming converter (balancing converter <114> and associated control, see Mu: 3:50-65, 4:46-5:15, 6:8-15, 6:25-63, Figs. 1-4) structured for use in a load center (see Mu: 4:6-60, Figs. 1-3 regarding overall power distribution system for respective building loads, i.e. load center) having a main circuit breaker (relays <108A-B> and associated power lines <100A-C>, see Mu: 5:16-38, 6:48-50, Fig. 1) and a single-phase power source (EVSE <110>, see Mu: 4:6-45, Fig. 1 regarding providing single phase AC power across lines <L1,L2>) connected to the main circuit breaker, the main circuit breaker having a main bus (power lines <100A-C>) with a plurality of branches (respective electrical line connections to loads <112A-C> and connecting lines <110A-B> to EVSE, see Mu: 4:29-60, Fig. 1; see also further obviousness discussion below regarding structure of the main bus and branch connections) all electrically connected to a Line 1 voltage line (<100A> for L1), a Line 2 voltage line (<100B> for L2), and a neutral voltage line (<100C> for N, see Mu: 3:56-65, 4:61-5:15, Fig. 1), the neutral-forming converter comprising:
a neutral forming circuit (balancing converter <114>, see Mu: Figs. 1, 3) structured to receive as input a single-phase AC voltage across a first line conductor (converter connection to grid line <L1/106A>)and a second line conductor (converter connection to grid line <L2/106B>), the neutral forming circuit being configured to output the single-phase AC voltage with a center point neutral reference voltage, the center point neutral reference voltage being output at a neutral node (converter connection to neutral <N/106C>, see Mu: Figs. 1, 3), the center point neutral reference voltage being voltage at a midpoint between voltage of the first line conductor and voltage of the second line conductor (see Mu: 4:46-5:15, 5:39-6:24, 6:59-63, Figs. 1-3 regarding balancing converter <114> coupled to receive single phase AC across <L1,L2> when EVSE <110> supplies power and operating to provide neutral line voltage and balanced split-phase AC to loads across <L1,L2,N>; note that Figs. 2-3 are both example embodiments of the balancing converter <114> that would be coupled to receive the not split AC power from the EVSE from lines <100A,B>/<L1,L2>and output AC power with voltage balanced relative to neutral on lines <100A,B,C>/<L1,L2,N> as can be seen from Figs. 1-3 as discussed); and
a controller (see Mu: 6:8-15, 6:25-63, Figs. 1, 4 regarding controls and operations performed by the gateway system <100> and/or balancing circuit <114> including operation/activating the balancing circuit, thereby inherently requiring a corresponding control system/controller to perform the operations) configured to activate the neutral forming circuit,
wherein the neutral forming converter is structured to be physically coupled to one branch of the plurality of branches of the main bus in order to electrically connect the first line conductor to the Line 1 voltage line, the second line to the Line 2 voltage line, and the neutral node to the neutral voltage line (see Mu: 4:46-5:15, 5:39-6:24, 6:59-63, Figs. 1, 3 regarding balancing converter <114> electrically, i.e. physically, coupled via connection lines to receive single phase AC across <L1,L2> when EVSE <110> supplies power and operating to provide neutral line voltage and balanced split-phase AC to loads across <L1,L2,N>; note that Figs. 2-3 are both example embodiments of the balancing converter <114>, and also depicts how electrical line connections/branch may be provided to connect the balancing converter to the respective power lines; see also discussion of obviousness of load center structure below),
wherein the neutral forming circuit is structured such that, when a first load (load <112A>) having a first impedance is connected between the Line 1 voltage line and the neutral voltage line in any branch of the plurality of branches of the main bus and a second load (load <112B>) having a second impedance different from the first impedance is connected between the Line 2 voltage line and the neutral voltage line in any branch of the plurality of branches of the main bus, the neutral forming circuit being physically coupled to the one branch balances the voltage across the first load and the voltage across the second load (see Mu: 4:46-5:15, 5:39-6:24, Figs. 1-3 regarding design and operation of balancing converter <114> connected to the power lines <100A-C>/<L1,L2,N> to balance the voltages between L1 and L2 with respect to neutral N even when the load impedance values are different from each other). See Mu: 3:50-65, 4:46-5:15, 5:39-6:24, 6:25-63, Figs. 1-4.
Although Mu discloses an example embodiment of the neutral forming converter including general structure as an AC-AC converter that receives the single-phase AC power without neutral from EV source and produces balanced single-phase AC with neutral (see Mu: 4:46-5:15, 6:16-24, Fig. 3), Mu does not explicitly discuss the further structure of the balancing circuit. Harrison in view of Fornage, however, teaches that it is known in the art of neutral forming devices to produce balanced single phase AC voltage (see Harrison: [0003-0005], [0021-0024], Fig. 2) to be designed such that the neutral forming circuit comprises a semiconductor arrangement comprising a plurality of semiconductors (bidirectional switches <102-1,102-2>, see Harrison: [0022], [0037-0038], Fig. 2; see incorporated by reference Fornage: 2:13-61, Fig. 1 regarding each bidirectional switch implemented using pair of semiconductor n-mos transistors <102,104>), a plurality of capacitors including a first capacitor and a second capacitor (capacitors <204,206>), and an inductor (inductor <202>), wherein the semiconductor arrangement and the plurality of capacitors are connected in parallel between the first line conductor and the second line conductor, wherein the semiconductor arrangement comprises a first semiconductor branch and a second semiconductor branch, with the first semiconductor branch comprising a first number of the semiconductors and the second semiconductor branch comprising a second number of the semiconductors, and with a first node being positioned between the first semiconductor branch and the second semiconductor branch, wherein the first capacitor and second capacitor are positioned in series such that a second node exists between the first capacitor and the second capacitor, wherein the inductor is connected between the first node and the second node, and wherein the center point neutral reference voltage is output at the second node (see Harrison: [0021-0024], [0037-0038], Fig. 2, Fornage: 2:13-61, Fig. 1 regarding circuit arrangement of the neutral forming device arranged with the respective phase lines).
One of ordinary skill would appreciate that the neutral forming circuit of Harrison in view of Fornage presents a known AC/AC phase balancing circuit that is functionally equivalent to the balancing converter of Mu for forming a neutral voltage such that voltages on the split-phases are balanced for the loads. 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 system of Mu to incorporate the teachings of Harrison and Fornage by substituting the balancing converter of Mu with the known, functionally equivalent neutral forming circuit of Harrison for purposes of providing a known voltage balancing circuit receiving single phase AC predictably operating to convert single phase AC to single phase AC with neutral/split-phase when operating off grid (see Mu: 6:16-24, Fig. 3; see Harrison: [0003-0005], [0021-0024], Fig. 2).
Mu in view of Harrison, further in view of Fornage, teaches the general electrical circuit connection and operation of the neutral forming circuit/balancing converter to have common power lines <100A-C> coupled to grid breaker <108A-108B>, receive AC voltage without neutral from EVSE <110> on <100A,100C>, receive the AC voltage without neutral by balancing converter and output balanced AC voltage with neutral across lines <100A-C> to provide to loads <112A-C> respectively connected between respective pairs of the power lines (see Mu: Fig. 1 and detailed discussion above). Mu does not explicitly give further detail of common installation structure details to implement the circuit in a building load center, and with feature such as allowing the neutral forming converter to be selectively physically coupled to a branch of the main bus (see also rejection under 35 USC 112(a) above discussing the limitation). Ganger, however, teaches that it is known in the art of residential power systems having bidirectional EV charger capable of providing power during islanding and requiring separate neutral forming circuit (see Ganger: [0031], [0033-0034], [0045], Figs. 1, 4), the system including a main circuit breaker (utility facing breaker <22A>, see Ganger: [0034], Figs. 1, 4) structured to connect to a utility electrical grid (utility <26>) and comprising a main bus with L1, L2, and N lines (main panel <4> power lines <L1,L2,N,G>), to further provide a plurality of branches and branch circuit breakers (respective branch lines and breakers <22B-E>, see Ganger: [0034], [0045], Fig. 4) to selectively physically couple the respective main bus lines to the single-phase EV source (branch breaker <22C> for EV AC charger <8A>; see Ganger: [0034], [0045], Fig. 4), respective building loads (branch breakers <22D-E>) and also to the converter used to produce neutral when the system is islanded from the grid (branch breaker <22B> to converter providing neutral, see Ganger: [0030], [0033-0034], [0045], Fig. 4). One of ordinary skill would appreciate that Ganger teaches a known residential wiring arrangement using breaker panel that is similarly applicable for connecting the main power distribution bus to EV charger source, AC loads, and component providing neutral during islanding as similarly disclosed by Mu, and allowing controlled connection of components depending on the grid and power supply state (see Ganger: [0045], Fig. 4). 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 system of Mu in view of Harrison, further in view of Fornage, to incorporate the teachings of Ganger by providing respective branch arrangement and branch circuit breaker for selective physical coupling of the neutral forming converter as recited for purposes of providing known residential electrical wiring arrangement for AC sources, loads, and neutral providing circuit, that enable selective connection when the components are desired to be connected/disconnected from the power distribution system, such as ensuring the neutral providing component is connected when grid is disconnected and the EV source requiring neutral is connected to supply power (see Ganger: [0031], [0035], [0045], Figs. 1, 4).
Re claims 2-3. Mu in view of Harrison, further in view of Fornage, further in view of Ganger, teaches the neutral forming converter of claim 1, wherein the controller is configured to only activate the neutral forming circuit after confirming that the load center is islanded from a utility electrical grid (power grid <106>, see Mu: 6:36-63, Figs. 1, 4 regarding only starting power balancing after detecting grid is no longer connected and opening relays to power grid; see also similarly Ganger: [0045] regarding breakers to disconnect grid and connect neutral providing device); wherein the controller is configured to instruct the single-phase AC power source to supply power to the load center after confirming that the load center is islanded from the utility electrical grid (see Mu: 6:36-63, Figs. 1, 4 regarding controlling EVSE to supply power only after detecting grid is no longer connected and opening relays to power grid).
Re claim 4. Mu in view of Harrison, further in view of Fornage, further in view of Ganger, teaches the neutral forming converter of claim 1, and discloses the system inherently having respective control means, but does not explicitly discuss arrangement of the control means or how it is powered. Official Notice was previously taken and made of record that it is well-known in the art of single-phase AC power distribution management and control systems for the respective system controller to derive its power from available single-phase AC voltage. It would therefore have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to design the system of Mu in view of Harrison, further in view of Fornage, further in view of Ganger, such that the controller is configured to be powered by single-phase AC voltage for purposes of providing known, predictable means for electrically powering control electronics from the available AC power of the overall system.
Re claims 6-7, Mu in view of Harrison, further in view of Fornage, further in view of Ganger, teaches the neutral forming converter of claim 1, wherein the plurality of capacitors and the inductor form a filter inherently having a resonance frequency (inherent to arrangement, see Harrison: [0021-0024], [0037-0038], Fig. 2), wherein the semiconductor arrangement is configured to block current flow in both directions (see Harrison: [0021-0024], [0037-0038], Fig. 2, Fornage: 2:13-61, Fig. 1 regarding bidirectional switches), wherein the controller is configured to rapidly switch the plurality of semiconductors on and off at a frequency that exceeds the frequency of the single-phase AC voltage and exceeds the resonance frequency of the filter (see Harrison: [0016], [0020], [0024], Fig. 2 regarding switching frequency orders of magnitude/1000 times that of AC mains frequency; although explicit value of the resonance frequency of the filter is not made, it is implied that the switching frequency being significantly large by orders of magnitude and would be larger than resonance frequency; alternatively, one of ordinary skill would find it obvious to optimize the switching frequency and/or the resonance frequency such that the switching frequency is larger since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller, 105 USPQ 233. See also MPEP: 2144.05, II); wherein the first semiconductor branch comprises a first n-channel MOSFET and a second n-channel MOSFET, wherein the second semiconductor branch comprises a third n-channel MOSFET and a fourth n-channel MOSFET, wherein the drain terminal of the first n-channel MOSFET is connected to the first line conductor and the drain terminal of the second n-channel MOSFET is connected to the second line conductor, wherein the source terminal of the first n-channel MOSFET is connected to the source terminal of the second n-channel MOSFET, wherein the source terminal of the third n-channel MOSFET is connected to the source terminal of the fourth n-channel MOSFET, and wherein the drain terminal of the second n-channel MOSFET is connected to the drain terminal of the third n-channel MOSFET and to the first node (see Harrison: [0021-0024], [0037-0038], Fig. 2, Fornage: 2:13-61, Fig. 1 regarding circuit arrangement of the neutral forming device’s bidirectional switches/NMOS; note that terminals are indirectly connected, and also it is well-known and obvious that the drain/source sides may be reversed for a bidirectional switch circuit).
Re claim 9, the claim recites a load center comprising mostly the same components arranged and operated in the same manner as recited in claim 1, and therefore rejected by the same reasoning applied to claim 1 respectively above (see discussion of claim 1 above regarding respective teachings of the same corresponding components and obviousness reasoning). Note that the combination of Mu in view of Harrison, further in view of Fornage, further in view of Ganger, as discussed above further teaches the main circuit breaker structured to connect the main bus to a utility electrical grid (Mu: relays <108A-B> for connecting to power grid <106>, see Mu: 5:16-38, Figs. 1-3; see also similarly Ganger: [0034], [0045], Figs. 1, 4 regarding utility facing breaker <22A>), a first branch circuit breaker connected to a first branch of the plurality of branches and structured to electrically connect to a single-phase AC power source (see Ganger: [0034], [0045], Figs. 1, 4 regarding branch breaker <22C> for EV AC charger <8A>), and neutral forming converter selectively physically coupled to a second branch of the plurality of branches electrically connected to the first branch through the main bus (see Ganger: [0030], [0033-0034], [0045], Fig. 4 regarding branch breaker <22B> to connect main distribution bus to converter component providing neutral, and discussion of claim 1 above).
Re claims 10-12, 15-16, the further recited limitations essentially correspond to the limitations recited in claims 2-4, 6-7 and are therefore rejected by the same reasoning applied above.
Re claim 13. Mu in view of Harrison, further in view of Fornage, further in view of Ganger teaches the load center of claim 9, wherein the main circuit breaker comprises a controller, and wherein the controller is configured to actuate islanding of the main circuit breaker from the electrical grid (see Mu: 6:36-50, Fig. 1; Ganger: [0035], Figs. 1, 4 regarding control to island system from grid). Although Mu in view of Harrison, further in view of Fornage, further in view of Ganger does not explicitly disclose a separate second controller for the utility breaker (note Mu: 6:36-39 implies a separate control device may control grid connection), Official Notice was previously taken and made of record that it is well-known in microgrid power systems for the system to have multiple controllers with a respective one for control of the utility breaker. One of ordinary skill would appreciate that separation of control functions across multiple controllers is functionally equivalent if they still perform their respective functions. 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 system of Mu in view of Harrison, further in view of Fornage, further in view of Ganger to provide a second controller for controlling the main circuit breaker as recited for purposes of providing known, functionally equivalent control arrangement for operating separate components in a power system, that may be desirable depending on convenience of location/wiring of components or to work with preexisting components.
Response to Arguments
Applicant's arguments filed 19 June 2026 have been fully considered but they are not persuasive in light of new grounds of rejection addressing the amended claim limitations.
Regarding amendments made to claims 1, 9, see rejection under 35 USC 112(a) above regarding New Matter from claim limitations which do not appear to be supported by the original disclosure.
Regarding Applicant’s remarks regarding prior art rejection of claim 1, Applicant’s arguments are unpersuasive in light of the prior art teachings in combination as discussed in detail above. Applicant appears to argue that if Mu’s voltage lines <100A-C> are considered the main bus, Mu would have the balancing converter <114> always physically coupled to the lines and thus is not “selectively physically coupled”. First, it is noted that this limitation does not appear to be supported by Applicant’s original disclosure as discussed in the rejection under 35 USC 112(a). Second, it is noted that Ganger, which was previously applied to claim 9, appears to teach that it is known in the prior art for a load center system distributing power to building loads from an EV source lacking neutral during islanding of the system from the grid and providing separate converter component to provide the neutral, i.e. a system with similar components and function to Mu, for these components including the neutral forming converter equivalent to be coupled to the main bus via respective branch breakers to predictively provide a known way to interconnect the components to the residential load center distribution lines and allow for selective connection/disconnection of the components when appropriate.
Applicant appears to further allege that Mu’s neutral forming circuit is not structured to balance voltage across first and second load connected to other branches, but the allegation appears to misunderstand the function of Mu’s balancing converter. As discussed in the rejection above and in corresponding sections of Mu: 4:46-5:15, 5:39-6:24, Figs. 1-3, Mu’s converter functions to balance voltages regardless of the magnitude of loads differing across the power lines while the EVSE provides power. One of ordinary skill would readily understand that the loads depicted in Mu are merely representative of one or more loads present, and that Mu’s converter is disclosed as balancing the voltages regardless of how they would be connected. Harrison and Fornage further disclose the specific neutral forming converter circuit as a known, equivalent AC/AC converter design functioning as recited, and Ganger also gives further depiction of a residential system where the one or more loads receiving power from different combinations of the power lines corresponding to those shown in Mu would be connected via respective branch breakers. Applicant’s own disclosure does not otherwise appear to disclose a neutral forming circuit structured or operating in any way different than what has been disclosed by the prior art.
Applicant does not appear to provide further argument regarding the other independent claim 9, although Ganger discloses the relevant features as discussed, and does not appear to provide further argument regarding the dependent claim limitations.
Applicant is generally advised that the prior art appears to presently suggest that the main features of Applicant’s embodiments are known and obvious to those of ordinary skill in the art. In general, Mu would appear to suggest the overall system electrical circuit and function to provide a building power distribution system with separate neutral forming circuit that operates when the system is islanded from the grid and an EVSE without neutral provides power to the load. Harrison in view of Fornage teach the specific neutral forming circuit topology that predictively functions to balance and provide neutral for a power system in the same manner as the generic ones suggested by Mu. Ganger a system having similar circuit and operation to Mu, and gives a specific example arrangement for physically implementing the circuit in a building load center, i.e. by using branch breakers to connect each component to the respective L1, L2, N lines it needs to be connected to for receiving/providing power. At present it therefore remains unapparent what features of the application would be considered distinguished and nonobvious over the prior art. If Applicant wishes to further discuss the office action or the prior art, Applicant may contact the examiner as needed.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DAVID A SHIAO whose telephone number is (571)270-7265. The examiner can normally be reached Mon-Fri: 8:30AM-5:00PM.
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/DAVID A SHIAO/Examiner, Art Unit 2836
/REXFORD N BARNIE/Supervisory Patent Examiner, Art Unit 2836
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