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 .
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 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).
Re claim 1. Mu teaches a neutral forming converter (gateway: <100>, see Mu: 3:50-65, 4:46-5:15, Figs. 1-3) structured for use with a single-phase power source (EVSE <110>, see Mu: 4:6-45, Fig. 1 regarding providing single phase AC power across lines <L1,L2>) in order to power loads connected to a load center (loads <112A-C>), the neutral-forming converter comprising:
a neutral forming circuit (balancing converter <114>) structured to receive as input a single-phase AC voltage across a first line conductor (grid line <L1/106A>)and a second line conductor (grid line <L2/106B>), the neutral forming circuit being configured to output the single-phase AC voltage with a center point neutral reference voltage (neutral <N/106C>), 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 and balanced split-phase AC to loads; note that Figs. 2-3 are both example embodiments of the balancing converter <114> that would be coupled to receive and output AC power from 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 circuit is structured such that, when a first load (load <112A>) is connected between the first line conductor and the center point neutral reference voltage and has a first impedance and a second load (load <112B>) is connected between the second line conductor and the center point neutral reference voltage and has a second impedance different from the first impedance, the voltage across the first load and the voltage across the second load are balanced (see Mu: 4:46-5:15, 5:39-6:24, Figs. 1-3 regarding design and operation of balancing converter <114> to balance the voltages between L1 and L2 with respect to neutral N even when the load values vary 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 branch and a second branch, with the first branch comprising a first number of the semiconductors and the second branch comprising a second number of the semiconductors, and with a first node being positioned between the first branch and the second 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).
Re claims 2-3. Mu in view of Harrison, further in view of Fornage, 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); 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, 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 hereby 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 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, 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 branch of the semiconductor arrangement comprises a first n-channel MOSFET and a second n-channel MOSFET, wherein the second branch of the semiconductor arrangement 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).
Claim(s) 9-13, 15-16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Mu ) 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 9. Mu teaches a load center (see Mu: Figs. 1-3), the load center comprising:
a main circuit breaker (relays <108A-B>) structured to connect to a utility electrical grid (power grid <106>) and comprising a main bus (grid lines <106A-C>; see Mu: 5:16-38, Figs. 1-3),
a single-phase AC power source (EVSE <110>, see Mu: 4:6-45, Fig. 1 regarding providing single phase AC power across lines <L1,L2>); and
a plurality of unique loads (loads <112A-C>, see Mu: 4:46-60, Fig. 1); and
a neutral forming converter (gateway: <100>, see Mu: 3:50-65, 4:46-5:15, Figs. 1-3), the neutral-forming converter being electrically connected to the single-phase AC power source (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 comprising:
a neutral forming circuit (balancing converter <114>) configured receive as input a single-phase AC voltage across a first line conductor (grid line <L1/106A>)and a second line conductor (grid line <L2/106B>), the neutral forming circuit being configured to output the single-phase AC voltage with a center point neutral reference voltage (neutral <N/106C>), 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 and balanced split-phase AC to loads; note that Figs. 2-3 are both example embodiments of the balancing converter <114> that would be coupled to receive and output AC power from lines <100A,B,C>/<L1,L2,N> as can be seen from Figs. 1-3 as discussed); and
a first 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 circuit is structured such that, when a first load (load <112A>) is connected between the first line conductor and the center point neutral reference voltage and has a first impedance and a second load (load <112B>) is connected between the second line conductor and the center point neutral reference voltage and has a second impedance different from the first impedance, the voltage across the first load and the voltage across the second load are balanced (see Mu: 4:46-5:15, 5:39-6:24, Figs. 1-3 regarding design and operation of balancing converter <114> to balance the voltages between L1 and L2 with respect to neutral N even when the load values vary from each other), and
wherein the neutral forming converter is structured to provide the center point neutral reference voltage to the main bus such that any circuit breaker connected to the main bus can connect to the center point neutral reference voltage (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 and balanced split-phase AC to loads via bus lines <106A-C> and to any breaker that could be connected thereto). 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 branch and a second branch, with the first branch comprising a first number of the semiconductors and the second branch comprising a second number of the semiconductors, and with a first node being positioned between the first branch and the second 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, does not explicitly discuss providing respective breakers for connecting to the single-phase AC power source and respective loads. 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 neutral forming circuit (see Ganger: [0031], [0033-0034] Figs. 1, 4) for the system to further include 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 (main panel <4> power lines <L1,L2,N,G>), a plurality of branch circuit breakers (breakers <22B-E>) connected to the main bus, the plurality of branch circuit breakers including: a first branch circuit breaker (breaker <22C>) structured to electrically connect to a single-phase AC power source (EV AC charger <8A>; see Ganger: [0034], Fig. 4); and a plurality of other branch circuit breakers (breakers <22E-D>, see Ganger: [0034], Fig. 4 regarding connection to corresponding single phase loads) that excludes the first circuit breaker, each other branch circuit breaker being structured to electrically connect to a unique load. One of ordinary skill would appreciate that Ganger teaches a known residential wiring arrangement that is similarly applicable for connecting the respective EV charger and AC loads to the main bus as disclosed by Mu. 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 circuit breaker arrangement as recited for purposes of providing known residential electrical wiring arrangement for AC sources and loads that enable selective connection when the components are desired to be connected/disconnected from the power distribution system (see Ganger: [0031], [0035], Figs. 1, 4). Note the combination results in the neutral-forming converter which is coupled to the main bus L1, L2, N lines as taught by Mu being connected to the first branch circuit breaker connecting the AC charger to the main bus when it provides power during islanding as discussed by both Mu and Ganger.
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 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 hereby 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 12 March 2026 have been fully considered but they are not persuasive.
Regarding Applicant’s arguments concerning amended claim 1, corresponding to previous prior art rejection of claim 5 in view of Mu, Harrison, and Fornage, Applicant’s arguments are not persuasive. Applicant appears to allege that Mu’s balancing converter 114 is a converter that inputs/outputs DC power on one side and outputs/inputs AC power with neutral on the other side, and therefore is not receiving single-phase AC to then output AC with neutral, and therefore would not be obvious to substitute with the balancing circuit of Harrison in view of Fornage. Applicant has not provided any citation to specific portions of the reference nor the Office action to support why Applicant has taken the alleged interpretation, nor does there to be any actual disclosure in Mu that lines up with Applicant’s alleged interpretation. It appears that most likely Applicant may have mistakenly misunderstood the disclosure regarding one of the example embodiments of the balancing converter 114 in Mu: Fig. 2.
As discussed in the prior art rejection previously presented and seen above, Mu: 4:46-5:15, Fig. 1 shows the overall connection arrangement of the balancing converter <114>, connected to respective AC lines 100A,B,C/L1,L2,N, with function to receive AC power without neutral from the EVSE (i.e. by EVSE lines 110A,B coupled to AC lines 100A,B/L1,L2) and then produce the balanced AC output with neutral (i.e. across lines 100A,B,C/L1,L2,N). Mu: Figs. 2-3 are then given as two example embodiments of the balancing converter <114>, with the rejection particularly noting the embodiment of Fig. 3’s AC-AC converter for convenience (see Mu: 6:16-24, Fig. 3). Applicant’s arguments make no discussion of the specific reasoning provided by the rejection or embodiment of Fig. 3, which has no mention at all of a DC terminal being required, and thus Applicant’s arguments fail to address the previously applied grounds of rejection. Furthermore, even if the example embodiment of Mu: Fig. 2 were applied though, it can be seen that the overall connection and function from Figs. 1-2 are the same, in that AC power is supplied from the EVSE, there is an intermediate DC terminal for balancing purposes that has no connection to the rest of the system as seen in Figs. 1-2, and then the balanced AC with neutral is produced to the split-phase AC loads (see Mu: 4:46-5:15, 5:39-6:15, Figs. 1-2). Applicant appears to have potentially misunderstood the embodiment of Fig. 2 as somehow having some kind of separate DC input side, while one of ordinary skill would instead understand from the disclosure of Mu that the embodiment of Fig. 2 still has the balancing converter receiving and outputting respective AC voltages from the rest of the system, with the shown DC side being an intermediate DC terminal (i.e. overall functions as AC-DC-split phase AC converter).
As discussed previously in the rejection, one of ordinary skill would thereby recognize that Harrison in view of Fornage discloses a specific AC-AC balancing converter arrangement that is functionally equivalent and may be connected in the exact same manner that is shown for the balancing converter <114> in Mu: Figs. 1, 3. Applicant’s argument that one of ordinary skill would not be motivated to combine Harrison and Fornage with Mu is not persuasive given that it appears to be based on Applicant’s misinterpretation that Mu’s balancing converter is some kind of DC-AC converter.
Applicant does not appear to provide any further arguments against the rejections applied to further limitations and dependent claims.
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 discuss the reasoning of the rejection and disclosure of the prior art, Applicant may contact the examiner as needed.
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.
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.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Rexford Barnie can be reached at (571) 272-7492. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/DAVID A SHIAO/Examiner, Art Unit 2836
/REXFORD N BARNIE/Supervisory Patent Examiner, Art Unit 2836
Prosecution Insights