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.
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.
Claim(s) 1-17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Briggs et al, US Pub. 2023/0322087, in view of Xu et al, CN 108631347.
Biggs et al disclose an isolation fault detection on DC charge bus comprising: a power system 10 includes a traction battery 12, a bussed electrical center 14, a DC charge bus 16, an auxiliary bus 18, and a traction bus 20; the bussed electrical center 14 is electrically connected between the traction battery 12, and the busses 16, 18, 20; the traction battery 12 includes a plurality of series connected cells 22; the bussed electrical center 14 includes positive and negative DC charge switches 24, 26, negative auxiliary switch 28, pre-charge resistor 30, pre-charge switch 32, and positive and negative main switches 34, 36; the positive and negative DC charge switches 24, 26 are components of the DC bus 16; the negative auxiliary switch 28 is a component of the auxiliary bus 18; the pre-charge resistor 32 and pre-charge switch 34 are series connected, and are in parallel with the positive main switch 36; the positive and negative main switches 34, 36 are components of the traction bus 20; the DC bus 16 is thus electrically connected with the traction bus 20 such that the positive and negative main switches 34, 36 are electrically between the traction battery 12 and DC bus 16, and the DC bus 16 terminates with a DC charge port 38; power flow between the on-board charger 44 and traction battery during AC charging, the controllers 48 command the negative auxiliary and pre-charge switches 28, 32 to close, followed by the positive main switch 3; power flow between the traction battery 12 and power electronics and electric machine 46, the controllers 48 command the pre-charge and negative main switches 32, 36 to close, followed by the positive main switch 34; provided the DC power source 40 is disconnected from the DC charge port 38, the controllers 48 may command the negative and positive DC charge switches 24, 26 to close, followed by the pre-charge and negative main switches 32, 36, and then the positive main switch 34; as such, the traction battery 12 and DC charge port 38 may be electrically connected, even though the DC power source 40 is disconnected from the DC charge port 38; during these operations, the controllers 48, may (or may not) prevent the power electronics and electric machine 46 from drawing power from the traction battery 12, as requirements dictate. (See Fig. 1A-B; par. 0019-0028
Regarding claims 1, 9, 13, Briggs et al disclose a vehicle including a traction battery and controlled switches, a DC charging port/path, an onboard AC charging arrangement, and a controller controlling the switches, during DC fast charging, the controller closes the pre-charge and main switches and thereafter the positive and negative DC charge switches, and during AC charging, the controller operates the auxiliary/pre-charge/main switches to connect the onboard charger and traction battery, but fail to disclose an AC filter capacitor pre-charge arrangement wherein the AC filter including a capacitor, and an AC enabling switch connected between the charge port and AC filter; and a controller programmed to, after the charge port is physically connected with a charge cord that is associated with a power source and before an electrical connection between the traction battery and power source is established, control at least some of the isolating, DC enabling, and AC enabling switches to permit pre-charging of the capacitor.
Xu et al disclose an energy feedback soft starting method and device of charging and discharging device comprising: a teaches sequentially connected AC-side soft-start circuitry, grid relays, capacitor circuitry, power-switch circuitry and DC-side soft-start circuitry; capacitors C1–C3 as AC filter capacitors; the controller activates PWM of the power-switch module to pre-charge those capacitors and thereafter closes grid relays RY1–RY3 when capacitor voltage has the required relationship to mains voltage; the sequence is as follows: pre-charge bus voltage; pre-charge capacitor module, determine whether capacitor voltage and mains voltage differ by less than a predetermined amount, and close the grid relay/DC-side circuitry. (See Figs. 1-4, 8-9; and the English translation).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to incorporate Xu's known AC-filter soft-start/pre-charge technique into Briggs et al vehicle AC charging circuitry in order to reduce current impact during grid connection and protecting inverter components. Such modification would cause the system to pre-charge the AC filter capacitor before completing the external AC electrical connection, thereby reducing inrush current during connection. Therefore, it would have been an obvious extension as taught by the prior art.
Regarding claim 2, in addition to the rejection of claims 1, 9, and 13 above, Briggs et disclose a vehicle traction battery electrically associated with the onboard charging/power-electronics system and controlled switching arrangements, while Xu et al teach DC-side energy coupled through a power-switch module for establishing the required capacitor/grid-side voltage. Using the already-connected traction battery as the DC energy source for inverter-driven AC-filter pre-charge would have been a predictable use of the existing battery/converter system to perform Xu et al pre-charge operation, eliminating the need for a separate pre-charge energy source. Therefore, it would have been an obvious extension as taught by the prior art.
Regarding claim 3, in addition to the rejection of claims 1, 9, and 13 above, Xu et al determines whether the filter-capacitor voltage differs from mains voltage by less than a predetermined voltage before closing the grid relay (see Figs. 2-3). Xu et al therefore require sensing/determination of the inverter/filter-side voltage for the disclosed comparison. Furthermore, it is to make sensor arrangement where sensing on the inverter side and grid side of the paralleling device to determine the voltage relationship before closure. It would have been obvious to place the voltage sensor at the filter side of the AC enabling relay to obtain the voltage information required for synchronization and safe relay closure. Therefore, it would have been an obvious extension as taught by the prior art.
Regarding claim 4, in addition to the rejection of claims 1, 9, and 13 above, having the controller commands the relay OFF and determines relay welding from an electrical/voltage detection result which an indication that relay contacts used in high-voltage/high-current EV charging can weld and that relay-weld detection is therefore required. Such is common and standard functions perform by controllers. It would have been obvious to apply this known relay-weld diagnostic to the AC enabling switch of the Briggs et al in view of Xu et al charging architecture. Once that switch is determined to be welded, preventing high-voltage DC charging through the shared charging interface would have been an expected protective response because the supposedly isolated AC circuitry would otherwise remain electrically exposed. Therefore, it would have been an obvious extension as taught by the prior art.
Regarding claim 5, in addition to the rejection of claims 1, 9, and 13 above, with respect to adding a second voltage sensor on the opposite side of the AC enabling switch, such limitation is just merely a duplication of element for which the inverter-side and grid-side voltages can be measured for synchronization before the parallel device closes. Therefore, it would have been an obvious extension as taught by the prior art.
Regarding claim 6, in addition to the rejection of claims 1, 9, and 13 above, Xu et al disclose establishing an AC voltage on the filter capacitor having the same characteristics as mains voltage, including matching phase and approximately matching magnitude. Briggs et al in view of Xu et al render the claim obvious.
Regarding claims 7 and 12, in addition to the rejection of claims 1, 9, and 13 above, with respect to closing the AC enabling switch such that closure coincides with a zero crossing of source voltage, such limitation is merely monitoring grid-side voltage and closing the parallel device at a zero crossing, which is a common function of the controller. It would have been obvious to employ the known zero-crossing closure technique for Briggs et al in view of Xu et al AC enabling relay to reduce switching transients. Therefore, it would have been an obvious extension as taught by the prior art.
Regarding claim 10, in addition to the rejection of claims 1, 9, and 13 above, Xu et al disclose pre-charging AC filter capacitors before closing the grid relay. Therefore, Briggs et al in view of Xu et al render the claim obvious.
Regarding claim 11, in addition to the rejection of claims 1, 9, and 13 above, Xu et al teach producing an AC filter voltage having substantially the same phase and magnitude as mains voltage. Therefore, Briggs et al in view of Xu et al render the claim obvious.
Regarding claim 14, in addition to the rejection of claims 1, 9, and 13 above, Xu et al teach precisely the relevant pre-connection sequence: PWM operation charges the AC filter capacitors; their voltage is compared/matched with grid voltage; and only thereafter is the grid relay closed (Fig. 2-3). Therefore, Briggs et al in view of Xu et al render the claim obvious.
Regarding claim 15, in addition to the rejection of claims 1, 9, and 13 above, Briggs et al provide the traction battery and associated power-electronics system, while Xu et al teach using the DC-side power-conversion circuitry to establish the AC-filter voltage. Using Briggs et al existing traction battery as the DC source for Xu et al inverter-driven pre-charge would have been an obvious implementation of the combined system. Therefore, Briggs et al in view of Xu et al render the claim obvious.
Regarding claim 16, in addition to the rejection of claims 1, 9, and 13 above, having the controller commands the relay OFF and determines relay welding from an electrical/voltage detection result which an indication that relay contacts used in high-voltage/high-current EV charging can weld and that relay-weld detection is therefore required. Such is common and standard functions perform by controllers. It would have been obvious to apply this known relay-weld diagnostic to the AC enabling switch of the Briggs et al in view of Xu et al charging architecture. Once that switch is determined to be welded, preventing high-voltage DC charging through the shared charging interface would have been an expected protective response because the supposedly isolated AC circuitry would otherwise remain electrically exposed. Therefore, it would have been an obvious extension as taught by the prior art.
Regarding claim 17, in addition to the rejection of claims 1, 9, and 13 above, Xu et al teach producing an AC filter voltage having substantially the same phase and magnitude as mains voltage. Therefore, Briggs et al in view of Xu et al render the claim obvious.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Albanna et al, US Pub. 2017/0036555, disclose a transformer less,7 current-isolated onboard charger with solid-state. Wang et al, US Pub. 2019/0148929, disclose a dual use vehicular generator.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DANIEL ST CYR whose telephone number is (571)272-2407. The examiner can normally be reached M to F 8:00-8:00.
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DANIEL ST CYR
Primary Examiner
Art Unit 2876
/DANIEL ST CYR/Primary Examiner, Art Unit 2876
