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 Objections
Claims 1-6, 10-15, 18-20 objected to because of the following informalities:
Re claims 1, 3-6, 10, 12-15, 18, 20, the claims repeatedly make reference to “the determined voltage”, which is confusing because the independent claims introduce two separate elements, i.e. the DC to DC converter determined voltage and the at least one inverter determined voltage, using the same element name, and subsequent recitation does not clearly distinguish between the two. It is recommended the claims be amended to clearly describe which voltage is being referred to in each instance (e.g. “the voltage determined by the [DC to DC converter/at least one inverter]”, provide unique names for the elements, or provide other recitation that clearly distinguishes the two.
Re claims 2, 11, 19, the last two paragraphs refer to “a nominal voltage” twice, which is potentially confusing whether they intend to refer to two separate nominal voltages or the same nominal voltage. The claim should be amended to refer to “the nominal voltage” in the last paragraph if referring to the same value, or be given unique names if potentially different.
Re claims 5-6, 14-15, the phrase “determine…power level… based on a linear function” is somewhat vague given that no relation or details of the linear function with the power is recited. It is recommended the claim provide basic recitation of the relationship or details of the function to avoid confusion (e.g. “such that the [MVDC/MVAC] power level varies linearly with respect to the [DC to DC converter/at least one inverter] determined MVDC voltage” or similar).
Appropriate correction is required.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 9 rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Re claim 9, the term “about” is a relative term which renders the claim indefinite. The term “about” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. It is recommended the claim be amended to remove the phrase “about” (or specify exact error values if disclosed) and for purposes of examination the claim is interpreted as requiring a range of 100kW to 500kW.
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, 3-6, 8-10, 12-15, 17-18, 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kaufman (US2013/0328403), hereinafter Kaufman2013, in view of Suryanarayana (US2018/0166881), hereinafter Surya.
Re claim 1. Kaufman2013 teaches a solar power generation system (see Kaufman2013: Figs. 1-3) comprising:
at least one photovoltaic (PV) array (PV substrings <100/201>, see Kaufman2013: [0016], [0019], Figs. 1-2 regarding PV modules generating DC voltage) configured to generate low voltage direct current (LVDC) power (see discussion of obviousness of voltage ranges below);
at least one DC to DC converter (DC-DC converters <120/210>, see Kaufman2013: [0016], [0020], Figs. 1-2) electrically coupled to a medium voltage DC (MVDC) bus (DC bus <130/230>, see Kaufman2013: [0016], [0021], Figs. 1-2; see discussion of obviousness of voltage ranges below), said DC to DC converter configured to:
convert LVDC power received from the at least one PV array to MVDC power (see Kaufman2013: [0016], [0020-0021], Figs. 1-2);
determine a voltage of the MVDC bus (see Kaufman2013: [0029]); and
in response to the determined voltage exceeding a threshold output voltage, transmit the MVDC power via the MVDC bus at a DC power level less than a rated DC output power level of said at least one DC to DC converter (see Kaufman2013: [0029], Fig. 3A regarding DC-DC converters observing bus voltage and in response to bus voltage above threshold, e.g. 404V, linearly decreasing output below full rated power); and
at least one inverter (DC-to-AC inverter <140/239>, see Kaufman2013: [0016], [0024], Figs. 1-2) configured to:
receive the MVDC power from the at least one DC to DC converter (see Kaufman2013: [0016], [0024], Figs. 1-2);
convert the MVDC power to medium voltage AC (MVAC) power (see Kaufman2013: [0016], [0024], Figs. 1-2; see discussion of obviousness of voltage ranges below);
determine the voltage of the received MVDC power (see Kaufman2013: [0029-0030]); and
in response to the determined voltage being less than a threshold input voltage, transmit the MVAC power at an AC power level less than a rated AC output power level of said at least one inverter (see Kaufman2013: [0029-0030], Fig. 3B regarding inverter observing bus voltage and in response to bus voltage below threshold, e.g. 400V, decreasing its output drawn from the DC bus to below full rated power). See Kaufman2013: [0016], [0019-0021], [0024], [0029-0030], Figs. 1-3.
Although Kaufman2013 mentions that other operating voltages for the solar power generation system may be used (see Kaufman2013: [0019]), Kaufman2013 does not explicitly disclose examples using LVDC, MVDC, and MVAC, respectively. Surya, however, teaches that it is known in the art of solar power generation systems with PV arrays connected via DC/DC converters to DC bus to inverter to supply grid, that the system may be designed with voltage ranges such that the PV arrays provide LVDC power, the DC/DC converters convert LVDC to MVDC, and the inverters convert the MVDC to MVAC power (see Surya: [0005-0006], Fig. 1). One of ordinary skill would appreciate that the control functions of Kaufman2013 for having the DC-DC converter and inverter adjusting power level based on monitoring of DC bus may be equally applicable and beneficial to other known solar power generation systems with different nominal voltage ranges, such as that disclosed by Surya. 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 Kaufman2013 to incorporate the teachings of Surya by designing the system to use components operating with power in the respective LVDC, MVDC, and MVAC ranges as recited for purposes of adapting the system to other known, similar solar power generation systems which would predictably benefit from the power and voltage regulation strategy taught by Kaufman2013 (see Kaufman2013: [0019], [0029-0030], Figs. 1-3; Surya: [0005-0006], Fig. 1).
Re claim 3. Kaufman2013 in view of Surya teaches the solar power generation system of Claim 1, wherein said at least one DC to DC converter is further configured to, in response to the determined voltage being less than or equal to the threshold output voltage, transmit the MVDC power via the MVDC bus at the rated DC output power level of said DC to DC converter (see Kaufman2013: [0029], Fig. 3A regarding DC-DC converter output at full rated power when bus voltage below threshold, e.g. 404V).
Re claim 4. Kaufman2013 in view of Surya teaches the solar power generation system of Claim 1, wherein said at least one inverter is further configured to, in response to the determined voltage being greater than or equal to the threshold input voltage, transmit the MVAC power at the rated AC output power level of said inverter (see Kaufman2013: [0029-0030], Fig. 3B regarding inverter output at full rated power when bus voltage above threshold, e.g. 400V).
Re claim 5. Kaufman2013 in view of Surya teaches the solar power generation system of Claim 1, wherein said at least one DC to DC converter is further configured to determine an MVDC power level for transmitting the DC power when the determined MVDC voltage exceeds the threshold input voltage based on a linear function (see Kaufman2013: [0029], Fig. 3A regarding DC-DC converter output power decreasing linearly with voltage when bus voltage above threshold, e.g. 404V).
Re claim 6. Kaufman2013 in view of Surya teaches the solar power generation system of Claim 1, wherein said at least one inverter is further configured to determine the AC power level for transmitting the MVAC power when the determined MVDC voltage is less than the threshold input voltage based on a linear function (see Kaufman2013: [0029-0030], Fig. 3B regarding inverter output power increasing linearly with voltage when bus voltage below threshold, e.g. 400V).
Re claim 8. Kaufman2013 in view of Surya teaches the solar power generation system of Claim 1, wherein said at least one DC to DC converter is configured to: generate a power command based on a maximum power point tracking algorithm; and determine the DC power level at which to transmit MVDC power based in part on the generated power command (see Kaufman2013: [0016], [0018], [0020], Figs. 1-2 regarding DC-DC converter controller providing control signals for MPP tracking and corresponding power output).
Re claim 9. As best understood, Kaufman2013 in view of Surya teaches the solar power generation system of Claim 1. Although Kaufman2013 in view of Surya suggests the system may be designed for desired operating voltage ranges and any number of parallel power source branches (see Kaufman2013: [0019], Surya: [0005-0006], [0008]), Kaufman2013 in view of Surya does not give example DC output power level of the DC-DC converter as 100-500kW. Official Notice is hereby taken that it is known in the art of renewable power distribution systems for the system to be designed to have rated 100-500kW DC-DC converters given the operating power requirements/design of the system. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify or design the system of Kaufman2013 in view of Surya to have the rated DC output power level be in a range of 100 kilowatts to 500 kilowatts 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. One of ordinary skill would appreciate that respective power range may be chosen based on the capabilities or design of the power system generation scale, or if optimal for user’s application.
Re claim 10, the claim recites a method for controlling a solar power generation system comprising operating essentially the same components in the same manner as recited in claim 1, and is therefore rejected by the same reasoning applied respectively above.
Re claims 12-15, 17 the further recited limitations essentially correspond to the limitations recited in claims 3-6, 8, respectively, and are therefore rejected by the same reasoning applied above.
Re claim 18, the claim recites a solar power distribution system comprising essentially the same components operated in essentially the same manner as recited in claim 1, and is therefore rejected by the same reasoning applied respectively above.
Re claims 20 the further recited limitations essentially correspond to the limitations recited in claims 3, respectively, and are therefore rejected by the same reasoning applied above.
Claim(s) 2, 11, 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kaufman2013 in view of Surya, as respectively applied above, further in view of Kaufman (US2012/02993386), hereinafter Kaufman2012.
Re claim 2. Kaufman2013 in view of Surya teaches the solar power generation system of Claim 1, and although mentions other components may operate with the system (see Kaufman2013: [0034], Fig. 2), does not explicitly discuss operation with an energy storage system. Kaufman2012, however, teaches that it is known in DC bus power generation systems receiving power from PV array via DC-DC converter and outputting power via an inverter (see Kaufman2012: [0023-0024], [0038], Fig. 1A, 4) to further comprising an energy storage system (energy storage unit <130>, see Kaufman2012: [0024]) configured to: store MVDC power received from said DC to DC converter when a voltage of the MVDC bus is greater than a nominal voltage; and transmit MVDC power to said inverter when voltage of the MVDC bus is less than a nominal voltage (see Kaufman2012: [0029], [0033], Fig. 2C regarding energy storage storing power when above bus nominal voltage range and discharging energy when below bus nominal voltage range). 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 Kaufman2013 in view of Surya to further incorporate the teachings of Kaufman2012 by including an energy storage system operating as recited for purposes of providing further known DC bus interfacing power storage components to predictably enable coordinated storage and release of power to the DC bus to coordinate bus DC voltage control (see Kaufman2012: [0023], [0029], [0033], Figs. 1, 2C). Note the combination would teaches that the PV array coupled DC to DC converters are supplying the DC bus/energy storage while the at least one inverter is drawing power from the bus/energy storage in corresponding ranges.
Re claims 11, 19 the further recited limitations essentially correspond to the limitations recited in claims 2, respectively, and are therefore rejected by the same reasoning applied above.
Claim(s) 7, 16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kaufman2013 in view of Surya, as respectively applied above, further in view of Horio (US2021/0288504).
Re claim 7. Kaufman2013 in view of Surya teaches the solar power generation system of Claim 1, but does not explicitly discuss the inverter receiving curtailment signals, although such feature is generally well-known in grid-tied solar power generation systems. Horio, however, teaches that it is known in grid-tied solar power generation systems for the at least one inverter is configured to: receive a curtailment signal; and determine the AC power level at which to transmit power further based on the curtailment signal (see Horio: [0003], [0053], [0058], [0111], Figs. 1, 4 regarding receiving curtailment instruction signal and determining corresponding inverter AC power output level based thereon). 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 Kaufman2013 in view of Surya to incorporate the teachings of Horio for purposes of providing known control arrangement to allow the grid supplying inverter to be curtailed by utility services to comply with standard utility grid protocols and safety precautions (see Horio: [0003], [0053]).
Re claims 16 the further recited limitations essentially correspond to the limitations recited in claims 7, respectively, and are therefore rejected by the same reasoning applied above.
Conclusion
In summary, it is recommended Applicant consider the cited prior art of record which appears to teach that DC bus systems having PV DC-DC converters, grid-tied inverter, and energy storage monitor the DC bus voltage and adjust power to be below rated value when above/below respective thresholds to regulate DC bus voltage is known in the art. Further modifications of the system for MVDC/MVAC and other known solar power generation system features would also appear to be obvious to those of ordinary skill. At present it is not apparent what features of the disclosure would be distinguished and nonobvious over the prior art.
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
/DANIEL CAVALLARI/Primary Examiner, Art Unit 2836