Ex Parte Fornage

Patent Trial and Appeal Board

Jul 26, 2018

13853239 (P.T.A.B. Jul. 26, 2018)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR
13/853,239 03/29/2013 Martin Fornage
54698 7590 07/30/2018
MOSER TABOADA
1030 BROAD STREET
SUITE 203
SHREWSBURY, NJ 07702
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www .uspto.gov
ATTORNEY DOCKET NO. CONFIRMATION NO.
EE108 1057
EXAMINER
MATA,SARAM
ART UNIT PAPER NUMBER
2838
NOTIFICATION DATE DELIVERY MODE
07/30/2018 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
docketing@mtiplaw.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte MARTIN FORNAGE
Appeal2017-011345
Application 13/853,239
Technology Center 2800
Before JAMES C. HOUSEL, WESLEY B. DERRICK, and
JEFFREY R. SNAY, Administrative Patent Judges.
HOUSEL, Administrative Patent Judge.
DECISION ON APPEAL 1
Pursuant to 35 U.S.C. § 134(a), Appellant2 appeals from the
Examiner's decision finally rejecting claims 1-5, 7-12, and 14--19. 3 We
have jurisdiction over the appeal under 35 U.S.C. § 6(b ).
We REVERSE.
1 Our decision refers to the Specification (Spec.) filed March 29, 2013, the
Examiner's Final Office Action (Final) dated October 5, 2016, Appellant's
Appeal Brief (Appeal Br.) filed March 3, 2017, the Examiner's Answer
(Ans.) dated July 5, 2017, and Appellant's Reply Brief (Reply Br.) filed
September 5, 2017.
2 Appellant is the Applicant, Enphase Energy, Inc., which is identified in the
Appeal Brief as the real party in interest. Appeal Br. 4.
3 The Examiner has withdrawn this rejection with regard to claims 6, 13, and
20 (Ans. 8).
Appeal2017-011345
Application 13/853,239
STATEMENT OF THE CASE
The invention relates to a method and apparatus for providing
improved burst mode operation during power conversion (Spec. Title and
,r 1 ). The Inventor discloses that energy from solar panels or photovoltaic
(PV) modules can be used by employing a power conversion device, e.g.,
one or more inverters, to convert direct current (DC) from the PV modules
into an alternating current (AC) and couple this AC current to the
commercial power grid (id. ,r 3). However, the Inventor discloses that PV
modules have a nonlinear relationship between the current (I) and voltage
(V) they produce, wherein a maximum power point (MPP) on an I-V curve
identifies the optimal operating point of a PV module, i.e., the PV module
generates the maximum possible output power for a given temperature and
solar irradiance (id. ,r 4). Therefore, according to the Inventor, the power
conversion device coupled to the PV module employs a maximum power
point tracking (MPPT) technique to rapidly adjust operating current and
voltage in response to changes in temperature and solar irradiance so as to
continue operation of the PV module at the MPP (id.).
Nonetheless, Appellant discloses that when solar irradiance on a PV
module is low or changes from none to increasing or at initial activation, the
power conversion device will suffer from lower efficiency (Spec. ,r 5).
According to the Inventor, a PV module and power conversion device may
operate so inefficiently during low irradiance that it is best to deactivate the
PV module and/or power conversion device until solar irradiance increases
(id.). To address these issues, Appellant discloses operating the inverters in
"burst mode" during initial operation, wherein the inverters store energy
over a period of time, e.g., one or more AC grid voltage cycles ("energy
2
Appeal2017-011345
Application 13/853,239
storage periods"), and subsequently "burst" the stored energy to the
commercial power grid ("burst periods") (id. ,r 24). The Inventor teaches
that, in addition to improving the efficiency of the inverters, the burst mode
facilitates rapid convergence to the MPP (id. ,r 25). In some embodiments of
the invention, the Inventor teaches that full cycle bursts are produced by the
inverters, whereas in other embodiments, half cycle bursts are produced (id.
,r 36).
Claim 1, reproduced below from the Claims Appendix to the Appeal
Brief, is illustrative of the subject matter on appeal. The limitations at issue
are italicized.
1. A method for converting DC input power into AC output power
compnsmg:
operating a DC-AC inverter in a continuous mode, while
the DC input power is at a first level, wherein during the
continuous mode the DC input power is continuously converted
into AC output power and applied to an AC power grid; and
upon detecting the DC input power is at a second level,
operating the DC-AC inverter in a first burst mode, wherein
during the first burst mode a first period of energy storage is
immediately followed by a burst of AC output current generated
for half of a particular grid cycle and immediately followed by
a second period of energy storage, wherein each of the first and
the second periods of energy storage lasts an integer number of
grid voltage periods during which the DC-AC inverter does not
generate any output power.
Independent claims 8 and 15 recite an apparatus and system for
converting DC input power into AC output power including similarly
operating the DC-AC inverter in a first burst mode wherein a first period of
energy storage is immediately followed by a burst of AC output current
3
Appeal2017-011345
Application 13/853,239
generated for half of a particular grid cycle and immediately followed by a
second period of energy storage.
REJECTIONS
The Examiner maintains, and Appellant requests our review of, the
following grounds of rejection:
1. Claims 1-3, 5, 7-10, 12, 14--17, and 19 under 35 U.S.C.
§ I02(a)(l) as anticipated by Fomage '532; 4 and
2. Claims 4, 11, and 18 under 35 U.S.C. § 103 as unpatentable
over Fomage '532 in view ofFomage '383. 5
ANALYSIS
Rejection 1: Anticipation by Fornage '532
The dispositive issue before us on appeal is whether Appellant has
identified reversible error in the Examiner's finding that Fomage '532
teaches a first burst mode including a first period of energy storage
immediately followed by a burst of AC output current generated for half of a
particular grid cycle and immediately followed by a second period of energy
storage. The Examiner finds Fomage '532, Figure 4, waveform 402, shows
that a DC-AC inverter operates in a first burst mode wherein first period of
energy storage T 2 is immediately followed by a burst of AC output current
generated for half of a particular grid cycle T3 from 90°-270° and
immediately followed by a second period of energy storage T 4 (Final 3).
4 Fomage, US 2010/0091532 Al, published April 15, 2010 ("Fomage
'532").
5 Fomage et al., US 2009/0079383 Al, published March 26, 2009 ("Fomage
'383").
4
Appeal2017-011345
Application 13/853,239
The Examiner construes "immediately" to include an interim or transition
period (Ans. 3).
Appellant asserts that Fomage '532, Figure 4, depicts waveform 402
having energy storage period T 2 of one AC grid cycle followed by a burst of
current generated for an entire grid cycle T 3, followed by another energy
storage period T4 (Appeal Br. 10). In addition, Appellant asserts that
waveforms 404, 406 similarly depict energy storage periods of two or three
grid cycles with a full grid cycle burst between storage periods (id.).
Appellant argues Fomage '532 teaches full grid cycle bursts, not half cycle
bursts, immediately preceded by and followed by energy storage periods (id.
at 10-11 ). Appellant contends that the Examiner's interpretation of
"immediately" is inconsistent with the ordinary meaning of this term, which
is "without lapse of time; without delay; instantly" and "without interval of
time" (Reply Br. 2, citing dictionary.com6 and the Merriam-Webster
dictionary 7).
Appellant's argument is persuasive of reversible error. The Examiner
offers no authority for construing "immediately" to allow an interim or
transition period, whereas Appellant's proffer two definitions from
authoritative sources, both of which are consistent with the Specification and
figures. Moreover, although any full cycle burst includes two half cycle
bursts, the claims here require that the half cycle burst is immediately
preceded by and followed by energy storage periods. Fomage '532 clearly
teaches full cycle bursts immediately preceded by and followed by energy
6 http://www.dictionary.com/browse/immediately?s=t.
7 https://www.merriam-webster.com/dictionary/immediately.
5
Appeal2017-011345
Application 13/853,239
storage periods, wherein each half cycle of the full cycle burst is either
immediately preceded by or immediately followed by another half cycle
burst. As such, as Appellant contends, Fomage '532 does not teach a half
cycle burst immediately preceded by and followed by energy storage
periods. Accordingly, the Examiner's finding to the contrary is in error.
Anticipation is established when a single prior art reference discloses
all features of the claimed invention. In re Spada, 911 F.2d 705, 708 (Fed.
Cir. 1990). Here, Fomage '532 fails to teach operating a DC-AC inverter in
a first burst mode wherein a first period of energy storage is immediately
followed by a burst of AC output current generated for half of a particular
grid cycle and immediately followed by a second period of energy storage.
We, therefore, do not sustain the Examiner's anticipation rejection based on
Fomage '532.
Rejection 2: Obviousness over Fornage '532 in view of Fornage '383
The Examiner does not rely on Fomage '383 to remedy the deficiency
in Fomage '532 discussed above. Accordingly, for the same reason as given
above, we do not sustain the Examiner's obviousness rejection based on a
combination of Fomage '532 and Fomage '383.
DECISION
Upon consideration of the record, and for the reasons given above and
in the Appeal and Reply Briefs, the decision of the Examiner rejecting
claims 1-5, 7-12, and 14--19 is reversed.
REVERSED
6