Ex Parte Virtanen

Patent Trial and Appeal Board

Sep 14, 2017

13624366 (P.T.A.B. Sep. 14, 2017)

United States Patent and Trademark Office
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
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
13/624,366 09/21/2012 Reijo Kalevi VIRTANEN OYAB-55 3239
129925 7590 09/18/2017
ABB Inc EXAMINER
Taft, Stettinius & Hollister LLP
One Indiana Square
NGUYEN, VIET P
Suite 3500
Indianapolis, IN 46204-2023
ART UNIT PAPER NUMBER
2831
NOTIFICATION DATE DELIVERY MODE
09/18/2017 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):
taft-ip-docket @ taftlaw. com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte REIJO KALEVI VIRTANEN
Appeal 2016-005054
Application 13/624,3 661
Technology Center 2800
Before CHRISTOPHER L. CRUMBLEY, N. WHITNEY WILSON, and
JULIA HEANEY, Administrative Patent Judges.
HEANEY, Administrative Patent Judge.
DECISION ON APPEAL2
Appellant requests review pursuant to 35 U.S.C. § 134(a) of the
Examiner’s Final Rejection of claims 1—14 of Application 13/624,366. We
have jurisdiction under 35 U.S.C. § 6(b). We affirm.
1 Appellant identifies the real party in interest as ABB Oy. App. Br. 3.
2 This Decision refers to the Specification filed Sept. 21, 2012, as amended
Oct. 9, 2014 (“Spec.”), Final Action dated Mar. 10, 2015 (“Final Act.”),
Appeal Brief dated Oct. 1, 2015 (“App. Br.”), Examiner’s Answer dated
Feb. 9, 2016 (“Ans.”), and Reply Brief dated Apr. 11, 2016 (“Reply Br.”).
Appeal 2016-005054
Application 13/624,366
BACKGROUND
The subject matter on appeal relates to controlling a cascade-fed
asynchronous generator in response to a network disturbance such as a
voltage dip. Spec. Tflf 2-4. A frequency converter connected between a rotor
of the generator and the network provides control by generating reactive
current in response to changes in the value of reactive current in the
network. Spec. 17. As described in the Specification, when reactive current
is fed via the stator of a cascade drive, a frequency converter in the rotor
circuit of the cascade drive is controlled to generate that part of the reactive
current which the stator circuit cannot generate, due to dynamic changes in
the network. Spec. 113. By using reactive current generated by the
frequency converter based on the difference between a base value and actual
value of reactive current, Appellant seeks to improve the efficiency and
accuracy of compensation provided by the dynamically inaccurate cascade
drive of the generator. Spec. H 20, 25.
Claim 1, reproduced below from the Claims Appendix of the Appeal
Brief, is illustrative of the subject matter on appeal:
1. A method for controlling a cascade-fed asynchronous
generator in connection with a voltage dip of a network fed by
the generator, wherein a frequency converter is connected
between a rotor of the asynchronous generator and the network,
by the method comprising:
measuring a magnitude of a voltage in the network;
calculating, on the basis of the voltage in the network, a base
value for reactive current to be fed to the network;
generating reactive current in the network by the generator;
measuring current of a stator of the generator;
determining an actual value of the reactive current in the
network;
2
Appeal 2016-005054
Application 13/624,366
calculating the difference between the base value and the actual
value of the reactive current;
providing the calculated difference to the frequency converter
to serve as an instruction in reactive current; and
generating reactive current in the network by the frequency
converter in accordance with the instruction in reactive current.
THE REJECTIONS
The Examiner maintains the following rejections on appeal:
1. Claims 1—3, 5—6, and 10-11 are rejected under 35 U.S.C. § 103(a)
as unpatentable over the combination of Hudson3 and Arlaban
Gabeiras.4 Final Act. 4.
2. Claims 4, 7—9, and 12—14 are rejected under 35 U.S.C. § 103(a) as
unpatentable over the combination of Hudson, Arlaban Gabeiras,
and Niiranen.5 Final Act. 6.
DISCUSSION
Appellant argues that the combination of Hudson and Arlaban
Gabeiras fails to teach the following steps as recited in claim 1:
“determining an actual value of the reactive current in the network;
“calculating the difference between the base value and the actual value of
the reactive current;” and “providing the calculated difference to the
frequency converter to serve as an instruction in reactive current.”
Appellant states that these features also are broadly encompassed in claim 5,
3 US 2007/0052244 A1 pub. Mar. 8, 2007 (“Hudson”).
4 US 2010/0219634 A1 pub. Sept. 2, 2010 (“Arlaban Gabeiras”).
5 About the Active and Reactive Power Measurements in Unsymmetrical
Voltage Dip Ride-through Testing, Oct. 24, 2007 (“Niiranen”).
3
Appeal 2016-005054
Application 13/624,366
the other independent claim on appeal, and does not separately argue any
dependent claims. App. Br. 6—10. All appealed claims therefore stand or
fall with claim 1. 37 C.F.R. § 41.37(c)(l)(iv) (2013).
Having considered Appellant’s arguments in light of this appeal
record, we are not persuaded that Appellant identifies reversible error.
Accordingly, we affirm the rejections for the reasons set forth in the Final
Action and Examiner’s Answer (Ans. 2-4), which we adopt as our own. We
add the following primarily for emphasis.
Hudson teaches controlling a cascade-fed generator by adjusting
current to the generator’s rotor when a voltage transient on a utility grid
occurs, in order to permit continued operation without disconnecting from
the grid. Hudson, Abstract. The Examiner relies on Hudson as teaching all
of the steps of claim 1, except for “generating reactive current in the network
by the frequency converter in accordance with the instruction in reactive
current.” Final Act. 5. The Examiner finds that Arlaban Gabeiras teaches
generating reactive current in the network by a frequency converter in
accordance with an instruction in reactive current. Id. (citing Arlaban
Gabeiras Figs. 1 and 3). The Examiner thus determines that it would have
been obvious to a person of ordinary skill in the art to use Arlaban
Gabeiras’s teaching of reactive power control in Hudson’s control system, in
order to reestablish voltage in the grid. Id. (citing Arlaban Gabeiras 146).
Appellant acknowledges that Arlaban Gabeiras teaches that reactive
current provided to the network is obtained from the difference between
reference or reactive power and actual reactive power, but argues that
Arlaban Gabeiras does not teach how the compensation is carried out using
both a generator and frequency converter. App. Br. 6—7. Appellant further
argues that Arlaban Gabeiras does not teach how reactive current is
4
Appeal 2016-005054
Application 13/624,366
measured and how a difference between the reference actual current is
generated using the frequency converter. App. Br. 7. The Examiner
responds by noting that Figs. 1 and 3 of Arlaban Gabeiras show how its
frequency converter 4 uses a reactive current instruction from control unit 6
to switch the rotor side converter and line side converter to produce reactive
power, and the reactive current instruction is the difference between
reference (Qref) and actual (Qout) reactive currents. Ans. 3. As a result, the
system produces both reactive power from the generator (Qs) and reactive
power from the frequency converter (Qc). Id. (citing Arlaban Gabeiras
125). Appellant does not dispute these findings.
Appellant’s argument that the Examiner erred in stating that the
claims do not recite that “compensation is carried out using both the
generator and the frequency converter” (Reply Br. 1—2 (citing Ans. 3)), is
not persuasive because it is based on a mischaracterization of the Examiner’s
reasoning. As the Examiner explains, the claims describe that the
compensation that refers to the calculated difference between the base value
and actual value of the reactive current is only sent to the frequency
converter, and not the generator. Ans. 3. Considered in the context of the
Examiner’s explanation, the Examiner’s statement concerning the
requirements of claim 1 is not reversible error.
Appellant further argues that the Examiner erred in relying on
Hudson’s and Arlaban Gabeiras’s teachings of reactive power to determine
obviousness of Appellant’s claims that recite reactive current, and fails to
provide reasoning to support the position that “comparison of reactive power
is a viable and obvious substitution for using a comparison of reactive
current as encompassed in Appellant’s claims.” App. Br. 8—9. The
Examiner responds by noting that the relationship between reactive current
5
Appeal 2016-005054
Application 13/624,366
and reactive power is known in the art and disclosed in Arlaban Gabeiras
137, which suggests using reactive current in place of reactive power for
calculations associated with voltage controls and grid voltage. Ans. 4. The
Examiner’s finding that the relationship between reactive current and power
was within the knowledge of a person of ordinary skill in the art is
reasonable, and supported by Arlaban Gabeiras 137. Accordingly,
Appellant’s argument is not persuasive of reversible error.
Appellant’s final argument that the “Examiner fails to appreciate that
using a comparison of reactive power as taught by the cited art would not
have realized the efficiency and accuracy provided by Appellant’s claimed
embodiment” (App. Br. 10) also is not persuasive of reversible error. The
fact that Appellant recognizes an advantage not recognized in the prior art
cannot be the basis for patentability where the advantage would flow
naturally from following the suggestion of the prior art. Ex parte Obiaya,
227 USPQ 58, 60 (BPAI 1985).
SUMMARY
We affirm the rejections of claims 1—14.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).
AFFIRMED
6