Ex Parte KehrliDownload PDFBoard of Patent Appeals and InterferencesDec 12, 201110658597 (B.P.A.I. Dec. 12, 2011) Copy Citation UNITED STATES PATENT AND TRADEMARK OFFICE ________________ BEFORE THE BOARD OF PATENT APPEALS AND INTERFERENCES ________________ Ex parte ARNOLD P. KEHRLI ________________ Appeal 2009-013997 Application 10/658,597 Technology Center 2800 ________________ Before ALLEN R. MacDONALD, GREGORY J. GONSALVES, and JASON V. MORGAN, Administrative Patent Judges. MORGAN, Administrative Patent Judge. DECISION ON APPEAL Appeal 2009-013997 Application 10/658,597 2 STATEMENT OF THE CASE Introduction 1 This is an appeal under 35 U.S.C. § 134(a) from the Examiner‘s final rejection of claims 1, 3 – 11, 13 – 15, and 19 – 23. We have jurisdiction under 35 U.S.C. § 6(b). We affirm. Invention The invention relates to power flow regulation for utility power systems (Spec. 1). Independent claims 1 and 23 are directed to multi-line utility power transmission systems comprising first and second power transmission lines and a power flow controller. Independent claim 10 is directed to a method of regulating such power transmission systems. Exemplary Claim 1. A multi-line utility power transmission system comprising: a first power transmission line having a first impedance characteristic; a second power transmission line including a superconductor, in parallel with the first power transmission line, and having a second impedance characteristic less than the first impedance characteristic; and a power flow controller, coupled to the second power transmission line, for selectively regulating 1 For purposes of this appeal, we refer to the Examiner‘s Final Rejection, June 10, 2008 (Fin. Rej.), Appellant‘s Appeal Brief, November 3, 2008 (App. Br), Appellant‘s Amendments to the Appeal Brief, December 23, 2008 (Amend. App. Br), the Examiner‘s Answer, March 20, 2009 (Ans.), and Appellant‘s Reply Brief, April 24, 2009 (Reply Br.). Appeal 2009-013997 Application 10/658,597 3 during normal operating conditions of the power transmission system by a variable amount at least one of the magnitude and direction of the power flowing through the second power transmission line; wherein the power flow controller is configured to selectively regulate the power flowing through the second power transmission line to provide at least one of load balancing between the first power transmission line and the second power transmission line and flow optimization between the first power transmission line and the second power transmission line; wherein the power flow controller is configured to provide incremental flow change of current. (Emphases added). Evidence Examiner Relies Upon Parton 4,045,823 Aug. 30, 1977 Hingorani 5,420,495 May 30, 1995 Talisa 5,878,334 Mar. 2, 1999 Couture US 2002/0005668 A1 Jan. 17, 2002 Morita US 6,344,956 B1 Feb. 5, 2002 Sinha US 2003/0183410 A1 Oct. 2, 2003 (filed Sept. 14, 2001) Shimomura JP 11122793 A Apr. 30, 1999 Examiner’s Rejection The Examiner rejects claims 1, 3, 5, 7, and 23 2 under 35 U.S.C. § 103(a) as being unpatentable over Sinha and Morita. 2 Claim 23 was introduced in an Amendment After Final, July 8, 2008. The Examiner entered claim 23, but indicated in an Advisory Action, August 7, 2008, that the claim was rejected based on findings previously used to reject claims 16 – 18, now canceled. These findings relied on the teachings and suggestions of Sinha and Morita (Fin. Rej. 2 – 3 and 5 – 7). Moreover, Appellant submits that claim 23 is rejected under 35 U.S.C. § 103(a) as being unpatentable over Sinha and Morita (Amend. App. Br. 2; Reply Br. 3). Appeal 2009-013997 Application 10/658,597 4 The Examiner rejects claim 4 under 35 U.S.C. § 103(a) as being unpatentable over Sinha, Morita, and Talisa. The Examiner rejects claim 6 under 35 U.S.C. § 103(a) as being unpatentable over Sinha, Morita, and Shimomura. The Examiner rejects claims 8 – 11, 13, 14, and 22 under 35 U.S.C. § 103(a) as being unpatentable over Sinha, Morita, and Hingorani. The Examiner rejects claim 15 under 35 U.S.C. § 103(a) as being unpatentable over Sinha, Morita, Hingorani, and Shimomura. The Examiner rejects claims 19 and 20 under 35 U.S.C. § 103(a) as being unpatentable over Sinha, Morita, and Parton. The Examiner rejects claim 21 under 35 U.S.C. § 103(a) as being unpatentable over Sinha, Morita, and Couture. ISSUES Did the Examiner err in finding that Morita teaches or suggests a power transmission system power flow controller for selectively regulating by a variable amount at least one of the magnitude and direction of the power flowing through a power transmission line, as recited in claim 1? Did the Examiner err in finding that Morita teaches or suggests that the power flow controller is configured to provide incremental flow change of current, as recited in claim 1? Did the Examiner err in finding that Morita teaches or suggests that the power flow controller selectively regulates power flow during normal operating conditions of the power transmission system, as recited in claim 1? Did the Examiner err in finding that it would have been obvious to an artisan of ordinary skill to combine the teachings and suggestions of Sinha and Morita? Appeal 2009-013997 Application 10/658,597 5 FINDINGS OF FACT 1. Morita teaches that: superconductive/normal conductive transition-type current-limiting devices most directly utilize the superconduction/normal conduction transition properties of superconductors. When carrying a load current, the current flowing to the superconductor is never greater than the critical current, and therefore the resistance of the superconductor is extremely low. In the event of a short-circuit accident, however, the current flowing to the superconductor exceeds the critical current, and the heat generated thereby causes transition of the superconductor from a superconductive state to a normal conductive state, thus generating electrical resistance. This resistance limits the fault current. (Col. 1, ll. 44 – 55). 2. Morita teaches that: [b]y applying an external magnetic field it is possible to generate a larger Rf in the current-limiting element even at the same conduction current value. This raises the entire current-limiting element above the critical temperature more rapidly, thus avoiding local damage by local quenching and allowing the necessary electrical resistance to be generated. (col. 7, ll. 12 – 17). PRINCIPLES OF LAW Claim construction During ex parte prosecution, the USPTO determines the scope of the claims by giving the language the ―broadest reasonable construction ‗in light of the specification as it would be interpreted by one of ordinary skill in the art.‘‖ Phillips v. AWH Corp., 415 F.3d 1303, 1316 (Fed. Cir. 2005) (en banc) Appeal 2009-013997 Application 10/658,597 6 (quoting In re Am. Acad. of Sci. Tech. Ctr., 367 F.3d 1359, 1364 (Fed. Cir. 2004)). Obviousness ―[R]ejections on obviousness grounds cannot be sustained by mere conclusory statements; instead, there must be some articulated reasoning with some rational underpinning to support the legal conclusion of obviousness.‖ KSR Int’l Co. v. Teleflex, Inc., 550 U.S. 398, 418 (2007) (internal quotations and citation omitted). ANALYSIS Claim 1 Selectively regulating by a variable amount Appellant contends, ―Morita‘s current-limiting element clearly provides a substantial, non-incremental change in current; it is not configured to provide incremental change in current, nor can it regulate the power flow by a variable amount‖ (App. Br. 9) (emphasis added). Appellant argues that this is ―because the operation of Morita‘s current-limiting element is based on a large change in resistance as a result of quenching from superconductivity to normal conductivity‖ where the change ―in resistance results in a . . . well-defined reduction in the flow of power‖ (id.). The Specification does not provide a clear definition for the limitation ―variable.‖ Absent a clear definition, we apply the broadest reasonable interpretation. Here, ―variable,‖ as broadly claimed, includes something that is not fixed. The Examiner finds that in Morita the ―increase in resistance limits the current (and in turn, the power) by an incremental and variable amount depending upon the amount of current that was flowing initially and the Appeal 2009-013997 Application 10/658,597 7 increase in resistance level‖ (Ans. 4). We find that the Examiner‘s reasoning—that the current flowing during normal conductivity would depend on the current flowing during superconductivity—is reasonable. Furthermore, Morita discloses that current-limiting devices generate electrical resistance when ―the current flowing to the superconductor exceeds the critical current‖ (FF 1) (emphasis added). This means that the current flowing through such devices for them to enter a normal conductive state merely must exceed the critical current threshold, rather than being fixed. As such, in Morita both the initial current and the limited-current that follows are unfixed (i.e., variable). Therefore, we agree with the Examiner that Morita teaches or suggests the claimed selectively regulating by a variable amount. Incremental flow change of current Appellant contends that ―Morita‘s transition from superconductive power flow to normal power flow is non-incremental; rather, it is sudden and induces a significant change in resistance‖ (App. Br. 8) (emphasis added). Appellant submits that ―Morita‘s current-limiting element ostensibly has only two states of resistance‖ (App. Br. 8) where a sudden transition from a superconducting state to a normal-conducting state ―results in a step- like, non-incremental change in power flow‖ (App. Br. 9). The Specification discloses coupling a phase angel regulator with a superconducting line if ―finer incremental flow change is desired‖ (Spec. 7) (emphasis added). However, this disclosure falls short of providing a clear definition for the term ―incremental.‖ Absent a clear definition, we apply the broadest reasonable interpretation. Since the Specification does not specify a minimum number of steps needed for power flow change to be considered Appeal 2009-013997 Application 10/658,597 8 ―incremental,‖ we find that, as broadly claimed, ―incremental‖ includes a power flow change of only a single step. Morita teaches current-limiting devices in which heat causes transition of the superconductor from a superconductive state to a normal conductive state, creating current-limiting resistance (FF 1). This produces at least one step of (i.e., incremental) flow change of current. Normal operating conditions Appellant contends that ―Morita‘s current-limiting element does not play any role during normal operating conditions of the power transmission system‖ because ―Morita discloses a current-limiting element that operates only upon detection of a fault‖ (App. Br. 10) (emphases added). Appellant identifies descriptions in the Specification of some conditions in which the claimed invention can operate (Reply Br. 5 – 6). However, these descriptions fall short of providing a clear definition of ―normal operating conditions.‖ As such, we apply the broadest reasonable interpretation. The Examiner finds that ―normal operating conditions‖ can mean ―whenever current is flowing through said superconductor‖ (Ans. 8). We agree with Appellant (Reply Br. 5) that this claim construction is unreasonably broad. However, we do not read ―normal operating conditions‖ so narrowly as to preclude any fault from being detected and managed. Instead, we construe ―normal operating conditions‖ as meaning ―whenever current is flowing through the transmission system at a rate that can be managed such that damage to the transmission system is avoided.‖ Morita teaches applying an external magnetic field to raise the current-limiting element to a critical temperature more rapidly, thus Appeal 2009-013997 Application 10/658,597 9 avoiding local damage by local quenching (FF 2). Because local damage is avoided, the current flowing through the system at the time of quenching is current flowing at a rate that can be managed (through quenching) such that damage to the transmission system is avoided. Appellant contends that the quenching in Morita does not occur during normal operating conditions because Morita teaches applying a magnetic field after detecting abnormal current (App. Br. 11). However, because such currents can be managed while avoiding damage to the transmission system, we find that ―normal operating conditions‖ does not preclude detecting abnormal current. Sinha and Morita Appellant contends that ―coupling a power flow controller to a second power transmission line including a superconductor (such as Sinha‘s superconducting transmission line) is counterintuitive since doing so could decrease the level of power flow through the lower impedance second power transmission line‖ (App. Br. 12). However, Morita‘s current-limiting device includes a state in which the superconductor is in a superconductive state (FF 1). Since the level of power flow would not decrease during this state, we do not agree with Appellant that combining Sinha and Morita would have been counterintuitive. Furthermore, Appellant‘s arguments are not responsive to the Examiner‘s articulated reasoning that ―[i]t would have been obvious to one of ordinary skill in the art at the time of the invention to add a reactor onto the superconductor transmission line of Sinha‘s invention to regulate the power flow through the line and also reacts [sic] quickly to short-circuit accidents‖ (Ans. 4) (emphasis added). Morita teaches the use of current- Appeal 2009-013997 Application 10/658,597 10 limiting devices for use ―[i]n the event of a short-circuit accident‖ (FF 1). This shows that the Examiner‘s reasoning as to why the combination of Morita and Sinha would have made obvious the claimed invention has a rational underpinning. Appellant disputes (Reply Br. 7) the Examiner‘s statement that ―Morita does teach his power flow controller being coupled to a superconducting cable‖ (Ans. 9). However, even if Morita alone would not have taught or suggested such coupling, the combination of Morita and Sinha—which we agree with the Examiner would have been obvious— would have taught or suggested such coupling. For at least the reasons discussed above, we find no error in the Examiner‘s rejection of claim 1 under 35 U.S.C. § 103(a) as being unpatentable over Morita and Sinha. Claims 3 – 9 and 19 – 22 Appellant makes the same arguments with respect to claims 3 – 9 and 19 – 22, which depend from claim 1 (App. Br. 7 and 13). Accordingly, for the reasons discussed above, we find the Examiner did not err in rejecting claims 3 – 9 and 19 – 22. Claims 10, 11, and 13 – 15 Appellant‘s arguments for claim 10 (App. Br. 13 – 14) are similar to those made for claim 1 (App. Br. 7 – 13). Accordingly, for the reasons discussed above, we find the Examiner did not err in rejecting claim 10. Appellant groups claims 10, 11, and 13 – 15 together (App. Br. 13 – 14). As such, we find that claim 10 is representative of, and find no error in the Examiner‘s rejection of, claims 11 and 13 – 15. Appeal 2009-013997 Application 10/658,597 11 Claim 23 Appellant‘s arguments for claim 23 (App. Br. 14 – 15) are similar to those made for claim 1 (App. Br. 7 – 13), except that claim 23 does not include the incremental flow change of current limitation. Accordingly, for the reasons discussed above, we find the Examiner did not err in rejecting claim 23. CONCLUSIONS 1. The Examiner did not err in finding that Morita teaches or suggests a power flow controller for selectively regulating a power transmission system by a variable amount at least one of the magnitude and direction of the power flowing through a power transmission line, as recited in claim 1. 2. The Examiner did not err in finding that Morita teaches or suggests that the power flow controller is configured to provide incremental flow change of current, as recited in claim 1. 3. The Examiner did not err in finding that Morita teaches or suggests that the power flow controller selectively regulates power flow during normal operating conditions of the power transmission system, as recited in claim 1. 4. The Examiner did not err in finding that it would have been obvious to an artisan of ordinary skill to combine the teachings and suggestions of Sinha and Morita. 5. The Examiner did not err in rejecting claims 1, 3 – 11, 13 – 15, and 19 – 23 under 35 U.S.C. § 103(a). Appeal 2009-013997 Application 10/658,597 12 DECISION We affirm the Examiner‘s decision rejecting claims 1, 3 – 11, 13 – 15, and 19 – 23. No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a)(1)(iv). AFFIRMED ke Copy with citationCopy as parenthetical citation