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 .
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 07/26/2024 is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
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.
Claims 1, 6, 8, 10-11 & 16-19 are 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.
Claim 1 recites “measuring a voltage over three current transformers, using the voltage for determining a sum current”, and “wherein that filtering the voltage with a low-pass filter and a high-pass filter.” The claim does not clearly specify whether the filtering occurs before or after determining the sum current, nor does it clearly identify whether the “voltage” being filtered is the raw measured voltage across the transformers, a voltage representing the determined sum current, or another derived signal. Because the claim fails to clearly define the signal being processed and the sequence of operations, the metes and bounds of the method cannot be determined with reasonable certainty. Additionally, the phrase “wherein that filtering” is grammatically unclear and does not clearly indicate whether filtering is an additional required step or merely explanatory language, further contributing to ambiguity.
Claims 8 and 16 recite that “the high-pass signal voltage is used to acquire information about partial discharges.” The claims do not define what constitutes “information,” what parameters are acquired, or what processing is required to distinguish partial discharges from other high-frequency transients. Without objective boundaries defining the claimed acquisition of information, one of ordinary skill in the art cannot determine the scope of the limitation with reasonable certainty. Accordingly, claims 8 and 16 are indefinite under 35 U.S.C. 112(b).
Claim 11 recites corresponding apparatus limitations using substantially parallel language and includes “wherein that the apparatus is configured to: filter the voltage.” The claim does not clearly specify which structural component performs the filtering or whether the filtering is performed by the calculation unit or by separate structure. As in claim 1, the antecedent basis and identity of “the voltage” being filtered are unclear. Because the functional relationships among the recited components and the signal flow are not defined with reasonable clarity, claim 11 is indefinite.
Claim 19 recites “wherein, upon receiving the data pertaining to the fault conditions, by the remote device,” but does not recite any further action, function, or result performed by or at the remote device upon receipt of the data. The limitation introduces a conditional clause without specifying what occurs after the stated condition is satisfied. Because no operative step or structural consequence is defined, the scope of the claim cannot be determined with reasonable certainty. Accordingly, claim 19 is indefinite.
Dependent claims 6, 10 and 17-19, not specifically addressed, are rejected for dependence on a rejected parent claim.
Appropriate correction is required.
Claim Rejections - 35 USC § 103
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, 6, 8, 10-11 & 16-19 is/are rejected under 35 U.S.C. 103 as being unpatentable over Mulders et al. (US 2020/0241064 A1) in view of Kojovic et al. (US 2006/0012374 A1).
Regarding claim 1, Mulders et al. disclose, a method of measuring a current for fault detection in a distribution grid (current measurement and ground fault detection system for multi-phase power system [0018], [0021], [0036]), the method comprising: installing three current transformers in series on three phase conductors by winding the three current transformers in a non-intrusive manner around a first phase, a second phase, and a third phase (plurality of phase current measurement coils 202A, 202B, 202C detecting currents of respective phases [0023], connected in series on secondary side [0025]; under broadest reasonable interpretation, phase current measurement coils coupled to respective phase conductors inherently surround or are positioned around the conductors to detect current), measuring a voltage over the first current transformer the second current transformer and the third current transformer (voltage drop across shunt resistors associated with each coil [0026], differential amplifier detecting voltage drop [0027]), and using the voltage for determining a sum current (ground fault detection circuit measuring summation of currents via series connected coils [0025], [0036]); wherein that filtering the voltage with a low-pass filter (low pass filter 306 and 406 [0027], [0028]).
Mulders et al. do not explicitly disclose filtering the voltage with a high-pass filter to receive a high-pass signal voltage; using the high-pass signal voltage to determine the fault transients in the sum current at fault occurrence; and using the sharp edges of the high-pass signal voltage to synchronize a start time of travelling wave pulses.
Kojovic et al. disclose that, to reliably detect and time tag arrival of a traveling wave current pulse, the traveling wave current pulse is filtered out from the current component corresponding to the fundamental power frequency (e.g., 60 Hz) ([0036]) (under broadest reasonable interpretation, filtering out the fundamental frequency corresponds to isolating high-frequency transient components consistent with high-pass filtering). Kojovic et al. further disclose that Rogowski coils detect high-frequency transient current changes proportional to di/dt ([0037]) and that when the output exceeds a threshold, a tracking pulse is generated for timing logic to determine fault location using arrival times of traveling waves ([0042]). Kojovic et al. also disclose synchronization of arrival times using a GPS reference time signal ([0041]).
It would have been obvious to one skilled in the art to modify Mulders et al. to include high-frequency transient filtering and edge-based traveling wave timing as taught by Kojovic et al., because Mulders already measures a summation current indicative of fault conditions, and Kojovic teaches that isolating high-frequency components and using their sharp rising edges enables rapid and accurate fault detection and location (see Kojovic’s pars. [0036] & [0042]), thereby improving speed and diagnostic precision of multi-phase fault detection systems.
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Regarding claim 6, Mulders et al. & Kojovic et al. disclose the method according to claim 1, wherein Mulders et al. further disclose low-pass filters 306 and 406 configured to filter detected voltage signals to obtain an average voltage level associated with the fundamental power frequency component (see low pass filter 306, 406, paragraphs [0027]–[0028]). Under the broadest reasonable interpretation, filtering to obtain the averaged fundamental component corresponds to passing signals below the power system frequency range (e.g., below 150 Hz).
Mulders et al. do not explicitly disclose that the high-pass filter passes signals higher than 1 kHz.
Kojovic et al. disclose the high-pass filter passes signals higher than 1 kHz (see [0042]; wherein traveling wave current pulses are high-frequency transients superimposed on the fundamental 60 Hz component and that Rogowski coils operate over a wide frequency range up to over 1 MHz and are particularly sensitive to high-frequency components, also see [0037] & [0046], wherein, isolating traveling wave components inherently requires passing frequencies significantly higher than the fundamental frequency, including frequencies in the kilohertz range and above).
It would have been obvious to select cutoff frequencies such that the low-pass filter passes signals lower than 150 Hz and the high-pass filter passes signals higher than 1 kHz in order to separate fundamental frequency components from high-frequency transient components, as such filter selection constitutes routine signal conditioning design consistent with Kojovic’s disclosure of high-frequency transient detection (see Kojovic’s paragraphs [0037], [0046]).
Regarding claim 8, Mulders et al. & Kojovic et al. disclose the method according to claim 1, wherein Mulders et al. further disclose Mulders et al. disclose measuring summed phase currents for ground fault detection (paragraphs [0025], [0036]) and filtering signals to process current measurements (paragraphs [0027]–[0028]).
Mulders et al. do not explicitly disclose that the high-pass signal voltage is used to acquire information about partial discharges.
Kojovic et al. disclose that the high-pass signal voltage is used to acquire information about partial discharges ( see [0018, wherein faults generate high-frequency traveling wave currents that propagate through the system, Rogowski coils detect rapid current changes proportional to di/dt, see paragraph [0037], and that high-frequency transients are superimposed on the 60 Hz fundamental component).
It would have been obvious to use the high-frequency component of the measured signal in Mulders to acquire information about partial discharge-related phenomena because Kojovic explicitly teaches that high-frequency current transients are indicative of fault events and are detectable using Rogowski coils over a wide frequency range (see Kojovic’s paragraphs [0037] & [0046]), thereby enabling identification of fault-related discharge activity in a power system.
Regarding claim 10, Mulders et al. disclose the method according to claim 1, wherein phase current measurement coils 202A, 202B, 202C positioned to detect phase currents (paragraph [0023]).
Mulders et al. do not explicitly disclose that at least one of the three current transformers is a Rogowski coil.
Kojovic et al. disclose that a Rogowski coil is positioned around a transmission line conductor to detect traveling wave currents (paragraph [0036]), that Rogowski coils are wound around a non-magnetic core and placed around conductors (paragraph [0036]), and that Rogowski coils are particularly suitable for detecting rapid current changes and high-frequency components (paragraph [0037]).
It would have been obvious to use the high-frequency component of the measured signal in Mulders to acquire information about partial discharge-related phenomena because Kojovic explicitly teaches that high-frequency current transients are indicative of fault events and are detectable using Rogowski coils over a wide frequency range (paragraphs [0037], [0046]), thereby enabling identification of fault-related discharge activity in a power system.
Regarding claim 11, Mulders et al. disclose an apparatus for measuring current for fault detection in a distribution grid (current measurement and ground fault detection system/circuitry 200, paragraph [0018]); three current transformers arranged to be installed in series on three phase conductors by winding the three current transformers in a non-intrusive manner around a first phase, a second phase, and a third phase when in use (phase current measurement coils 202A, 202B, 202C detecting respective phase currents of a multi-phase system, paragraph [0023]; secondary coils connected in series to measure summation, paragraph [0025]; coils positioned around conductors under BRI); a measurement unit configured to measure a voltage over the first current transformer, the second current transformer and the third current transformer (differential amplifiers 302 detecting voltage drop across shunt resistors 204 coupled to coils 202A–202C, paragraphs [0026]–[0027]); and a calculation unit configured to use the measured voltage to determine a sum current (ground fault detection circuit 400 measuring summation of currents across series-connected coils 202A–202C, paragraphs [0025], [0036]); wherein that the apparatus is configured to filter the voltage with a low-pass filter and a high-pass filter to receive a low-pass signal voltage and a high-pass signal voltage (low-pass filters 306, 406 disclosed in paragraphs [0027]–[0028]).
Mulders et al. are not understood to explicitly disclose: use the high-pass signal voltage to determine the fault transients in the sum current at fault occurrence; and use the sharp edges of the high-pass signal voltage to synchronize a start time of travelling wave pulses, wherein the sharp edges are rapidly rising and/or rapidly falling edges of the high pass-signal voltage.
Kojovic et al. disclose that faults generate traveling wave currents that propagate through the system (paragraph [0018]); that traveling wave currents are high-frequency transient components superimposed on the fundamental frequency (paragraph [0042]); that Rogowski coils detect rapid current changes proportional to di/dt and are particularly sensitive to high-frequency components (paragraph [0037]); and that when the output signal exceeds a threshold value, a processor generates a standard amplitude and width tracking pulse used by timing logic to determine fault location (paragraph [0042]); further disclosing synchronization of traveling wave arrival times using reference timing (paragraph [0041]).
It would have been obvious to modify the apparatus of Mulders et al. to use the high-frequency component of the measured signal to determine fault transients and to use sharp rising or falling edges of the high-frequency signal to synchronize traveling wave timing, as taught by Kojovic et al., because Kojovic emphasizes that high-frequency transient detection and edge-based timing improve fault localization speed and accuracy in power systems (see Kojovic’s paragraphs [0036] & [0042]), thereby enhancing the fault detection capability of the Mulders apparatus.
Regarding claim 16, Mulders et al. disclose the apparatus according to claim 11 including phase current measurement coils 202A–202C and ground fault detection circuit 400 configured to measure a summation of phase currents (paragraphs [0023], [0025], [0036]); filtering measured signals using filtering circuitry including low-pass filters 306 and 406 to condition voltage signals for controller processing (paragraphs [0027]–[0028]).
Mulders et al. are not understood to explicitly disclose wherein the high-pass signal voltage is used to acquire information about partial discharges.
Kojovic et al. disclose the high-pass signal voltage is used to acquire information about partial discharges (see faults generate high-frequency traveling wave currents in paragraph [0018]; wherein Rogowski coils detect rapid current changes proportional to di/dt and are sensitive to high-frequency components, paragraph [0037]); and that high-frequency transients are superimposed on the fundamental frequency component of the current waveform, see paragraph [0042], [0046] further discloses that Rogowski coils operate over a wide frequency range and detect small current changes, including sustained arcing fault currents).
It would have been obvious to use the high-frequency component of the measured signal in Mulders to acquire information about partial discharge-related phenomena because Kojovic explicitly teaches that high-frequency current transients are indicative of fault events and are detectable using Rogowski coils over a wide frequency range (see Kojovic’s paragraphs [0037], [0046]), thereby enabling identification of fault-related discharge activity in a power system.
Regarding claim 17, Mulders et al. disclose the apparatus according to claim 11 including phase current measurement coils 202A–202C configured to detect phase currents (paragraph [0023]); and series connection of secondary coils to measure summed current (paragraph [0025]).
Mulders et al. are not understood to explicitly disclose wherein at least one of the three current transformers is a Rogowski coil.
Kojovic et al. disclose that at least one of the three current transformers is a Rogowski coil (see [0036], wherein a Rogowski coil is positioned around a transmission line conductor to detect traveling wave currents, Rogowski coils are particularly sensitive to high-frequency components and rapid current changes, paragraph [0037]; and that Rogowski coils operate over a wide frequency range and do not saturate, see paragraph [0046]).
It would have been obvious to substitute at least one of Mulders’ phase current measurement coils with a Rogowski coil because Kojovic teaches that Rogowski coils provide improved detection of high-frequency transients and fault currents in power systems (see Kojovic’s paragraphs [0037], [0046]), thereby improving transient detection performance.
Regarding claim 18, Mulders et al. & Kojovic et al. disclose the apparatus according to claim 11, wherein Mulders et al. further disclose controller 206 comprising communication interface 212 (paragraph [0030]); wherein processor 208, memory 210, and communication interface 212 is configured to communicate with other devices and networks and to retrieve and transmit data, see paragraph [0032]); and wherein the communication unit is configured to obtain data pertaining to the fault conditions from the calculation unit, and send such data to the remote device (see [0029]) & [0032] explicitly discloses that the communication interface 212 may include a transmitter, receiver, transceiver, or physical connection interface, and may be communicatively coupled with other external components; transmitting processed fault-related data from controller 206 to external devices through communication interface 212 corresponds to a communication unit coupled in communication with a remote device via a communication network, configured to obtain data pertaining to fault conditions from the calculation unit and send such data to the remote device).
Regarding claim 19, Mulders et al. & Kojovic et al. disclose the apparatus according to claim 18, wherein Mulders et al. further disclose upon receiving the data pertaining to the fault conditions, by the remote device, necessary actions are taken, by an electrical distribution grid operator and/or the fault management system, to rectify the fault (see the communication interface 212 configured to communicate with other devices and networks, [0032]; wherein processor 208 and controller 206 configured to process transmitted and received data (paragraph [0030]); and bidirectional data transfer capability via the communication interface (paragraph [0032]; the communication interface may retrieve data, transmit data, and be communicatively coupled with other devices, which inherently requires receipt of transmitted data by the remote device).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
U.S. 2021/0184449 A1 to Raisigel discloses a device for detecting an arc fault in a polyphase electrical installation comprises: a high-frequency measuring system coupled to at least two electrical phase lines of the installation, said measuring system being configured to extract a first signal representative of high-frequency components of electrical currents flowing through said phase lines; a plurality of low-frequency measuring systems, each coupled to one electrical phase line of the installation, each being configured to acquire a second signal representative of the alternating line current flowing through the corresponding phase line; and a data-processing module programmed to detect an arc fault on the basis of the second signals and of the first signal.
U.S. 2021/0088556 A1 to Bernal et al. disclose a circuit interrupter including a busbar, a Rogowski coil disposed around the busbar and structured to sense current having a first frequency flowing through the busbar, a test injector circuit structured to input a test signal having a second frequency to the Rogowski coil, high or band pass filter circuitry structured to receive an output of the Rogowski coil, the output including a first component having the first frequency and being proportional to the current through the busbar and a second component having the second frequency and being proportional to a temperature of the Rogowski coil, and to attenuate the first component of the Rogowski coil output, and an electronic trip unit including a temperature measurement unit structured to receive an output of the high or band pass filter circuitry and to estimate the temperature of the busbar based on the output of the high or band pass filter circuitry.
U.S. 2023/0006435 A1 to Melli et al. disclose devices herein may include conductor lines connected between a power supply and load, each of the conductor lines coupled to an AC contactor and a contactor control circuit, wherein the contactor control circuit is operable to open and close one or more contactors of the AC contactor. The devices may further include a current transformer coupled to the conductor lines, the current transformer operable to output a secondary current corresponding to a primary current magnitude of an electrical current not flowing to the load, wherein the AC contactor is connected between the power supply and the load. Devices may further include a zero cross detection circuit operable to generate an interrupt at each of a plurality of zero crossings for a microprocessor, and determine whether to open the one or more contactors of the AC contactor in a predetermined optimum interval calculated with respect to the zero crossing points.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to TRUNG NGUYEN whose telephone number is (571)272-1966. The examiner can normally be reached on Mon- Friday 8AM - 4:00PM Eastern Time. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Huy Phan can be reached on 571-272-7924. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of an application may be obtained from the Patent Application Information Retrieval (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAIR. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see http://pair-direct.uspto.gov. Should you have questions on access to the Private PAIR system, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative or access to the automated information system, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
Examiner: /Trung Q. Nguyen/- Art 2858
February 18, 2026
/RICHARD ISLA/Primary Patent Examiner, Art Unit 2858 February 20, 2026