Eric A Udren, 771395 Terrace Dr, Pittsburgh, PA 15228

2003022, Dec 4, 2003

Dec 22, 2000

09/747345

Eric Udren - Pittsburgh PA, US

H02H003/00

361/065000

A distributed bus differential relay system has a separate differential relay element at each feeder location to trip the associated circuit breaker in response to a fault in the protected bus. The only conductors between feeders form a set of leads connecting current transformers in each of the feeders in parallel. Preferably, the current transformer in each feeder also serves as the current transformer for the associated circuit breaker and the differential relay element is incorporated into the overcurrent relay or trip unit of the circuit breaker which is implemented by a microprocessor. Compliance voltage across the cts is limited by a varistor or saturating reactor which is protected from overheating by a time delayed shorting device.

2014002, Jan 30, 2014

Jul 26, 2013

13/952433

Eric A. Udren - Pittsburgh PA, US

SAN DIEGO GAS & ELECTRIC COMPANY - San Diego CA

H02H 3/02

307130, 307125, 307131

Methods and systems for detecting a falling power line in a power transmission or distribution system are described. Electrical measurements at various points in the power distribution system are used to detect changes in a power line indicating that the conductor has broken or become disconnected. Upon detection, control mechanisms are used to deenergize the conductor while the conductor is falling and/or before it contacts the ground.

4402028, Aug 30, 1983

Aug 17, 1981

6/293531

Eric A. Udren - Monroeville PA

Electric Power Research Institute, Inc. - Palo Alto CA

H02H 7045

361 36

Differential protective relay methods and apparatus which include a differential current function supervised by both a harmonic restraint function and a voltage change function. The voltage change function determines whether or not the differential current function requires harmonic restraint supervision, preempting such supervision when it is not required, to enable faster trip decisions to be made by the differential current function.

4305108, Dec 8, 1981

Sep 21, 1979

6/077877

Eric A. Udren - Monroeville PA

Westinghouse Electric Corp. - Pittsburgh PA

H02H 3093

361 96

A polyphase time overcurrent detector provides a variably delayed control signal wherein the delay is inversely related to both the current magnitude and the number of faulted phases. Current transducers produce input signals representative of the current flowing in each phase of the polyphase system. The input signals are added together to produce a charging signal. If at the end of a predetermined time period the fault has not been cleared, the charging signal will begin to charge a capacitor. If the capacitor charges to a predetermined voltage level within a fixed time period, the control signal is initiated.

4475209, Oct 2, 1984

Apr 23, 1982

6/371090

Eric A. Udren - Monroeville PA

Westinghouse Electric Corp. - Pittsburgh PA

H04B 356

375 4

A regenerator for providing detection, remodulation, and retransmission of a digital data signal propagated in the differential mode over a pair of bundle conductors of a power line. The electric power signal, propagated in the common mode over the same bundle conductors, is conducted through the regenerator and provides a power supply voltage for the regenerator electronics. A series of electrical traps prevent the electric power signal from being conducted into that portion of the regenerator utilized for processing of the data signal. The regenerator also includes bypass switches for by-passing the regenerator electronics when a power supply voltage sufficient to operate the electronics is unavailable.

4471399, Sep 11, 1984

Mar 11, 1982

6/357239

Eric A. Udren - Monroeville PA

Westinghouse Electric Corp. - Pittsburgh PA

H04B 160
H02H 726
H04M 1104

361 64

A communication system for transmitting baseband digital signals on an electrical power line. A pulse generator produces digital signals which are limited to a frequency spectrum of 30 kHz to 300 kHz and applied directly, i. e. , without modulation, to an electrical power line. At the receiving terminal an amplifier compensates for attenuation characteristics of the electrical power line and the received signal is then sampled to extract the information from it. To avoid interference when both a transmitting and receiving link are located at a substation, the baseband system incorporates a mimic network to mimic the interference signal erroneously picked up by the receiving link from the transmitting link located at the same substation. The mimic signal is then subtracted from the interference signal to neutralize the effect of the latter. When both a baseband digital communication system and a carrier communication system utilize the same electrical power lines, provision is made for interrupting the baseband digital signal to allow communications via the carrier system.

4862308, Aug 29, 1989

May 1, 1987

7/044647

Eric A. Udren - Coral Springs FL

Electric Power Research Institute, Inc. - Palo Alto CA

H07H 308

361 45

A power bus fault detector for detecting faults in a predefined portion of an electrical power bus having at least one phase. Power feed lines are coupled to the predefined portion of the power bus by circuit breakers. Current transformers are used to detect the current flowing through each phase of each power feed line which is coupled to the predefined portion of the power bus. A summer generates a current differential signal for each phase that is equal to the sum of the currents detected by the current transformers. A fault detector generates a trip signal which causes the feed line circuit breakers to disconnect the feed lines from the power bus when a fault is detected in the predefined portion of the power bus. The fault detector includes a detector which detects when the current differential signal in any of the power bus's phases is substantially nonsinusoidal in shape. In a preferred embodiment, the fault detector detects when, for any of the phases, the percentage of time that the magnitude of the current differential signal exceeds a fault cutoff value is greater than the percentage of time that the current differential value exceeds the fault cutoff value for a known minimum fault.

4528611, Jul 9, 1985

Feb 22, 1983

6/468742

Eric A. Udren - Monroeville PA

Westinghouse Electric Corp. - Pittsburgh PA

H02H 318

361 81

New logic circuitry for a directional comparison blocking protective relay scheme. A forward-reaching and a reverse-reaching protective relay located at the local and remote terminals of a protected line segment determine whether a fault is internal or external to the protected line segment. To carry out this function, the protective relays produce signals representative of fault location and communicate with each other via a communications channel. A fault detector and logic circuitry is provided at each terminal for processing the produced signals to determine the fault location and avoid tripping when the fault character changes. By using fault detectors to determine the existence of a fault, the logic at each terminal for combining the signals is simplified and security against false tripping is improved.