University of Connecticut

Instrument Manufacturing Company

Energy Development Associates

Other

Matthew S Mashikian

Andrzej Pawel Szatkowski

Robert B Northrop

Rajeev Bansal

Joseph H Groeger

Bruce S Bernstein

Curtis C Whittlesey

Francesco Palmieri

Dong Sui

Paul S Mashikian

Zhifang Du

John A Tanaka

Chrysostomos L Nikias

Robert B Northop

Exemplary embodiments of the present disclosure are directed to resonant transformers (or reactors) and coil arrangements associated with resonant transformers. The coil arrangements can include a grounding coil configured to generate a net-zero induced voltage between a first end of the grounding coil and a second end of the grounding coil layer, and one or more step-up coil layers formed by one or more layers of pressure tape, insulating materials, and wire wrapped to form coils about a portions of a split magnetic core. The split magnetic core can include a first core segment and a second core segment, where one of the core segments is disposed within a main housing and one of the core segments is disposed external to the main housing. A gap between the first and second core segments can be manipulated to control an inductance of the resonant transformer.

Resonant Transformer

A resonant test system can be configured to adjust an inductance to set the inductance of the resonant test system to a test inductance value and to adjust an output frequency of the resonant test system to set the output frequency to a test output frequency. The inductance of the resonant test system can be adjusted by controlling a reactor of the resonant test system and the output frequency of the resonant test system can be controlled by an inverter of the resonant test system. The test inductance value and the test output frequency the test inductance value and the test output frequency can be automatically and dynamically set by a controller of the resonant test system to achieve resonance in series with an electrical power cable under test. One or more diagnostic tests can be performed on the electrical power cable.

Electrical cable diagnostic system

Resonant transformer

The present disclosure is directed to cable diagnostic test methods, systems and apparatus that advantageously utilize 'standing wave'principles to facilitate the identification and location of defect(s) along a power cable. The disclosed methods/systems are effective in measuring dissipation factors and dielectric constants associated with shielded power cable insulation at any number of points or sections along the axial length of the cable. In essence, the disclosed methods/systems perform what may be termed axial tomography, allowing the dielectric loss or dissipation factor and the dielectric constant of the insulation as well as the resistance and inductance of the cable conductor system to be determined at one or more pre-determined points/sections of the cable along its axis.

Diagnostic methods for electrical cables utilizing axial tomography

An improved jacket material for insulated electric cable wherein the jacket contains one or more additives of an ion exchange resin and/or an ionic scavenging compound for neutralizing or capturing ionic impurities.

Jacket for insulated electric cable

A method and apparatus for detecting the location of an incipient fault in an insulated power which includes the application of an excitation voltage to a power line to produce a partial discharge signal pulse at a fault along the power line. The surface of the power line is scanned with two axially spaced sensors disposed adjacent the surface of the power line, the sensors detecting the partial discharge signal pulse to produce discrete detected pulses. These detected pulses are combined to produce a combined signal having all amplitude level which reaches an extreme value when the fault is located equidistantly between the sensors. The sensors are moved along the power line until the fault is located substantially equidistantly between the sensors as indicated by the extreme amplitude level of the combined signal.

Cable partial discharge location pointer

Test apparatus for a high voltage cable installation includes a high AC voltage source having the frequency range intended to be carried by the cable installation and a high DC voltage source. A switch alternately passes positive and negative polarities of the DC voltage, and the AC voltage source and the alternating polarity DC voltage output from the switch are coupled while isolating the voltage sources from each other. The resulting alternating polarity DC-biased AC voltage is injected into the cable installation to produce indications of incipient faults.

Cable fault detection using a high voltage alternating polarity DC

A method and apparatus for locating an incipient fault at a point along the length of an insulated power line includes the application of an excitation voltage at an open end of the power line, and the signal pulse transmitted along the power line to the open end is passed through a high pass filter to remove the portion of the signal which is at a frequency below the excitation voltage and its harmonics. The filtered signal is amplified and passed through a band pass filter to remove a high frequency portion of the signal containing a large proportion of noise relative to the frequency of the partial discharge frequency from the incipient fault. This filtered signal is passed to a digital storage device adapted to be triggered by a signal of a predetermined amplitude, and the triggered digital storage device receives the amplified signal directly from the amplifier and stores digital data concerning amplitude and time for the peaks of the amplified signal for a predetermined period of time. The stored digital data is processed to identify the peaks reflecting the point of partial discharge in the power line.

Method and apparatus for the detection and location of faults and

An electric protective device for protecting a cable, its termination or other apparatus from the effect of lightning strikes on an overhead line to which the apparatus is connected comprises a tubular insulator combined with a surge arrester and integrated by common terminals at the ground and high voltage ends. The insulator and the surge arrester are concentrically disposed about the conductor in a common insulated structure to eliminate connecting leads therebetween and the voltage drop which occurs across such leads during a rapid rise in current. The surge arrester may contribute all or part of the electrical stress grading required in the termination.

Electrical protective device

A method and apparatus of detecting the locations of incipient faults in an insulated power line which comprises the method steps of opening one end of the power line, if it is not suitably terminated to reflect high frequency pulses, applying an excitation voltage to the other end of the power line at an excitation point, detecting a first high frequency pulse produced by a discharge in the power line and transmitted on the power line to the excitation point, detecting a first reflection of the pulse from the open end of the power line to the point of excitation, detecting the travel time of a reflection of the first pulse from the excitation point to the open end of the power line and return to the excitation point, and dividing the time between the detection of the first pulse and the first reflected pulse by the detected travel time. The invention also provides a method and means for only detecting discharge pulses which occur in a predetermined range of magnitude of the excitation voltage and discharge pulses which reside within predetermined ranges of magnitudes. The discharge sites may be detected using either reflected voltage or current pulses.

Method and instrumentation for the detection, location and

A battery plant is described which features magnetic circuit means in association with each of the battery strings in the battery plant for balancing the electrical current flow through the battery strings by equalizing the voltage across each of the battery strings. Each of the magnetic circuit means generally comprises means for sensing the electrical current flow through one of the battery strings, and a saturable reactor having a main winding connected electrically in series with the battery string, a bias winding connected to a source of alternating current and a control winding connected to a variable source of direct current controlled by the sensing means. Each of the battery strings is formed by a plurality of batteries connected electrically in series, and these battery strings are connected electrically in parallel across common bus conductors.

Device for balancing parallel strings

A zinc-chlorine battery plant system and method of redirecting the electrical current around a failed battery module. The battery plant includes a power conditioning unit, a plurality of battery modules connected electrically in series to form battery strings, a plurality of battery strings electrically connected in parallel to the power conditioning unit, and a bypass switch for each battery module in the battery plant. The bypass switch includes a normally open main contact across the power terminals of the battery module, and a set of normally closed auxiliary contacts for controlling the supply of reactants electrochemically transformed in the cells of the battery module. Upon the determination of a failure condition, the bypass switch for the failed battery module is energized to close the main contact and open the auxiliary contacts. Within a short time, the electrical current through the battery module will substantially decrease due to the cutoff of the supply of reactants, and the electrical current flow through the battery string will be redirected through the main contact of the bypass switch.

Growing community of inventors

Storrs, CT, United States of America

Matthew S Mashikian