Abstract: A directional fault location and isolation system for a three phase electric power circuit that identifies a faulted segment by determining the direction of the fault at multiple tap points in the electric power circuit. The directional fault controller, which may be a centralized controller or a number of peer-to-peer controllers located at the tap points, includes communication equipment for exchanging information with the monitoring equipment and the sectionalizing equipment at each sectionalizing control point, which includes the tap points and may also include the substations. The controller also includes processing equipment that determines the directionality of a fault on the power line at each current monitoring device, identifies a faulted line section by identifying a change in the directionality of the fault associated with the faulted line section, and operates one or more of the sectionalizing switches to isolate the faulted line section from the circuit.

Abstract: A directional fault sectionalizing system that utilizes one phase voltage measurement and three phase current measurements to determine the directionality of high impedance faults on a three phase electric power circuit. This eliminates the need for two of the three voltage measuring devices at each monitoring station conventionally required to determine fault directionality, which makes it economical to install at a greater number of distribution tap points. The system is particularly useful for commonly used three-way tap points along distribution lines where three phase voltage measurement is not readily available. The system is capable of identifying faults under challenging circumstances, such faults occurring on unbalanced three phase power lines and faults occurring on tapped line segments where the currents are relatively small compared to the currents flowing in the main line segments.

Abstract: A limited flash-over electric power switch uses a dielectric gas regulator and a flash-over arrestor to greatly diminish the occurrences of high voltage flash-over during operation of a circuit interrupter. The dielectric gas regulator prevents the flow of the dielectric gas into the arc gap during an initial portion of the opening stroke of the interrupter contacts. Once the arc gap is sufficiently wide to greatly diminish the likelihood of a high voltage flash-over, the dielectric gas regulator allows the dielectric gas to flow into the arc gap to extinguish the arc. The flash-over arrestor snubs out incipient flash-over that may occur as the arc attempts to reform across the arc gap. The flash-over arrestor may be a conductive ring located on the interior surface of the nozzle in the region of the orifice.

Abstract: A magnetic interrupter consisting of a stationary and moving butt contacts that open an electric circuit in dielectric gas (e.g., SF6) contained in a sealed, pressurized insulating housing. One or both of the contacts contain a magnet with poles spaced apart in a radial plane perpendicular to the axial direction to spin the arc in the radial plane about the center of the contacts. Permanent magnets may be used to spin the arc so that the magnetic field is not affected by the magnitude of the arcing current, which makes the magnetic interrupter suitable for interrupting currents below fault level currents. One or both of the magnets may also be a field coil and a permanent magnet may be used in combination with a field coil.

Abstract: A limited flash-over electric power switch uses a dielectric gas regulator and a flash-over arrestor to greatly diminish the occurrences of high voltage flash-over during operation of a circuit interrupter. The dielectric gas regulator prevents the flow of the dielectric gas into the arc gap during an initial portion of the opening stroke of the interrupter contacts. Once the arc gap is sufficiently wide to greatly diminish the likelihood of a high voltage flash-over, the dielectric gas regulator allows the dielectric gas to flow into the arc gap to extinguish the arc. The flash-over arrestor snubs out incipient flash-over that may occur as the arc attempts to reform across the arc gap. The flash-over arrestor may be a conductive ring located on the interior surface of the nozzle in the region of the orifice.

Abstract: A current monitoring device (CMD) with a set of electromagnetic field sensors located within one or more grounded housings positioned within the combined electromagnetic fields generated by one or more electric power lines. The CMD includes electronics, typically located within the grounded housings, defining impedance networks that combine the measurements received from the field sensors to create output signal indicative of electric current values for the phase conductors. The housings can be conveniently attached and to transmission line towers, distribution line poles, and high voltage power line supports in transmission and distribution substations. The CMD controls response equipment, such as a circuit interrupter that responds to current disturbances detected by the CMD. The CMD may also include communication for sending the current values to a remote controller, such as a central control station, that implements a wide range of response equipment.

Abstract: A current pause device configured to enhance the operation of transmission and distribution line circuit interrupters by delaying the voltage build across the circuit interrupter arc gap for a time period sufficient to allow the dielectric characteristic of the medium within the arc to recover. This allows the circuit interrupter to break the circuit at a lower arc gap voltage than would occur without the current pause device. The current pause device includes a conductive arcing horn and an insulator interposed in the arcing horn to create a conductive gap in the arcing horn and a voltage protection arrangement to limit the voltage across the current pause device and thereby prevent a voltage breakdown across the current pause device. Specifically, the voltage protection arrangement includes a diode connected to the arcing horn in parallel with the insulator and a dielectric spark gap device connected in parallel across the insulator.

Abstract: An electric power switch suitable for use as a capacitor switch that includes a drive unit having a bi-directional toggle mechanism and linearly opposing opening and closing spring latches. The opening and closing spring latches are located on opposing sides of the toggle mechanism, which includes an open-cage spring mechanism with coaxial, nested opening and closing springs operated by a rotating, motor-driven charging cam. To open the circuit interrupter, the opening spring latch is tripped to release the opening spring and thereby remove the capacitor bank from the electric power circuit. To introduce the capacitor bank into the electric power circuit, the motor rotates the charging cam through one complete rotation, which charges the opening and closing springs and trips the closing spring latch to release the closing spring to close the circuit interrupter and thereby introduce the capacitor bank into the electric power circuit.

Abstract: A current monitoring device (CMD) with a set of electromagnetic field sensors located within one or more grounded housings positioned within the combined electromagnetic fields generated by one or more electric power lines. The CMD includes electronics, typically located within the grounded housings, defining impedance networks that combine the measurements received from the field sensors to create output signal indicative of electric current values for the phase conductors. The housings can be conveniently attached and to transmission line towers, distribution line poles, and high voltage power line supports in transmission and distribution substations. The CMD controls response equipment, such as a circuit interrupter that responds to current disturbances detected by the CMD. The CMD may also include communication for sending the current values to a remote controller, such as a central control station, that implements a wide range of response equipment.

Abstract: An electric power monitoring and response system using electromagnetic field sensors located remotely beside the phase conductors. The system determines unknown system variables for one or more three-phase power lines based on measured values obtained form the field sensors and, in some cases, known power system values. For a given physical configuration, the field sensors may include a magnetic or electric field sensors, and the known system values as well as the unknown system variables may include phase currents, phase voltages and distances defining the physical configuration of the system. The response equipment may be a display, a circuit interrupting device, a voltage regulator, a voltage sag supporter, a capacitor bank, communication equipment, and reporting system.

Abstract: An electric power interrupter with an internal contactor that is suitable for use as a line and load switch constructed from light weight materials including a fiberglass or composite insulator and aluminum flanges. The light weight design feature allows the power interrupter to be supported above a standard disconnect switch insulator without having to replace or reinforce the insulator. The power interrupter also includes a latch mechanism with a low-force trip action, such as a spring-driven toggle mechanism that accelerates the internal contactor to break the electric power circuit on the opening stroke. This low-force trip action allows the power interrupter to be actuated by a standard disconnect switch operating mechanism without having to upgrade or augment the standard operating mechanism. For these reasons, the power interrupter may be installed as a retrofit upgrade to an existing standard disconnect switch without having to modify the underlying disconnect switch.

Abstract: A capacitor switch including a power contactor and an impedance contactor located within a relatively slender container filled with dielectric gas. The container may be a “dead tank” or an insulator. For the insulator configuration, the switch also includes a conductive cap housing a charging impedance located on the end of the insulator. The power contactor includes a relatively fixed probe contact and a linearly moving socket. The impedance contactor is ring-type butt contactor surrounding the penetrating contactor that includes a retracting (but otherwise fixed) contact that surrounds the fixed probe, and a traveling ring contact that surrounds and moves with the moving socket contact. The impedance contactor closes before the power contactor on the closing stroke to introduce the charging impedance into the circuit. A puffer mechanism retards the expansion of the retracting contact on the opening stroke, which causes the impedance contactor to open before the power contactor.

Abstract: A voltage sag and over-voltage compensation device for an AC electric power distribution system employing cascaded switching devices and a pulse-width modulated transformer. Each stage of the cascaded switching device includes a switching element located within a full-bridge rectifier circuit to allow bi-directional switching through each switching element (i.e., switching through the same switching element during the positive and negative portions of the AC voltage cycle). Each full-bridge rectifier also includes a snubber circuit connected in parallel with a corresponding switching element to absorb the current discharge caused by switching the input power supply to the transformer through the corresponding switching device under non-zero current conditions.

Abstract: An interrupter switch mechanism 18, an actuator mechanism 20 for operating the switch mechanism 18, an engagement arm 30 such as a whip, a first resistor 22, a second resistor 26, a drive mechanism 64 for pivoting the engagement arm 30 into contact with the resistors 22 and 26, and a drive shaft 62. The drive mechanism 64 has a first hub 82, a second hub 84 that is biased relative to the first hub 82, and a pivotal latch member 66 that is biased towards an engaged position with the second hub 94. The drive shaft 62 sequentially operates the drive mechanism 64 to introduce the first resistor 22 and then the second resistor 26, and then operates the actuator 20 to close the switch mechanism 18, for reducing electrical disturbances when switching a capacitor bank 12 into an electric power circuit 16.

Abstract: An actuator mechanism that decreases the time needed to move the contacts of a circuit interrupter between a closed circuit position and an open circuit position to reduce the probability of the occurrence of restrikes. The actuator mechanism uses a toggle spring arrangement that uses a single spring to move the interrupter through both an opening stroke and a closing stroke. The interrupter is designed to connect to the circuit in parallel, so that the interrupter is not normally in the circuit when the circuit is closed. Because the interrupter is not normally in the circuit, it can be manufactured to less stringent standards than those that apply to electrical components that normally remain in the circuit. The interrupter is well adapted for use as a puffer-type interrupter in which the contacts of the interrupter are contained in an arc-extinguishing gas, such as sulphur-hexaflouride (SF6) gas to further reduce the probability of restrikes and to minimize the effect of occurring restrikes.

Abstract: A voltage sag and over-voltage compensation device for an AC electric power distribution system employing cascaded switching devices and a pulse-width modulated transformer. Each stage of the cascaded switching device includes a switching element located within a full-bridge rectifier circuit to allow bi-directional switching through each switching element (i.e., switching through the same switching element during the positive and negative portions of the AC voltage cycle). Each full-bridge rectifier also includes a snubber circuit connected in parallel with a corresponding switching element to absorb the current discharge caused by switching the input power supply to the transformer through the corresponding switching device under non-zero current conditions.