Abstract: A high voltage electric switch includes contacts with graphite carbon electrode forming the arc gap. In addition, the carbon contacts are located in a chamber containing at least 60% carbon dioxide (CO2) as a dielectric gas to achieve improved arc interrupting performance. In conventional switches, the metallic contacts introduce metallic vapors into the arc plasma that inhibits the ability of the dielectric gas to interrupt high voltage, high current arcs. As the element carbon is inherently present in CO2 gas, the addition of vapors from the carbon electrodes into the dielectric gas does not significantly interfere with the dielectric arc-interrupting performance of the CO2 dielectric gas.

Abstract: A calibration joint for a three-phase electric disconnect switch includes a linkage pipe extending through a lock ring, which includes an axial guide shaft, a threaded shaft, and a self-piercing set screw securing the lock ring to the linkage pipe. The linkage pipe also extends through a clevis housing, which includes an axial joiner shaft and a clevis bracket securing the clevis housing to an operating lever of the disconnect switch. An adjustment rod extending through the axial guide shaft of the lock ring, through the axial joiner shaft of the clevis housing, and engaging with lock nuts allows axial adjustment of the clevis housing with respect to the lock ring, and thus with respect to the linkage pipe. This, in turn, allows fine adjustment of the blade and jaws of an associated phase switch with respect to the switch actuator independent of the other phase switches.

Abstract: A quick-set clevis joint for a three-phase electric disconnect switch linkage includes a clevis housing having a spring chamber axially aligned and disposed around a linkage pipe extending through the clevis housing. A spring positioned within the spring chamber provides play in the linkage. First and second thrust disks compress the spring in a first axial direction with the first thrust disk pushed against a first spring chamber end wall when the linkage pipe moves in the first axial direction while the clevis housing is blocked from moving in the first axial direction. In addition. the first and second thrust disks compress the spring in the second axial direction with the second thrust disk pushed against the second spring chamber end wall when the linkage pipe moves in the second axial direction while the clevis housing is blocked from moving in the second axial direction.

Abstract: A time-admittance fault detection and isolation system includes a series of time-admittance switches spaced apart along the power line, each including a respective time-admittance function. Together, the time-admittance functions define a cascade trip sequence in a downstream-to-upstream direction, which autonomously causes a closest upstream time-admittance switch to a fault to trip to isolate the fault on an upstream side of the fault without communication with the time-admittance switches. The fault detection and isolation system may also include a radio communicating a trip signal from the closest upstream time-admittance switch to the fault to a closest downstream time-admittance switch to the fault. The trip signal causes the closest downstream time-admittance switch to the fault to trip to isolate the fault on a downstream side of the fault. A tie switch closes to back-feed a portion of the electric power line downstream from the closest downstream time-admittance switch to the fault.

Abstract: A smart switch allows distributed generators to “ride through” non-three-phase faults by very quickly detecting a non-three-phase phase fault, locating the fault, identifying the “responsive sectionalizer switches” that will be involved in clearing or isolating the fault, and selecting one of the responsive sectionalizer switches to direct back-feed tie switch operations. The responsive sectionalizer switches trip only the faulted phase(s), and the selected sectionalizer switch instructs a back-feed tie switch to close to back-feed the distributed generators prior to conducting the typical fault response operation. This typically occurs within about three cycles, and is completed before the normal fault clearing and isolation procedures, which momentarily disconnect all three phases to the distributed generators from the normally connected feeder breaker.

Abstract: An instrumented electric power voltage arrester includes a temperature sensor, wireless transmitter, and a visual over-temperature indicator. A disk shaped module, a replacement varister block, or a dummy block containing the sensor/transmitter is placed between varister blocks inside the arrester housing. A strap-on module is attached to the outside of the arrester housing. The sensor/transmitter utilizes a harvesting power supply that draws electric power for the electronics from the power line protected by the arrester. An ambient temperature sensor may be utilized to enhance accuracy. The temperature sensor/transmitter typically sends arrester monitoring data wirelessly to an RTU or handheld unit located outside the arrester, which relays the monitoring data to an operations control center that scheduled replacement of the arrester based on the monitoring data. A surge counter keeps track of the number of equipment and lightning related temperature surges experienced by the arrester.

Abstract: A high voltage electric switch includes contacts with graphite carbon electrode forming the arc gap. In addition, the carbon contacts are located in a chamber containing at least 60% carbon dioxide (CO2) as a dielectric gas to achieve improved arc interrupting performance. In conventional switches, the metallic contacts introduce metallic vapors into the arc plasma that inhibits the ability of the dielectric gas to interrupt high voltage, high current arcs. As the element carbon is inherently present in CO2 gas, the addition of vapors from the carbon electrodes into the dielectric gas does not significantly interfere with the dielectric arc-interrupting performance of the CO2 dielectric gas.

Abstract: A fault-preventing circuit recloser includes a ballast impedance, power line current and voltage monitors, and controller that operates the switch based on measurements obtained from the current and voltage monitors. The controller aborts the closing (i.e., reopens the switch) when the controller detects that the switch has closed into faulted line. The circuit recloser temporarily introduces the ballast impedance into the circuit during the closing operation to limit the current spike and voltage dip caused by initially closing the switch into the faulted line. The circuit recloser also temporarily introduces the ballast impedance into the circuit during the opening operation to limit the voltage transient that can be caused by initially opening a load-carrying power line. Different ballast resistor insertion times are applied depending on the type of recloser operation (opening or closing) and whether a fault is detected.

Abstract: An instrumented electric power voltage arrester includes a temperature sensor, wireless transmitter, and a visual over-temperature indicator. A disk shaped module, a replacement varister block, or a dummy block containing the sensor/transmitter is placed between varister blocks inside the arrester housing. A strap-on module is attached to the outside of the arrester housing. The sensor/transmitter utilizes a harvesting power supply that draws electric power for the electronics from the power line protected by the arrester. An ambient temperature sensor may be utilized to enhance accuracy. The temperature sensor/transmitter typically sends arrester monitoring data wirelessly to an RTU or handheld unit located outside the arrester, which relays the monitoring data to an operations control center that scheduled replacement of the arrester based on the monitoring data. A surge counter keeps track of the number of equipment and lightning related temperature surges experienced by the arrester.

Abstract: Fault detection, isolation and restoration systems for electric power systems using “smart switch” points that autonomously coordinate operations to minimize the number of customers affected by outages and their durations, without relying on communications with a central controller or between the smart switch points. Each smart recloser can be individually programmed to operate as a tie-switch, a Type-A (normal or default type) sectionalizer, or a Type-B (special type) sectionalizer. The Type-A recloser automatically opens when it detects a fault, uses a direction-to-fault and zone-based distance-to-fault operating protocol, and stays “as is” with no automatic opening when power (voltage) is lost on both sides of the switch. The Type-B sectionalizer does the same thing and is further configured to automatically open when it detects that it is deenergized on both sides for a pre-defined time period, and to operate like a tie-switch once open.

Abstract: A high voltage capacitor includes multiple capacitor packs housed in a canister. A capacitor pack status monitor includes a current sensor measuring an electric current through an associated capacitor pack and a radio transmitting a first signal representative of the electric current through a selected capacitor pack. The monitor also includes a voltage sensor measuring an electric voltage across the associated capacitor pack and a radio transmitting a second signal representative of the electric voltage across the selected capacitor pack. Electronics compute an impedance associated with each capacitor pack. Each current sensor may include a current transformer positioned around a main power line energizing a respective capacitor pack.

Abstract: Electric power Fault detection, isolation and restoration (FDIR) systems using “smart switches” that autonomously coordinate operations to minimize the number of customers affected by outages and their durations, without relying on communications with a central controller or between the smart switch points. The smart switches typically operate during the substation breaker reclose cycles while the substation breakers are open, which enables the substation breakers to reclose successfully to restore service within their normal reclosing cycles. Alternatively, the smart switch may be timed to operate before the substation breakers trip to effectively remove the substation breakers from the fault isolation process. Both approaches allow the FDIR system to be installed with minimal reconfiguration of the substation protection scheme.

Abstract: A high voltage electric power switch with an anti-flashover nozzle that suppresses the likelihood of a flashover occurring between switch components other than the switch contactors, such as the nozzle casing around the first contactor (e.g., female or socket) and the casing around the second contactor (e.g., male or pin) during an opening stroke of the contactors. The anti-flashover features include a corona ring positioned at the proximal end of the nozzle casing and a nozzle clamp ring positioned to the distal side of a nozzle casing abutment that mates with a nozzle receiver. The conventional nozzle includes a nib-shaped proximal end of the nozzle casing carrying a clamp ring positioned on the proximal side of the abutment. The new nozzle design reduces the high level of electric field stress created by the conventional nozzle casing to suppress the likelihood of a flashover occurring between the contactor casings.

Abstract: The present invention may be embodied in an in-line high voltage electric power line monitor including a DC current sensor, an AC current sensor, an energy harvesting power supply, and a communication device. The in-line power line monitor includes a bus bar that connects in series with the monitored power line. For example, the in-line power line monitor may be connected at the junction point between the monitored power line and a support structure, such a sectionalizing switch that supports the monitor positioned between the switch and the power line. A pair of DC current measurement pickups are spaced apart on the bus bar and operatively connected to the microprocessor. The in-line power line monitor also includes an AC current sensor coil and an energy harvesting device (e.g., inductive coil) that surround the bus bar. The AC current sensor coil and the power supply coil are positioned adjacent to, but spaced apart from, the bus bar.

Abstract: A remote blade closing detector switch is positioned on or near the jaws of an electric power disconnect switch, where proper seating of the blade in the jaws activates a detector switch. An extended conductor lead electrically connects the detector switch an RFID tag placed in a convenient reading location. The detector switch is configured to control a data signal, power to the antenna of the RFID tag, the power supply to the RFID tag, or a data signal between an RFID chip and an antenna as mechanisms for enabling and disabling the tag to report a status indicator. An antenna tuning compensator may be utilized to compensate for the impedance of the long conductor lead connected to the antenna. A noise filter may also be used to suppress electrical noise picked up by the long conductor lead in the harsh electrical environment of the disconnect switch.

Abstract: The present invention may be embodied in an in-line high voltage electric power line monitor including a DC current sensor, an AC current sensor, a voltage sensor, an energy harvesting power supply, and a communication device configured. The in-line power line monitor includes a bus bar that connects in series with the monitored power line. For example, the in-line power line monitor may be connected at the junction point between the monitored power line and a support structure, such a sectionalizing switch that supports the monitor positioned between the switch and the power line. A pair of DC current measurement pickups are spaced apart on the bus bar and operatively connected to the microprocessor. The in-line power line monitor also includes an AC current sensor coil and an energy harvesting device (e.g., inductive coil) that surround the bus bar. The AC current sensor coil, the power supply coil and the voltage sensor positioned adjacent to, but spaced apart from, the bus bar.

Abstract: A high voltage capacitor includes multiple capacitor packs housed in a canister. A capacitor pack status monitor includes a current sensor measuring an electric current through an associated capacitor pack and a radio transmitting a first signal representative of the electric current through a selected capacitor pack. The monitor also includes a voltage sensor measuring an electric voltage across the associated capacitor pack and a radio transmitting a second signal representative of the electric voltage across the selected capacitor pack. Electronics compute an impedance associated with each capacitor pack. Each current sensor may include a current transformer positioned around a main power line energizing a respective capacitor pack.