Abstract:
In the examples provided herein, an apparatus has a memristive element coupled to a pin of an integrated circuit, wherein the memristive element switches from a first resistance within a first range of resistance values to a second resistance within a second range of resistance values in response to an electrostatic discharge (ESD) event at the pin. The apparatus also has read circuitry coupled to the memristive element to determine whether a resistance of the memristive element is in the first or second range of resistance values, wherein the read circuitry includes a first transistor. Further, the coupling between the read circuitry and the memristive element does not include a direct path for current from the ESD event to a gate terminal of the first transistor.
Abstract:
A portable switching device to remotely operate a high voltage circuit breaker, the portabele switching device is locally temporarily electrically connected to the controling ciruit of the high voltage circuit breaker and comprises: a voltage input (206); a voltage output (208, 210) for connecting to the external circuit; a ground input (212); an overvoltage protection circuit (201) connected between the voltage input (206) and the ground input (212); and a switching unit (203, 205) comprising a first switching circuit having an input connected to the voltage input and an output connected to the voltage output, the first switching circuit comprising a relay (2032), a relay contact protection circuit (2034), and an overload protection circuit (2036); wherein the first switching circuit is remotely controllable to switch the external circuit from a first operating state to a second operating state.
Abstract:
The invention relates to the field of a security framework for transmitting communication messages between a Substation LAN and packet-switched WAN, in particular, a network interface for transmitting protection data in a power network. The present invention provides a network interface for transmitting communication data including protection data of a power communication network, between a Substation Ethernet LAN and a packet-switched WAN usually in Layer 2. The network interface comprises: a firewall and a Layer 3 router being connected with each other and adapted to transmit the communication data excluding the protection data; and a Layer 2 bypass being in parallel with the firewall and the Layer 3 router, and adapted to transmit the protection data. According to a further aspect, the present invention also provides a method for transmitting such communication data.
Abstract:
A low fault current isolation arrangement senses loss of voltage and automatically isolates and de-energizes a down live primary wire if overcurrent protection devices have not cleared the high impedance fault in an electric power distribution network. Incorporating an operator selectable time delay response, the low fault current isolation arrangement permits overcurrent protection devices to attempt to detect and shut down the affected conductor, and isolates and shuts down the low current fault if the overcurrent devices are not successful. The isolation arrangement continuously monitors AC voltage as remotely provided by smart meters even after a fault location is de-energized, and serves as a back up, and not as a replacement, for existing overcurrent protection schemes. A host computer operates in conjunction with plural smart meters each coupled to an associated customer distribution transformer in conjunction with the fault isolator to detect and shut down high impedance faults.
Abstract:
A circuit breaker (2;2';2") for an electric load (4) includes first (12,14,16,26) and second (18,20) terminals; a number of first separable contacts (48;48') each electrically connected between one of the first terminals and one of the second terminals; a first mechanism (50) to open, close or trip open the first contacts; a number of second separable contacts (24;24') each electrically connected in series with a corresponding one of the first contacts; a second mechanism (44) to open or close the second contacts; a processor (68) to cause (200) the second mechanism to open or close the second contacts, annunciate through one of the second terminals a power circuit electrical parameter for the electric load, receive from a number of the second terminals a confirmation from or on behalf of the electric load to cause the second mechanism to close the second contacts, and determine (500) a fault state operatively associated with current flowing through the second contacts.
Abstract:
The present application discloses detecting manipulation of GNSS signals using a second time source. If two or more GNSS constellation signals are being detected, the phase error between the GNSS constellation signals may be monitored. When the phase error drifts, then manipulation is determined. The integrity of a GNSS constellation signal may be monitored using an internal time source such as a crystal oscillator by monitoring a slope of the free running counter at the detected rising edges of a pulse-per-second signal from the GNSS constellation. If more than two GNSS constellations are monitored, a voting scheme may be used to determine the manipulated GNSS constellation.