The invention relates to a self-adaptive positive-sequence current quick-break protection method for a petal-shaped power distribution network trunk line. The method comprises the following steps: step 1, calculating a positive-sequence voltage phasor and a positive-sequence current amplitude at a protection installation position when a fault occurs, acquiring and storing a positive sequence impedance value of a protected line; judging a fault type, and judging a fault direction; step 2, when a fault direction element judges that a fault occurs in the forward direction, selecting a self-adaptive current quick-break protection setting formula according to the fault type, and when positive sequence current measured by protection is larger than a protection setting value, judging that the protected line has a short-circuit fault, and making a circuit breaker trip quickly. Compared with the prior art, the method provided by the invention has enough sensitivity and does not change along with the change of the line length and the system operation mode.

Wireless communication enabled circuit breakers are described. Methods associated with such wireless communication enabled circuit breakers are also described. The wireless communication enabled circuit breakers may controlled by a remote entity. The remote entity may wirelessly case the wireless communication enabled circuit breakers to trip.

A personal electronic device can include a main printed circuit board having disposed thereon a processing unit, one or more auxiliary circuits coupled to the main printed circuit board by one or more corresponding flexible printed circuits and one or more temperature sensors disposed on one of the flexible printed circuits. A processing unit of the portable electronic device can be configured to monitor the one or more temperature sensors, provide a warning in response to a monitored temperature exceeding a first threshold, and to cause a shutdown of at least a portion of the personal electronic device in response to the monitored temperature exceeding a second threshold. The temperature sensors can be negative temperature coefficient resistors.

Systems, devices, and methods include protective functions in an electrical power system. For example, a processing subsystem may include a first processor and a second processor. The first processor and the second processor may operate independently. A memory subsystem may comprise a first memory section and a second memory section. A memory management subsystem may enable memory access between the first processor and the first memory section and disable memory access between the first processor and the second memory section. The memory management subsystem may further enable memory access between the second processor and the second memory section and disable memory access between the second processor and the first memory section. A protection subsystem may include the first processor and the first memory section and enable a protection function. The second processor and the second memory section may provide a second function that operates independently of the protection function.

A circuit may include an electronic switch that has a load current path coupled between an output node and a supply node and that is configured to connect or disconnect the output node and the supply node in accordance with a drive signal. Further, the circuit includes a monitoring circuit that is configured to receive a current sense signal, which represents the load current passing through the load current path, and that is further configured to determine a protection signal based on the current sense signal, a state of the monitoring circuit, and at least one wire parameter. The wire parameter characterizes a wire that is—during operation—connected to the output node, and the protection signal is indicative of whether to disconnect the output node from supply node. Further, the circuit includes a protection circuit connected to the monitoring circuit.

A method for analyzing power quality events in an electrical system includes processing electrical measurement data from or derived from energy-related signals captured by at least one of a plurality of metering devices in the electrical system to generate or update a plurality of dynamic tolerance curves. Each of the plurality of dynamic tolerance curves characterizes a response characteristic of the electrical system at a respective metering point of a plurality of metering points in the electrical system. Power quality data from the plurality of dynamic tolerance curves is selectively aggregated to analyze power quality events in the electrical system.

Systems and techniques are disclosed that monitor an area adjacent to power system components and detect objects that may pose a probable risk of causing a fault, for example, making contact with the power system component. Various embodiments initiate a preventative, a corrective, and/or a mitigative action in advance of the fault. Examples of possible actions include, but are not limited to, an audible alert, a visual alert, a tactile alert, a remote notification, a limiting of machinery motion, a stopping of machinery motion, a reversing of machinery motion, de-energization of the power system component, or combinations thereof.

A circuit breaker includes a solid-state switch, a sense resistor, a current detection circuit, and a switch control circuit. The solid-state switch and sense resistor are connected in series in an electrical path between a line input terminal and a load output terminal of the circuit breaker. The current detection circuit is configured to (i) sample a sense voltage that is generated across the sense resistor in response to load current flowing through the sense resistor, (ii) detect an over-current fault condition based on the sampled sense voltage, and (iii) output a fault detection signal in response to detecting the over-current fault condition. The switch control circuit is configured to control the solid-state switch, wherein the switch control circuit is configured to switch off the solid-state switch in response to the fault detection signal output from the current detection circuit.

The present disclosure relates to a method for controlling a distance protection system, as well as a respective device and system for performing the method. Measurements are received. The measurements comprise current and/or voltage measurements at a first position along a transmission line for an electrical power system. A first impedance is computed from the received measurements. A fault location is determined from the computed first impedance and a first impedance boundary. Responsive to the determined fault location, a second impedance is computed. The fault location is redetermined from the computed second impedance and the first impedance boundary. The distance protection system is controlled based on the determined fault location or the re-determined fault location.

This application discloses a system that may comprise at least a portion of a supply network. The system may further comprise a load controller that controls current flow with a current level of I1 into a load network that provides power to one or more loads from the at least a portion of the supply network according to a preprogrammed load curve. The system may also comprise a protection system that isolates the at least a portion of the supply network from the load controller in response to detecting a current pattern that is inconsistent with the preprogrammed load curve.