A method and device for timing in time-varying distance protection based on multiple lines of a tower. The method includes: collecting an instantaneous current value at a time-varying distance protection installation location in the multiple lines of the tower, and acquiring preset parameters; calculating, according to the preset parameters and a multi-line ranging model, a multi-line ranging result; calculating, according to the preset parameters, the multi-line ranging result, and an adaptive calculation model, time of a section-II distance protection action and final time of a section-III distance protection action; and determining, according to the instantaneous current value, the preset parameters, and a cross-line failure auxiliary criterion model, final time of the section-II distance protection action.

Disclosed herein is a system for time aligning electric power system measurements at an intelligent electronic device (IED) using samples and sample time offset from merging units. The merging units do not require access to a common time signal. The IED does not require storage of a communication latency with the merging units. The sample time offset corresponds to a latency between obtaining the sample and receipt of the sample at the IED. The IED aligns samples from various merging units using sample time offset values communicated from the merging units to the IED. The IED performs monitoring and protection functions using the time aligned samples.

A circuit includes processing circuitry is sensitive to a regulated voltage at the output node and to a temperature of the circuit. The processing circuit is configured to provide voltage and temperature sensing signals indicative of the regulated voltage at the output node and the temperature of the circuit. The processing circuitry is configured to assume i) a first state, as a result of the voltage sensing signal reaching a voltage threshold, ii) a second state, as a result of the temperature detection signal reaching a temperature threshold, or iii) a third state, as a result of both the voltage and the temperature sensing signals failing to reach the thresholds. The circuit comprises a warning output coupled to a warning signal generation network controlled by the processing circuitry.

A method for quantifying power quality events in an electrical system including a plurality of intelligent electronic devices (IEDs) includes processing electrical measurement data from or derived from energy-related signals captured by at least one first IED of the plurality of IEDs to identify a power quality event at a first point of installation of the at least one first IED in the electrical system. An impact of the power quality event at a second point of installation in the electrical system is determined based on an evaluation of electrical measurement data from or derived from energy-related signals captured by at least one second IED of the plurality of IEDs at the second point of installation proximate to a determined time of occurrence of the power quality event at the first point of installation.

A method for characterizing power quality events in an electrical system includes deriving electrical measurement data for at least one first virtual meter in an electrical system from (a) electrical measurement data from or derived from energy-related signals captured by at least one first IED in the electrical system, and (b) electrical measurement data from or derived from energy-related signals captured by at least one second IED in the electrical system. In embodiments, the at least one first IED is installed at a first metering point in the electrical system, the at least one second IED is installed at a second metering point in the electrical system, and the at least one first virtual meter is derived or located at a third metering point in the electrical system. The derived electrical measurement data may be used to generate or update a dynamic tolerance curve associated with the third metering point.

Systems and methods may mitigate risk of fire caused by an electric power system. In one embodiment, a system may include an intelligent electronic device (IED). The IED includes a communication subsystem to receive a signal from a sensor related to a condition of the electric conductor. A processing subsystem in communication with the communication subsystem may operate in at least two modes comprising a high security mode and a fire prevention mode. In the fire prevention mode, the IED may interrupt a flow of electric current based on the signal from the at least one sensor associated with the electric conductor. In the high security mode, the system may interrupt a flow of electric current based on the signal from the at least one sensor associated with the electric conductor and based on a second condition relating to the electric conductor.

A device, such as a link box, with health monitoring has a housing defining an interior space, at least one surge arrester positioned in the interior space, at least one contactless temperature sensor positioned to contactlessly measure a temperature of the at least one surge arrester and generate temperature data therefrom, and at least one controller connected to the at least one contactless temperature sensor and configured to receive the temperature data.

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 metering device in the electrical system to generate at least one dynamic tolerance curve. Each dynamic tolerance curve of the at least one dynamic tolerance curve characterizes a response characteristic of the electrical system at a respective metering point in the electrical system. The method also includes analyzing the at least one dynamic tolerance curve to identify special cases which require further evaluation(s)/clarification to be discernable and/or actionable. The at least one dynamic tolerance curve may be regenerated or updated, and/or new or additional dynamic tolerance curves may be generated, to provide the further clarification. One or more actions affecting at least one component in the electrical system may be performed in response to an analysis of the curve(s).

An electronic device includes a monitoring unit that monitors a voltage of a first terminal that receives power supplied from a power supply apparatus, and a control unit that performs control so as to stop the power supply from the power supply apparatus if a voltage variation per unit time of the first terminal is not less than a first predetermined value or the voltage of the first terminal is not less than a second predetermined value.

An example embodiment is a voice appliance including: a plurality of user interface devices comprising at least a microphone and a speaker; a plug for receiving power to the appliance or load; and a communication subsystem configured for wired communication with an electrical receptacle through the plug when plugged into the electrical receptacle. An electrical receptacle for connection to power lines comprises: at least one plug outlet configured to provide DC output, wherein the at least one plug outlet is configured to provide access to a wired communication network defined by at least one of the power lines. The plug outlet can be a Universal Serial Bus (USB) plug outlet to connect to a mobile device or a removable USB memory device. An intelligent junction box at the circuit breaker panel is configured to perform dynamic power allocation and power line communication.