A method and apparatus provide an improved way to monitor a circuit for deterioration and obtain an advance warning of the deterioration so that action can be taken before the circuit breaker may trip for the circuit. The method establishes a baseline for the circuit, including monitoring the zero crossing point for the voltage and current for the circuit. In operation, the circuit is monitored using the zero crossing point and this information is compared to the baseline to determine if a change has occurred. The baseline information establishes thresholds that signify that the circuit is deteriorating so that the appropriate signal can be provided so that an appropriate action can be taken, interrupt the circuit, take remedial action, etc.

A load center comprises a common instantaneous tripping unit that works on a principle of solid state switching. The load center further comprises a plurality of branches of branch circuit breakers each of which is coupled to the common instantaneous tripping unit via a corresponding high power connection and a corresponding low power connection such that the common instantaneous tripping unit feeds the plurality of branches at the same time. The common instantaneous tripping unit interrupts a short circuit fault in an interruption time which is significantly reduced thus reducing or eliminating chances for a personal injury during the short circuit fault.

A ground fault directionality detection method, a ground fault directionality detection device and a computer-readable storage medium for a small current grounding system are disclosed. The ground fault directionality detection method comprises sampling at least a part of a current signal to obtain a numerical matrix; providing the numerical matrix as an input to a ground fault directionality detection neural network; calculating a label vector corresponding to the numerical matrix by the ground fault directionality detection neural network, wherein the label vector indicates whether the current signal is an upstream fault current signal or a downstream fault current signal; receiving a ground fault confirmation signal by the ground fault directionality detection neural network; and outputting the label vector by the ground fault directionality detection neural network when the ground fault confirmation signal indicates that the current signal is a ground fault current signal.

An inrush current detection method, an inrush current detection device and a computer-readable storage medium for a transformer are disclosed. The inrush current detection method includes sampling at least a part of a current signal of the transformer to obtain a numerical matrix; providing the numerical matrix as an input to an inrush current detection neural network; and calculating and outputting a label vector corresponding to the numerical matrix by the inrush current detection neural network, wherein the label vector indicates whether the current signal is an inrush current.

A method for determining a control architecture for a network of protective relays of a power distribution system. The method includes receiving data specifying a topology of a plurality of relays in the network of protective relays. The method includes sequentially modelling each relay in the network of protective relays using a reinforcement learning algorithm, including modelling each relay as an agent configured to detect one or more local conditions on the power distribution system and configured to trip based on the one or more local conditions. The method includes determining, based on the sequential modelling, one or more control parameters for each relay in the network of protective relays.

An electrical power distribution system includes a plurality of circuit protection devices coupled between an electrical power source and a plurality of electrical loads. Each circuit protection device includes a trip unit, a network interface communicatively coupled to a communication network including the circuit protection devices, a processor, and a memory. The memory stores instructions that, when executed by the processor, cause the processor to store test operational parameters associated with the circuit protection device, receive a test message including test data representing an electrical condition in the electrical power distribution system, adjust the test operational parameters based on the test data to simulate a response of the trip unit to the electrical condition, generate circuit protection data based on the test data and the adjusted set of test operational parameters, and transmit the circuit protection data to at least one of the communication network and a remote access device.

The invention includes an output circuit that outputs an operation signal to a direct current breaker that interrupts a direct current main circuit, and a processor that samples, at predetermined time intervals, digital data wherein a value detected by a direct current transformer that detects a current of the direct current main circuit is measured as an input current, calculates a computed measurement value to be output to a display circuit, and outputs control information for executing a protection process using measurement value sampling data obtained by the sampling to the output circuit, and executes a protection process of the direct current main circuit at every sampling.

A photovoltaic array of photovoltaic solar cells; a smart dynamic programmable circuit breaker for electrically providing a pulsed 100 microseconds duration short circuit to the photovoltaic array electrical outputs, wherein a response time for the smart dynamic programmable circuit breaker is more than 1 millisecond when responding to a short circuit; a computer program comprising instructions that when executed by the processor perform functions that control the smart dynamic programmable circuit breaker, the computer program comprising: instructions to command the smart dynamic programmable circuit breaker to initiate the 100 microsecond pulsed short circuit; instructions to measure a current magnitude and current rise time of the smart photovoltaic system outputs during the 100 microsecond pulsed short circuit; and instructions to select a behavior curve from a plurality of smart dynamic programmable circuit breaker behavior curves 10% above the current magnitude and current rise time during the pulsed short circuit.

A method for protecting a server from damage by a liquid leak from a liquid-cooling unit of the server is provided. The server further includes a liquid leak sensor unit, a programmable logic circuit, and a power supply unit that supplies main power and standby power for the server. When a liquid leak is detected, the liquid leak sensor unit generates a main-power-off signal to the programmable logic circuit that causes the power supply unit to stop outputting the main power accordingly. The liquid leak sensor unit sends a total-power-off signal to the power supply unit to stop supply of the standby power after the power supply unit has stopped outputting the main power.

The wide application of power electronic components in power systems with renewable energy sources has changed the fault characteristics of conventional power systems, resulting in the performance degradation of conventional protections. To solve these problems, a novel principle of pilot protection based on structural similarity and square error criteria is provided. The structural similarity criterion utilizes the difference of fault characteristics between renewable sources and synchronous generators to identify internal faults, and the square error criterion is used to solve abnormal calculation of the conventional similarity based protection. Compared with conventional differential protections, the disclosed protection shows excellent performance in speed and reliability during various faults.