An electrical power network employing fault location, isolation and system restoration. The system includes a plurality of switching devices electrically coupled along a power line downstream of a fault interrupting device. The switching devices each have current and voltage sensing capability and the capability to provide pulse tests for detecting fault presence. The fault interrupting device performs reclosing operations, and when the plurality of switching devices detect fault presence a predetermined number of times in coordination with reclosing operations performed by the fault interrupting device and detect loss of voltage, each switching device opens. The fault interrupting device closes when the switching devices open, and the switching devices sequentially pulse test and close from a furthest upstream switching device when detecting return of voltage and no fault presence until a switching device closest to the fault pulse tests and detects fault presence and locks open.

Systems, methods, and computer-readable media are disclosed for high impedance detection in electric distribution systems. An example method may include calculating, by a processor, a relative randomness of a signal, wherein the relative randomness is a derivative of a first scale wavelet transform divided by an energy of the signal. The example method may also include calculating, by the processor, one or more scales of a wavelet transform of the signal. The example method may also include calculating, by the processor, one or more energy ratios between energy of the wavelet transform in the one or more scales. The example method may also include calculating, by the processor, a zero-crossing phase difference between a third harmonic and a fundamental component of the signal. The example method may also include determining, by the processor, that a high impedance fault occurs based on at least one of: the relative randomness, a comparison between the one or more scales of the wavelet transform, and the zero-crossing phase difference.

A DC power supply may use an input supply surge protection circuit that may be robust against positive and negative power surges. DC power may be provided through a first unidirectional circuit component such as a diode or selectively controlled MOSFET coupled in parallel with a transient voltage suppressor or Zener diode. The first unidirectional circuit component may have a first voltage rating and the transient voltage suppressor or Zener diode may have a second voltage rating lower than the first voltage rating. This may allow current to flow backward over the transient voltage suppressor or Zener diode to protect the first unidirectional circuit component from exposure to voltage beyond the first voltage rating in a power surge.

An arc fault detection system senses current flow in a power source branch and in one or more load branches in an electrical system. Over a frequency range divided into a predetermined number of frequency bins, a controller records and tallies the branch having largest magnitude of power spectral density for each frequency bin. The branch having highest total tally is determined to be the branch in which the arc fault occurred and can then safely be isolated from the electrical system.

A compound control circuit comprises an input end, a light-load signal processing circuit, a slow response circuit and a fast response circuit. The compound control circuit is mainly used as an additional circuit of a work control chip, so that although the work control chip only has a single overcurrent protection level, a compound function control of fast and slow speed, high and low level current protection and light-load signal stabilization can be generated through the compound control circuit, so as to meet the complex application environment and compatible requirements of the current power supply.

The present disclosure provides a battery detection device. The detection circuit is disposed on the battery and produces an impedance value variation quantity according to a deformation of the battery. The detection circuit includes four connection nodes. The first connection node and the third connection node are connected with the battery. A voltage variation quantity is produced between the second connection node and the fourth connection node according to the impedance value variation quantity. The protection circuit is connected with the second connection node and the fourth connection node. The protection circuit is in an ON state when the voltage variation quantity is greater than or equal to a cut-off voltage. The protection circuit is in an OFF state when the voltage variation quantity is less than the cut-off voltage, so that an operation state of the battery is changed accordingly.

In some examples, an electrical power system includes a power source and a load modulator configured to receive power from the power source and to deliver power to a load zone. The electrical power system also includes a controller configured to determine a software-controlled power flow limit for the load zone. The controller is further configured to receive information indicating the power delivered to the load zone and to cause the power delivered to the load zone to remain below the software-controlled power flow limit.

An integrated circuit includes an output terminal, an analog output circuit, a digital output circuit, and a protection circuit. The analog output circuit includes an output coupled to the output terminal. The digital output circuit includes an output. The protection circuit includes a protection transistor and a comparator circuit. The protection transistor includes a first terminal coupled to the output of the digital output circuit, a second terminal coupled to the output terminal, and a control terminal. The comparator circuit includes a first input coupled to the output terminal, a second input coupled to a reference current source, and an output coupled to the control terminal of the protection transistor.

A method for transferring data from an actuating element to a control unit activating the actuating element. The control unit activates an inductance contained in the actuating element, for the transfer of the data in the actuating element in parallel to the inductance, a load being connected in parallel, or not.

A method for controlled switching of a circuit breaker is described. The method includes initiating operation of the circuit breaker at an initiation time derivable from an initiation time function by calculating a value of the initiation time function with respect to a command instant. The initiation time function is a sum of the command instant and a command delay time. The initiation time function depends on a first parameter and a second parameter. At least one of: the partial derivative of the initiation time function with respect to the first parameter is dependent on the second parameter or the partial derivative of the initiation time function with respect to the second parameter is dependent on the first parameter. Further, a system for controlled switching according to the method and a circuit breaker including the system are described.