A system and method for protection of an electrical grid. A respective one of the substations of the system including: a first directional protective relay to generate a signal operating on the electrical power line between the respective one of the substations and a remote one of the substations; a cyber health module to receive remote signals from two remote directional protective relays and output a reliability signal based on consistency of the remote signals and a status of the communication channels being operational; a circuit breaker to interrupt electrical power flow when directed; and a comparison circuit to receive signals and to direct the circuit breaker to interrupt electrical power flow when the reliability signal from the cyber health module indicates consistency, the first directional protective relay indicates fault, and at least one of the remote directional protective relays indicate fault.

Transmission-line voltage measurements in a digital-electricity power system are validated by acquiring a series of transmission-line voltage measurements during a sample period when a transmitter-disconnect device is in a non-conducting state. A numerical analysis is performed to determine a point in time at which AC components in the transmission line have diminished and at which the primary change in the transmission-line voltage measurement values is due to DC decay. A receiver acquires a series of receiver-voltage measurements during the same sample period; and a numerical analysis is performed on the receiver-voltage measurements to determine the point in time at which the AC components have diminished and where the primary change in the transmission-line voltage measurement values is due to DC decay. The transmitter-disconnect device is then placed in a non-conducting state based on an evaluation of those measurements.

There is provided mechanisms for time-synchronized communication of packets between a first substation and a second substation interconnected by a communication channel. Samples obtained within the second substation are provided with time information associated with a common reference clock and sent to the first substation, at which a time-wise synchronization of the received samples with samples obtained within the first substation is performed by means of the time information and a time difference between the common reference clock and a local reference clock of the first substation.

An electrical protection system arranged to detect and isolate faults either in a electrical power distribution. The system comprises at least a first busbar and a second busbar in electrical communication with each other through s powerline having a first end electrically coupled to the first busbar by a first circuit breaker and a second end connected to the second busbar by a second circuit breaker. It is connected to the at least two busbars, and configured to simultaneously collect/determine a first electrical quantity at each of the at least two busbars and compare the collected/determined electrical quantity to a second. When the first electrical quantity value less than the second quantity value, the system causes the first and second circuit breakers to open so as to decouple the electrical connection between first and second busbars. The system 100 detects and isolates fault efficiently while using voltage measurements.

A system and method for protection of an electrical grid. A respective one of the substations of the system including: a first directional protective relay to generate a signal operating on the electrical power line between the respective one of the substations and a remote one of the substations; a cyber health module to receive remote signals from two remote directional protective relays and output a reliability signal based on consistency of the remote signals and a status of the communication channels being operational; a circuit breaker to interrupt electrical power flow when directed; and a comparison circuit to receive signals and to direct the circuit breaker to interrupt electrical power flow when the reliability signal from the cyber health module indicates consistency, the first directional protective relay indicates fault, and at least one of the remote directional protective relays indicate fault.

A terminal obtains a parameter from a charger, including at least one of an input voltage value and an output current value of the charger and a temperature value of a charging output port of the charger. When a parameter value is greater than a threshold, the terminal terminates a charging process based on a relationship between a corresponding threshold and at least one of a difference between the output current value of the charger and an input current value of the terminal, a power loss from the charger to the terminal, and a temperature value.

The present disclosure pertains to systems and methods for supervising protective elements in electric power systems. In one embodiment, a system may be configured to selectively enable a protective action an electric power system. The system may include a data acquisition subsystem receive a plurality of representations of electrical conditions associated with at least a portion of the electric power delivery system. An incremental quantities module may calculate incremental quantities from the plurality of representations. A protective module may be configured to detect an event, to determine an incremental quantities value during the event, and to determine a time-varying threshold. The incremental quantities value during the event may be compared with the time-varying threshold, and a protective action module may be enabled to implement a protective action when the value of the incremental quantities value during the event exceeds the time-varying threshold.

An example method of operating a power distribution system including a plurality of source and tie circuit protection devices coupled between at least one source and a protection zone is disclosed. The protection zone includes a distribution bus and a plurality of feeder circuit protection devices coupled between the distribution bus and a plurality of loads. The method includes determining an electric current flowing through each source and tie circuit protection device, determining whether any of the feeder circuit protection devices is outputting a ZSI blocking signal, and controlling operation of the plurality of source and tie circuit protection devices according to an enhanced partial differential protection scheme based on a combination of the determined currents through the source and tie circuit protection devices and the determination of whether any of the feeder circuit protection devices is outputting a ZSI blocking signal.

A differential protection method for generating a fault signal includes measuring current measurements at least at two different measuring points of a multiphase transformer for each phase. The current measurements for each phase are used to form differential current values and stabilization values. The fault signal is generated if it is determined during a trigger region check that a measurement pair of at least one of the phases, being formed by using one of the differential current values and the associated stabilization value in each case, is in a predefined trigger region. In order to be able to selectively and reliably distinguish an external fault from an internal fault, the transformer has a grounded star point and a zero system current flowing through the star point is used to form the stabilization values. A corresponding differential protection device is provided for performing the differential protection method.

A differential protection device monitors a first object to be protected in an electrical energy supply network. The differential protection device has a measuring unit configured to acquire measurement values at one end of the first object to be protected, a communication unit configured to exchange measurement values with a differential protection device arranged at another end of the first object to be protected, the communication unit has a physical interface for transmitting and receiving the measurement values, and an evaluation unit configured to form a differential value and to generate a fault signal indicating a fault with regard to the first object to be protected if the differential value exceeds a predefined threshold value. Ideally, the differential protection device is configured to monitor further objects to be protected and to exchange respective further measurement values with regard to each further object to be protected.