A current control device brings, after a target current has been changed to an upper side, a solenoid into a full-on state at a first timing that arrives in a predetermined control transition cycle shorter than an on-off cycle, determines whether an excitation current has become equal to or larger than a full-on threshold larger than the target current, brings the solenoid into a full-off state at a first timing that arrives in a predetermined energization switching cycle shorter than the on-off cycle after the excitation current has become equal to or larger than the full-on threshold, determines whether the excitation current has become equal to or smaller than a full-off threshold smaller than the target current, and causes a transition to a steady control at a first timing that arrives in the control transition cycle after the excitation current has become equal to or smaller than the full-off threshold.

A current control device brings, after a target current has been changed to an upper side, a solenoid into a full-on state at a first timing that arrives in a predetermined control transition cycle shorter than an on-off cycle, determines whether an excitation current has become equal to or larger than a full-on threshold larger than the target current, brings the solenoid into a full-off state at a first timing that arrives in a predetermined energization switching cycle shorter than the on-off cycle after the excitation current has become equal to or larger than the full-on threshold, determines whether the excitation current has become equal to or smaller than a full-off threshold smaller than the target current, and causes a transition to a steady control at a first timing that arrives in the control transition cycle after the excitation current has become equal to or smaller than the full-off threshold.

A differential protection method for monitoring a line of a power grid. Current phasor measured values are captured at the ends of the line and transmitted to an evaluation device which is used to form a differential current value with current phasor measured values temporally allocated to one another. Time delay information indicating the time delay between local timers of the measuring devices is used for the temporal allocation of the current phasor measured values captured at different ends, and a fault signal indicating a fault affecting the line is generated if the differential current value exceeds a predefined threshold value. The reliability of the time synchronization is further increased by forming a quotient of the current phasor measured values to form an asymmetry variable, that is used to check a transit time difference of messages transmitted via the communication connection in different directions.

Systems and methods to disconnect a faulted region of a power grid are described. For example, a control system may obtain a set of regions of a power grid. The control system may obtain a current magnitude and a voltage magnitude of the power grid. The control system may detect a fault in the power grid based at least in part on the current magnitude. The control system may, from the set of regions, determine a faulted region that the fault is located within based on a voltage magnitude of one or more buses in the power grid, a net change in power with respect to time of one or more regions in the set of regions, or both. The control system may send one or more signals to electrically disconnect the faulted region from the power grid.

Systems, methods, and computer-readable media are disclosed for high-speed falling conductor protection in electric distribution systems. An example method may include calculating, by a processor, at a first time, and for each phase, one or more first impedance values associated with one or more terminals of a transmission line. The example method may also include calculating, by the processor, at a second time, and for each phase, one or more second impedance values associated with the one or more terminals. The example method may also include determining, by the processor, that a rate of change of an impedance of the one or more terminals is greater than a threshold rate of change. The example method may also include determining, by the processor and based on the determination that the rate of change of the one or more terminals is greater than the threshold rate of change, that the transmission line has broken. The example method may also include sending, by the processor and based on the determination that the transmission line has broken, a signal to de-energize the transmission line before a broken conductor reaches a ground surface.

A stored electric energy distribution arrangement for distribution of stored electric energy on a vessel having one or more AC consumers, in the event of failure of a primary electric energy supply to the AC consumers has a DC-circuit. The DC circuit has a plurality of backup electric energy storage elements connected in a ring, for supplying stored electric energy to one or more AC consumers in the event of failure of the primary electric energy supply. A plurality of breaker systems are provided in the DC circuit for disconnecting one or more backup electric energy storage elements from the DC-circuit, in the event of a fault associated with that backup element.

In one embodiment, a network protector for a spot network includes a circuit breaker and a network protector relay coupled to the circuit breaker. The network protector relay is structured and configured to have network protector relay non-sensitive trip settings for controlling operation of the circuit breaker that will cause the network protector to remain closed when: (i) an angular difference (±) between a transformer phase-to-neutral voltage of the first feeder branch and a transformer phase-to-neutral voltage of the second feeder branch is less than or equal to a first threshold value, and (ii) a magnitude difference (±) between the transformer phase-to-neutral voltage of the feeder branch and the transformer phase-to-neutral voltage of the second feeder branch is less than or equal to a second threshold value.

In one embodiment, a network protector for a spot network includes a circuit breaker and a network protector relay coupled to the circuit breaker. The network protector relay is structured and configured to have network protector relay non-sensitive trip settings for controlling operation of the circuit breaker that will cause the network protector to remain closed when: (i) an angular difference (±) between a transformer phase-to-neutral voltage of the first feeder branch and a transformer phase-to-neutral voltage of the second feeder branch is less than or equal to a first threshold value, and (ii) a magnitude difference (±) between the transformer phase-to-neutral voltage of the feeder branch and the transformer phase-to-neutral voltage of the second feeder branch is less than or equal to a second threshold value.

An electrical protection method for detecting an electrical fault in an electrical installation includes: measuring electrical variables by way of an auxiliary protection device, the electrical variables being associated with phase conductors; automatically analysing the measured electrical variables in order to identify a condition representative of a short circuit between phase conductors; detecting an electrical fault, such as a short circuit between the three electrical phases associated with the phase conductors without any neutral conductor involved, based on the measured electrical variables; triggering the opening of a switching device of the auxiliary protection device when an electrical fault is identified in order to disconnect one of the phase conductors, the switching device being connected to one of the phase conductors.

An apparatus includes: a plurality of separable load break devices, each separable load break device including: a resettable current interruption device associated with operating states, the operating states including at least a first operating state that prevents current flow in the resettable current interruption device and a second operating state that allows current flow in the resettable current interruption device; a switch control configured to control the operating state of the resettable current interruption device; a connection interface configured to mechanically connect the load break device to a separate electrical device and to electrically connect the resettable current interruption device to the separate electrical device; and an electrical interface configured to electrically connect the resettable current interruption device to a load. The apparatus also includes a control system configured to provide electrically ganged operation of the plurality of load break devices.