To provide a DC power distribution system that distributes power from a power supply device to a load device via a distribution network, the DC power distribution system including: a measuring instrument that is provided in the distribution network; and a control device that includes a determination unit that acquires, through optical fiber, a voltage value and a current value measured by the measuring instrument, and determines an operation state in the DC power distribution system on the basis of a waveform indicating a change in the voltage value and a waveform indicating a change in the current value.

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.

There is provided a method of operating a reconfigurable differential protection scheme for carrying out differential protection of an electrical power network, the electrical power network comprising terminals, each of the terminals configured to be in communication with each other within a communications network. The method includes controlling the differential protection scheme to deactivate the differential protection, and selecting a terminal to be configured out of or into the differential protection scheme. The method also includes communicating reconfiguration information among the terminals, the reconfiguration information including the selection of the terminal to be configured out of or into the differential protection scheme. The method also includes modifying a respective differential protection algorithm at each of the non-selected terminals so as to configure the selected terminal out of or into the differential protection scheme, and controlling the differential protection scheme to reactivate the differential protection.

There is provided a method of operating a reconfigurable differential protection scheme for carrying out differential protection of an electrical power network, the electrical power network comprising terminals, each of the terminals configured to be in communication with each other within a communications network. The method includes controlling the differential protection scheme to deactivate the differential protection, and selecting a terminal to be configured out of or into the differential protection scheme. The method also includes communicating reconfiguration information among the terminals, the reconfiguration information including the selection of the terminal to be configured out of or into the differential protection scheme. The method also includes modifying a respective differential protection algorithm at each of the non-selected terminals so as to configure the selected terminal out of or into the differential protection scheme, and controlling the differential protection scheme to reactivate the differential protection.

A method and a system for protecting an electrical distribution network, the system including sources of electrical energy, loads and protection devices, each having a nominal trip timer and being configured to supply signals of detection of the presence and direction of a fault current. The system determines monitoring points and a fault condition associated with each monitoring point directly connected to several protection devices, defined by rules relating to the presence and the direction of the fault current detected by each protection device in the vicinity of the monitoring point, and, when a fault condition is confirmed, trips as a priority, with a trip timer less than the nominal trip timer, the opening of at least one of the monitoring devices in the vicinity of the fault point.

An integrated circuit-based nano-relay, comprising: an integrated circuit system of the nano-relay constructed according to an integrated circuit module built from a combinational logic circuit. An integrated power data processing algorithm is called by means of the integrated circuit module to perform signal processing on an input power signal, and power service data is output, that is, an integrated circuit is mainly constructed by means of the combinational logic circuit, the protection logic of the nano-relay is achieved by means of a hardware circuit module, and a response speed of the relay is improved.

An over-current protection apparatus constituted of: a transistor disposed on a substrate; a first thermal sense device arranged to sense a temperature reflective of a junction temperature of the transistor; a second thermal sense device arranged to sense a temperature reflective of a temperature of a casing surrounding the substrate; and a control circuitry, arranged to alternately: responsive to the sensed temperature by the first thermal sense device and the sensed temperature of the second thermal sense device being indicative that the temperature difference between the transistor junction and the substrate casing is greater than a predetermined value, switch off the transistor; and responsive to the sensed temperature by the first thermal sense device and the sensed temperature by the second thermal sense device being indicative that the temperature difference between the transistor junction and the substrate casing is not greater than the predetermined value, switch on the transistor.

An RF phase offset detection system, which includes a first RF phase detector and a second RF phase detector, and measures a first phase offset between a first RF signal and a second RF signal, is disclosed. Each of the first RF signal and the second RF signal has a common RF frequency. The first RF phase detector detects and filters the first RF signal and the second RF signal to provide a first detection signal. The second RF phase detector receives and phase-shifts the second RF signal to provide a phase-shifted RF signal. The second RF phase detector further detects and filters the first RF signal and the phase-shifted RF signal to provide a second detection signal, such that a combination of the first detection signal and the second detection signal is representative of the first phase offset.

A photovoltaic power generation system includes a plurality of photovoltaic arrays, a plurality of shutdown units and an inverter. The shutdown unit is adjacent to the corresponding photovoltaic array, connected in parallel with the corresponding photovoltaic array, and electrically connected to the inverter via high voltage wires; the photovoltaic power generation system further includes a control unit configured to receive a detection signal indicating a state of the AC side of the inverter, monitor whether the AC side of the inverter is in a power-off state according to the detection signal, and generate a first power-off signal when the AC side of the inverter is in the power-off state; and the shutdown units are configured to receive the first power-off signal, and stop a power transmission from the photovoltaic arrays to the inverter according to the first power-off signal.

A fault location of a fault on a line of an electrical energy supply network is determined from measured current and voltage values at the first and second line ends. Highly accurate fault location with measured values from both line ends is provided even in the absence of temporal synchronization of the measurements at the line ends. Characteristics of first and second fictitious fault voltage values present at a fictitious fault location on the line are defined using the first and second current and voltage values. A fictitious fault location is determined for which the characteristic of the first fictitious fault voltage values corresponds most closely to the characteristic of the second fictitious fault voltage values. The fictitious fault location is used as the actual fault location. We also describe a correspondingly configured device and a system for determining a fault location.