Methods for determining a line fault of a power system. The methods include obtaining sampled values of voltages and currents of phases of a power line in the power system, determining a phase compensation voltage of a first phase and an interphase compensation voltage of an interphase loop between a second phase and a third phase, and detecting the line fault in the first phase and/or the interphase loop by comparing the phase compensation voltage and the interphase compensation voltage.

Circuits, methods, and apparatus that may provide power supply voltages in a safe and reliable manner that meets safety and regulatory concerns and does not exceed physical limitations of cables and other circuits and components used to provide the power supply voltages. One example may provide a cable having a sufficient number of conductors to provide power without exceeding a maximum current density for the conductors. Another example may provide a cable having more than the sufficient number of conductors in order to provide an amount of redundancy. Current sense circuits may be included for one or more conductors. When an excess current is sensed, a power source in the power supply may be shut down, the power source may be disconnected from one or more conductors, or both events may occur.

The present specification provides a method and device for determining a disturbance condition in a power transmission line. The method includes obtaining (302) a plurality of sample values corresponding to an electrical parameter measured in each phase. The method further includes determining (304) a plurality of magnitudes of the electrical parameter corresponding to each phase based on the corresponding plurality of sample values and determining (306) a plurality of difference values for each phase based on the corresponding plurality of magnitudes. The method includes processing (308) the plurality of difference values using a machine learning technique to determine the disturbance condition. The disturbance condition is one of a load change condition, a power swing condition and an electrical fault condition. The method also includes performing (310) at least one of a protection function and a control function based on the disturbance condition.

The disclosure describes a system for monitoring and mitigating damage to electrical utility structures and the surrounding environment. In some embodiments, the system includes fire boxes, arc sensors, angle switches, and disconnect switches configured to generate alert signals when a hazard is detected. In some embodiments, the system includes cameras configured to detect a hazard such as a fire or moving object. In some embodiments, the system includes light transmitters and light receivers positioned at a predetermined location away from power lines to detect objects that interrupt a line of site. In some embodiments, the system can electrically isolate a power line before a detected hazard impacts a power line.

In a digital-electricity power system, an electrical-current sample value is acquired along with a voltage sample value within a time window over which the electrical current and voltage are substantially unchanged. A transmission-line series voltage is derived from the difference between the voltage at the transmitter and the voltage at the receiver. Each transmission-line series voltage is divided by a corresponding stored electrical-current sample value to generate a ratio indicative of transmission-line series resistance. These steps are repeated, and the transmitter-disconnect device is placed in a non-conducting state if a difference in the ratio generated in one or more time periods exceeds a predetermined maximum, wherein exceeding the predetermined maximum is indicative of a series resistance fault. Alternatively, a series resistance value, determined by dividing a change in voltage over a change in current, is evaluated to detect a fault.

The present invention refers to a connection device installed on-board with respect to an electric wheelchair, designed and configured to allow the charging of a respective traction battery using a charge station or column for electric vehicles which implements the mode 3 of charging compliant with the IEC 61851-1 standard. The connection device attached to the wheelchair comprises a main body configured to be connected to a first wire portion for the electrical connection to the charge station. The main body further comprises an electrical circuit configured to simulate the performance of an electric vehicle and defined compliant with the IEC 61851-1 standard, edition 3, Annex 1, chapter A.2.3.

A wiring system for a vehicle is specified, which has a voltage source and an electrical load, whereby a need for the electrical load depends on an external condition. Furthermore, the wiring system has a load path with an electrical line, which connects the voltage source to the electrical load, and a first switching element, which is arranged in the load path, for disconnecting the electrical load from the voltage source, wherein a working range of the external condition is defined, within which the function of the electrical load is reasonable, and a control unit is arranged, which is designed in such a way that a switching on of the electrical load is prevented if the external condition lies outside the working range. Furthermore, a method for the design of an electrical line of such a wiring system is given.

A system includes a number of sensor units and a local controls station. The sensor units include one or more conductor sensors configured to monitor one or more parameters of a conductor in a power distribution system. The local control station includes a communication interface for communicating with the sensor units and a controller. The controller is configured to receive data from the sensing units, determine whether an event associated with one or more components of a power distribution network occurred based on the received data, and then determine whether the event requires protective action in response to determining that the event occurred. The controller determines whether the event occurred downstream of the local control station, and, in response to determining that the event requires protective action and occurred downstream of the local control station, control the one or more protective devices to perform a protective action.

An arrangement and method for zero sequence differential protection of a transmission line of a power system are disclosed. A zero sequence differential protection unit is configured to detect an internal fault of the transmission line using current measurements of each phase A, B, C of the transmission line. The zero sequence differential protection unit is configured to initiate a trip when an internal fault is detected. A phase selection unit is configured to determine whether or not any of the phases A, B, C of the transmission line is faulty using a comparison of differential values of the current measurements for each phase. The phase selection unit is configured to, based on the initiation of the trip, determine which of the phases A, B, C is faulty and to finalize the trip for any faulty phase.

The invention concerns a method for monitoring a cable strand containing multiple electrical lines, such that the cable strand is designed to conduct electrical energy generated by a generator in a wind turbine involving the steps: measuring the temperature of at least two of the electrical lines, comparing the temperatures of said lines, and determining whether the two temperatures deviate from one another by more than a predefined threshold.