H02J3/0012

PROTECTION SYSTEM AND METHOD FOR ELECTRICAL POWER PLANT
20220320852 · 2022-10-06 ·

An apparatus for managing a plurality of electric power generators is configured to receive measurements of a plurality of parameters related to performance of one or more of a plurality of generators and detect, based on the measurements, that values of at least two of the plurality of parameters measured for a first generator of the one or more generators do not match respective predetermined values of the at least two parameters for the first generator. In response to the detecting, the apparatus determines that the first generator is faulty and generates a signal to perform at least one of shutting down the first generator or disconnecting the first generator from at least one second generator of the plurality of generators, in response to determining that the first generator is faulty.

CONVERTER AND METHOD OF OPERATING A CONVERTER

A converter has an AC side to connect to an AC network. A converter control is configured to set a current reference limit to limit a converter current. The converter control is configured to reduce the limit in case a fault is detected in the AC network. There is also described a combination of the converter in a power system with a renewable power source and a corresponding method of operating a converter in a power system with a renewable power source.

POWER SYSTEM STABILIZING SYSTEM

A power system stabilizing system includes an accident detector, a power restriction target selector, a cutoff controller, and a reconnection controller. The accident detector is configured to detect a system accident of a power system. The power restriction target selector is configured to select power restriction targets which are required for stability maintenance of the power system out of a plurality of power supplies included in the power system or connected to the power system according to a type of the system accident detected by the accident detector. The cutoff controller is configured to cut off the power restriction targets selected by the power restriction target selector. A system restoration checker is configured to check that the power system has been restored from the system accident on the basis of system information of the power system. The reconnection controller is configured to reconnect some or all of the power restriction targets cut off by the cutoff controller when the system restoration checker checks that the power system has been restored from the system accident.

Defined switch position in a wind farm prior to failure of the DC power supply

A method for controlling a wind power installation or a wind farm is provided. The method includes establishing that there is a grid fault within an electrical power supply grid operated by a grid operator and to which the wind power installation or the wind farm is electrically connected via a point of common coupling; switching electrical switches of the wind power installation or the wind farm using a control unit of the wind power installation or the wind farm which is operated by a low-voltage power supply, so that the wind power installation or the wind farm is voltage-free; testing an electrical store for ensuring the low-voltage power supply once the grid fault has been established; and switching further electrical switches of the wind power installation or the wind farm to a predefined switching state in which start-up of the wind power installation or the wind farm is possible.

Single phase fault isolation and restoration with loop avoidance for multiple tie-in devices

A method for controlling a power distribution network includes receiving, via an electronic processor, a fault indication associated with a fault from a first isolation device of a plurality of isolation devices. The processor identifies a first subset of a plurality of phases associated with the fault indication and a second subset not associated with the fault indication. The processor sends a first open command to each member of a set of downstream isolation devices for each phase in the first subset. The processor identifies a plurality of tie-in isolation devices to be closed to restore power. Responsive to identifying a first potential loop configuration, for each of the plurality of tie-in devices, the processor sends a close command to the tie-in isolation device for each of the plurality of phases and sends a second open command to the associated downstream isolation device for each phase in the second subset.

Distance-to-fault power outage notification
11641107 · 2023-05-02 · ·

Systems and methods comprising a metering device located on an electricity distribution grid, the metering device comprising one or more processors and memory. The metering device can detect a drop in characteristic of electricity below a threshold indicating a fault on the electricity distribution grid. The metering device can generate, responsive to the drop in the characteristic of electricity below the threshold, a time series of a rate of change of the characteristic of electricity for a predetermined number of cycles subsequent to the detection of the drop. The metering device can determine, based on a comparison of the time series of the rate of change with a predetermined pattern, a location of the metering device on the electricity distribution grid relative to a location of the fault on the electricity distribution grid.

Electrical power system with improved functional security

To improve functional security in electric power systems, a fault detector is provided in the electric power system that is connected to the data communication bus and that evaluates streamed values of at least one process parameter. In order to detect an electric fault in the electric power system, the fault detector is arranged to send a fault present indication to the switching element when an electric fault is detected. The fault present indication is sent to and received by the switching element, before the tripping operation of the switching element is triggered upon receipt of the switching command from the automation system, and the switching element triggers the tripping operation of the switching element only when a fault present indication has been received.

Closed loop restoration

A system and method for restoring power in a closed-loop power distribution network. The network includes at least two power sources, at least one feeder and a plurality of switching devices positioned along the at least one feeder and being in communications with each other. The method performs a radial restoration process for restoring power and then determines that at least one of the sections is not receiving power after the radial restoration process has been performed. The method estimates power flow through each switching device and determines an available power capacity from each switching device. The method then determines if the unpowered sections can be powered by any of their neighbor and non-neighbor devices. The method virtually closes the switching devices to power the unpowered sections and updates the estimation of power flow through each switching device and determination of available power capacity from each switching device.

WIND TURBINE POWER GENERATION COMPRISING AN AC-DC-AC CONVERTER AND A TRANSFORMER WITH A TAP CHANGER

A method of operating a power generating system for a wind turbine connected to an electrical grid, the power generating system comprising a power generator, a converter, a transformer and a tap changer, the method comprising; when operating the power generating system in a grid-forming configuration, monitoring a signal for detecting a voltage of the electrical grid which requires an increase in output voltage from the power generating system in order to maintain the grid voltage within a predetermined voltage range; and operating the tap changer to tap-up the transformer to provide at least part of the voltage increase required to maintain the grid voltage within the predetermined voltage range.

MEDIUM-VOLTAGE PHOTOVOLTAIC GRID-CONNECTED INVERTER SYSTEM AND PHOTOVOLTAIC POWER GENERATION SYSTEM
20230134016 · 2023-05-04 · ·

A medium-voltage grid-connected photovoltaic inverter system includes: a photovoltaic inverter, a medium-voltage transformer, a medium-voltage switch, and an inverter grid-connected controller. A direct current input terminal of the photovoltaic inverter is connected to a direct current bus. A low-voltage side of the medium-voltage transformer is connected to an alternating current output terminal of the photovoltaic inverter. An input terminal of the medium-voltage switch is connected to a high-voltage side of the medium-voltage transformer, and an output terminal of the medium-voltage switch is configured to be connected to a medium-voltage grid. A current sensor is integrated in the medium-voltage switch to detect a grid-connected current of the photovoltaic inverter system and output a current detection signal.