Abstract: A variable speed wind turbine is provided. The wind turbine comprises a generator, a power converter for converting at least a portion of electrical power generated by the generator, an energy management arrangement coupled to the power converter, the energy management arrangement comprises an energy storage unit, and a controller. The controller is adapted to detect a power imbalance event and to transfer at least a portion of excess electrical energy generated by the generator to the energy storage unit to be stored therein when the power imbalance event is detected.

Abstract: A system for a wind turbine generator comprising: a set of voltage limiting elements, and a controller configured to bypass the voltage limiting elements when a line voltage is below a predetermined threshold, and configured to connect each voltage limiting element in series between a grid side converter and a turbine transformer of the wind turbine generator, and to determine a current control reference signal for controlling the grid side converter (to generate a determined current) when the line voltage is above the predetermined threshold.

Abstract: A method of operating a wind turbine is disclosed, the wind turbine comprising a power generator, a machine-side converter connected to the power generator, a line-side converter connected to a power grid through associated power components, and a DC-link connected between the machine-side converter and the line-side converter. The method includes monitoring the power grid for overvoltage events, and upon detecting an overvoltage event: (1) disabling active operation of the machine-side converter and the line-side converter, (2) enabling an AC load dump connected between the machine side converter and the power generator in order to dissipate power output from the power generator, (3) waiting for a waiting period, and (4) enabling active operation of the line-side converter and the machine converter when the overvoltage event ends within the waiting period.

Abstract: A wind turbine is provided. The wind turbine includes a generator, an output thereof being connectable to a power grid via a power transmission path, the power transmission path comprising a generator side converter coupled to the output of the generator, a grid side converter coupled to the power grid, and a DC link coupled between the generator side converter and the grid side converter. For diverting the generator power, a load dump arrangement is provided which includes at least one resistor, a plurality of switches, and a plurality of electrical connections which electrically connect the at least one resistor to the output of the generator and across the DC link via the plurality of switches. One common and configurable load dump is used for both converter system failures and grid failures. As compared to two separate load dumps for converter failures and grid failures, the single load dump will require a smaller space for a wind turbine.

Abstract: A controller arrangement of an electrical power transfer system (1) of a wind turbine is described. The wind turbine has an electrical generator and is connected to an electrical power grid, wherein the power transfer system (1) is arranged to transfer electrical power from the generator to the grid. The power transfer system (1) has at least two electrical elements (2-6), e.g. converters, and at least two controllers (15-17) each arranged to control at least one element (2-6).

Abstract: A power conversion system for converting electrical power from at least one power source includes a plurality of converter chains which couple the at least one power source to at least one load. At least two of the converter chains comprise an associated dissipating unit. The dissipating units are coupled via at least one switch. A controller is arranged to control the at least one switch to route power to be dissipated from one of the converter chains to the converter chain's associated dissipating unit, or to at least one of the other dissipating units, or to the converter chain's associated dissipating unit and to at least one of the other dissipating units, to cause corresponding dissipation of the power to be dissipated.

Abstract: According to an embodiment of the present invention, a method of operating a wind turbine including a power generator, a generator/machine side converter connected to the power generator, a grid/line side converter connected to a power grid through power components, and a DC-link connected between the machine side converter and the line side converter, comprises: Monitoring the power grid for overvoltage events; if an overvoltage event is detected disabling active operation of the machine side converter and of the line side converter, enabling an AC-load dump connected between the machine side converter and the power generator in order to dissipate active power output by the power generator into the AC-load dump, waiting for a waiting period, and enabling active operation of the line side converter and the machine side converter if the overvoltage ends within the waiting period.

Abstract: A system for a wind turbine generator comprising: a set of voltage limiting elements, and a controller configured to bypass the voltage limiting elements when a line voltage is below a predetermined threshold, and configured to connect each voltage limiting element in series between a grid side converter and a turbine transformer of the wind turbine generator, and to determine a current control reference signal for controlling the grid side converter (to generate a determined current) when the line voltage is above the predetermined threshold.

Abstract: A variable speed wind turbine is provided. The wind turbine comprises a generator, a power converter for converting at least a portion of electrical power generated by the generator, an energy management arrangement coupled to the power converter, the energy management arrangement comprises an energy storage unit, and a controller. The controller is adapted to detect a power imbalance event and to transfer at least a portion of excess electrical energy generated by the generator to the energy storage unit to be stored therein when the power imbalance event is detected.

Abstract: A power conversion system for converting electrical power from at least one power source includes a plurality of converter chains which couple the at least one power source to at least one load. At least two of the converter chains comprise an associated dissipating unit. The dissipating units are coupled via at least one switch. A controller is arranged to control the at least one switch to route power to be dissipated from one of the converter chains to the converter chain's associated dissipating unit, or to at least one of the other dissipating units, or to the converter chain's associated dissipating unit and to at least one of the other dissipating units, to cause corresponding dissipation of the power to be dissipated.

Abstract: A controller arrangement of an electrical power transfer system (1) of a wind turbine is described. The wind turbine has an electrical generator and is connected to an electrical power grid, wherein the power transfer system (1) is arranged to transfer electrical power from the generator to the grid. The power transfer system (1) has at least two electrical elements (2-6), e.g. converters, and at least two controllers (15-17) each arranged to control at least one element (2-6).