Control arrangement of a wind power plant by releasing stored power
A control arrangement of a wind power plant includes a number of wind turbines and a number of storage arrangements, which control arrangement includes a first monitoring module configured to determine a first power quantity stored in the rotating mass of a wind turbine; a computation module configured to predict a power curve progression during injection of the first power quantity into the grid and during a subsequent theoretical recovery phase; a second monitoring module configured to determine a second power quantity available in a storage arrangement; and a response management module configured to identify a time instant at which to commence release of the second power quantity in order to maintain the combined output power of the wind power plant at a pre-defined threshold during inertial response following a grid under-frequency event.
1 . A wind power plant comprising a control arrangement, at least one wind turbine and at least one storage arrangement, which control arrangement comprises:
a first monitoring module configured to determine a first power quantity stored in the rotating mass of the at least one wind turbine;
a computation module configured to predict a power curve progression during injection of the first power quantity determined by the first monitoring module into a grid and during a subsequent recovery phase;
a second monitoring module configured to determine a second power quantity available in the at least one storage arrangement; and
a response management module configured to identify, on the basis of the predicted power curve progression determined by the computational model and the second power quantity determined by the second monitoring module, a time instant at which to commence release of the second power quantity in order to maintain the combined output power of the wind power plant at a pre-defined threshold during inertial response following a grid under-frequency event, and wherein the at least one storage arrangement comprises a super capacitor, a battery and/or a flywheel.
2 . The control arrangement according to claim 1 , wherein the pre-defined threshold is a power output level preceding the grid under-frequency event.
3 . The control arrangement according to claim 1 , wherein the pre-defined threshold comprises at least 90%, at least 95%, or at least 99% of a power output level preceding the grid under-frequency event.
4 . The control arrangement according to claim 1 , configured to provide at least the first monitoring module with operating parameters of the wind power plant.
5 . The control arrangement according to claim 1 , wherein operating parameters comprise wind speed, pitch angle, aerodynamic rotor velocity, aerodynamic rotor deceleration rate and/or generator rotor velocity.
6 . A method of controlling a wind power plant to provide inertial response following a grid under-frequency event, the wind power plant comprising at least one wind turbine and at least one storage arrangement, which method comprises the steps of:
determining a first power quantity stored in the rotating mass of the at least one wind turbine;
predicting the power curve progression during release of the first power quantity and during subsequent recovery;
determining a second power quantity available in the at least one storage arrangement; and,
on the basis of the predicted power curve progression and the second power quantity, identifying a time instant at which to commence release of the second power quantity in order to maintain the combined output power of the wind power plant at a pre-defined threshold, wherein the at least one storage arrangement comprises a super capacitor, a battery and/or a flywheel.
7 . The method according to claim 6 , wherein the power curve progression is computed at least on the basis of current operating parameters.
8 . The method according to claim 6 , wherein current operating parameters comprise wind speed, aerodynamic rotor velocity, aerodynamic rotor deceleration rate and/or generator rotor velocity.
9 . The method according to claim 6 , wherein the step of predicting the power curve progression comprises a step of identifying a time at which the power output will decrease to a previous output power level.
10 . The method according to claim 6 , wherein the step of predicting the power curve progression comprises a step of computing a minimum power output.
11 . The method according to claim 6 , wherein the at least one storage arrangement further comprises an additional wind turbine and further comprising a step of controlling the rotating mass of the additional wind turbine.
12 . The method according to claim 6 , wherein the at least one wind turbine comprises a grid-forming inverter, and wherein the grid-forming inverter of the at least one wind turbine is operated in grid-forming mode.
13 . The method according to claim 6 , wherein the at least one storage arrangement comprises a grid-forming inverter, and wherein the grid-forming inverter of the at least one storage arrangement is operated in grid-forming mode.
14 . A computer program product, comprising a computer readable hardware storage device having computer readable program code stored therein, said program code executable by a processor of a computer system comprising a computer program that is directly loadable into a memory of the control arrangement according to claim 1 and which comprises program elements for performing steps when the computer program is executed by the control arrangement.