Method of controlling a wind power plant
A method of controlling a wind power plant including an energy storage device, the wind power plant being connected to a power grid and comprising one or more wind turbine generators that produce electrical power for delivery to the power grid, the method comprising: processing grid data related to the power grid to determine a probability forecast for a future state of the grid; and controlling charging and discharging of the energy storage device in accordance with the probability forecast.
1. A method of controlling a wind power plant including an energy storage device, the wind power plant being connected to a power grid and comprising one or more wind turbine generators that produce electrical power for delivery to the power grid, the method comprising:
processing grid data related to the power grid to determine a probability forecast for a future state of the power grid, wherein the probability forecast for the future state of the power grid provides an indication of relative probabilities of a range of future grid events possibly occurring on the power grid over a time window, wherein the range of future grid events includes: i) fault events resulting from under voltage or frequency on the power grid; and ii) at least one of the following grid events: changes in power consumption by loads connected to the power grid; adding new loads to the power grid; and real-time electricity price fluctuations associated with the power grid; and
controlling charging and discharging of the energy storage device in accordance with the probability forecast.
2. The method of claim 1 , comprising:
determining a set of chance-constraints relating to operation of the wind power plant;
determining respective limits for each chance-constraint of the set;
determining, based on each chance-constraint limit and the probability forecast, a set of device constraints relating to charging and/or discharging of the energy storage device; and
controlling charging and discharging of the energy storage device to avoid violating the device constraints.
3. The method of claim 2 , comprising:
solving an optimisation problem for controlling charging and discharging of the energy storage device, wherein the optimisation problem comprises the device constraints; and
controlling charging and discharging of the energy storage device based on a control output of the optimisation problem.
4. The method of claim 3 , comprising solving the optimization problem using a predictive algorithm.
5. The method of claim 4 , comprising simulating operation of the wind power plant using the predictive algorithm.
6. The method of claim 4 , wherein the predictive algorithm is based on a chance-constrained model predictive control strategy.
7. The method of claim 2 , wherein each limit defines a proportion of operation time of the wind power plant for which the respective chance-constraint may be violated.
8. The method of claim 2 , wherein each chance-constraint of the set of chance-constraints comprises a requirement to provide any of the following: virtual inertia; defined power output profiles during a voltage ride-through event; power-line flicker reduction; reactive power injection; grid oscillation damping; side-side torque damping; drivetrain torque damping; upward yaw control; and noise below a threshold level.
9. The method of claim 1 , comprising determining a state of charge setpoint for the energy storage device, and controlling charging and discharging of the energy storage device in accordance with the state of charge setpoint.
10. The method of claim 1 , wherein the probability forecast comprises any of: a cumulative distribution function; and a probability density function.
11. The method of claim 1 , comprising processing data indicative of wind conditions to determine a probability forecast for wind conditions, and controlling charging and discharging of the energy storage device in accordance with the probability forecast for wind conditions.
12. The method of claim 1 , comprising controlling charging and discharging of the energy storage device in accordance with a prescribed probability of violating one or more grid requirements.
13. The method of claim 1 , wherein the grid data comprises any of the following: data indicative of a state of the power grid; a ramp-rate limit with respect to the power delivered to the power grid; a request received from the power grid; grid design data; historical grid data; data indicative of a weak grid obtained from plant-level and/or turbine-level analysis; electricity pricing data; and user-entered forecasts indicative of planned changes to the power grid.
14. The method of claim 1 , comprising altering operation of one or more wind turbine generators of the wind power plant in accordance with the or each probability forecast, and controlling charging and discharging of the energy storage device in accordance with the altered operation of the or each wind turbine generator.
15. The method of claim 1 , wherein the energy storage device is electrically coupled to a point of common coupling at which the wind power plant connects to the power grid, or is integrated into a wind turbine generator of the wind power plant.
16. The method of claim 1 , wherein the probability forecast comprises a probability density function that indicates, over the time window, probabilities for wind gusts at different speeds, directions, and durations.
17. The method of claim 1 , wherein the range of future grid events includes a grid event associated with power and voltage oscillation caused by signals of different ones of the one or more wind turbine generators being combined.
18. A control system for a wind power plant including an energy storage device, the wind power plant being connected to a power grid and comprising one or more wind turbine generators that produce electrical power for delivery to the power grid, the control system comprising:
an input configured to receive grid data related to the power grid;
a processing module configured to:
process the grid data to determine a probability forecast for a future state of the grid, wherein the probability forecast for the future state of the power grid provides an indication of relative probabilities of a range of future grid events possibly occurring on the power grid over a time window, wherein the range of future grid events includes: i) fault events resulting from under voltage or frequency on the power grid; and ii) at least one of the following grid events: changes in power consumption by loads connected to the power grid; adding new loads to the power grid; and real-time electricity price fluctuations associated with the power grid; and
generate a control signal arranged to control charging and discharging of the energy storage device in accordance with the probability forecast; and
an output configured to output the control signal.
19. A wind power plant connected to a power grid, comprising:
an energy storage device;
at least one wind turbine, comprising:
a tower;
a nacelle disposed on the tower;
a generator disposed in the nacelle and configured to produce electrical power for delivery to the power grid;
a rotor coupled to the generator; and
a plurality of blades disposed at a distal end of the rotor; and
a control system, comprising:
an input configured to receive grid data related to the power grid;
a processing module configured to:
process the grid data to determine a probability forecast for a future state of the grid, wherein the probability forecast for the future state of the power grid provides an indication of relative probabilities of a range of future grid events possibly occurring on the power grid over a time window, wherein the range of future grid events includes: i) fault events resulting from under voltage or frequency on the power grid; and ii) at least one of the following grid events: changes in power consumption by loads connected to the power grid; adding new loads to the power grid; and real-time electricity price fluctuations associated with the power grid; and
generate a control signal arranged to control charging and discharging of the energy storage device in accordance with the probability forecast; and
an output configured to output the control signal.
20. The wind power plant of claim 19 , wherein the processing module is further configured to:
determine a set of chance-constraints relating to operation of the wind power plant;
determine respective limits for each chance-constraint of the set;
determine, based on each chance-constraint limit and the probability forecast, a set of device constraints relating to charging and/or discharging of the energy storage device; and
control charging and discharging of the energy storage device to avoid violating the device constraints.