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Mads M. Pedersen authoredMads M. Pedersen authored
wind_farm_model.py 9.19 KiB
from abc import abstractmethod, ABC
from py_wake.site._site import Site, LocalWind
from py_wake.wind_turbines import WindTurbines
import numpy as np
from py_wake.flow_map import FlowMap, HorizontalGrid
class WindFarmModel(ABC):
"""Base class for RANS and engineering flow models"""
def __init__(self, site, windTurbines):
assert isinstance(site, Site)
assert isinstance(windTurbines, WindTurbines)
self.site = site
self.windTurbines = windTurbines
def __call__(self, x, y, h=None, type=0, wd=None, ws=None, yaw_ilk=None):
"""Run the wind farm simulation
Parameters
----------
x : array_like
Wind turbine x positions
y : array_like
Wind turbine y positions
h : array_like, optional
Wind turbine hub heights
type : int or array_like, optional
Wind turbine type, default is 0
wd : int or array_like
Wind direction(s)
ws : int, float or array_like
Wind speed(s)
Returns
-------
SimulationResult
"""
assert len(x) == len(y)
type, h, _ = self.windTurbines.get_defaults(len(x), type, h)
wd, ws = self.site.get_defaults(wd, ws)
if len(x) == 0:
wd, ws = np.atleast_1d(wd), np.atleast_1d(ws)
z = np.zeros((0, len(wd), len(ws)))
localWind = LocalWind(z, z, z, z)
return SimulationResult(self, localWind=localWind,
x_i=x, y_i=y, h_i=h, type_i=type, yaw_ilk=yaw_ilk,
wd=wd, ws=ws,
WS_eff_ilk=z, TI_eff_ilk=z,
power_ilk=z, ct_ilk=z)
WS_eff_ilk, TI_eff_ilk, power_ilk, ct_ilk, localWind = self.calc_wt_interaction(
x_i=x, y_i=y, h_i=h, type_i=type, yaw_ilk=yaw_ilk, wd=wd, ws=ws)
return SimulationResult(self, localWind=localWind,
x_i=x, y_i=y, h_i=h, type_i=type, yaw_ilk=yaw_ilk,
wd=wd, ws=ws,
WS_eff_ilk=WS_eff_ilk, TI_eff_ilk=TI_eff_ilk,
power_ilk=power_ilk, ct_ilk=ct_ilk)
@abstractmethod
def calc_wt_interaction(self, x_i, y_i, h_i=None, type_i=None, yaw_ilk=None, wd=None, ws=None):
"""Calculate effective wind speed, turbulence intensity,
power and thrust coefficient, and local site parameters
Typical users should not call this function directly, but by calling the
windFarmModel object (invokes the __call__() function above)
which returns a nice SimulationResult object
Parameters
----------
x_i : array_like
X position of wind turbines
y_i : array_like
Y position of wind turbines
h_i : array_like or None, optional
Hub height of wind turbines\n
If None, default, the standard hub height is used
type_i : array_like or None, optional
Wind turbine types\n
If None, default, the first type is used (type=0)
wd : int, float, array_like or None
Wind directions(s)\n
If None, default, the wake is calculated for site.default_wd
ws : int, float, array_like or None
Wind speed(s)\n
If None, default, the wake is calculated for site.default_ws
Returns
-------
WS_eff_ilk : array_like
Effective wind speeds [m/s]
TI_eff_ilk : array_like
Turbulence intensities. Should be effective, but not implemented yet
power_ilk : array_like
Power productions [w]
ct_ilk : array_like
Thrust coefficients
localWind : LocalWind
Local free-flow wind
"""
class SimulationResult():
"""Simulation result returned when calling a WindFarmModel object"""
def __init__(self, windFarmModel, localWind, x_i, y_i, h_i, type_i, yaw_ilk,
wd, ws, WS_eff_ilk, TI_eff_ilk, power_ilk, ct_ilk):
self.windFarmModel = windFarmModel
self.localWind = localWind
self.x_i = x_i
self.y_i = y_i
self.h_i = h_i
self.type_i = type_i
self.yaw_ilk = yaw_ilk
self.WS_eff_ilk = WS_eff_ilk
self.TI_eff_ilk = TI_eff_ilk
self.power_ilk = power_ilk
self.ct_ilk = ct_ilk
self.wd = wd
self.ws = ws
def aep_ilk(self, normalize_probabilities=False, with_wake_loss=True):
"""Anual Energy Production of all turbines (i), wind directions (l) and wind speeds (k) in in GWh
Parameters
----------
normalize_propabilities : Optional bool, defaults to False
In case only a subset of all wind speeds and/or wind directions is simulated,
this parameter determines whether the returned AEP represents the energy produced in the fraction
of a year where these flow cases occur or a whole year of only these cases.
If for example, wd=[0], then
- False means that the AEP only includes energy from the faction of year\n
with northern wind (359.5-0.5deg), i.e. no power is produced the rest of the year.
- True means that the AEP represents a whole year of northen wind.
with_wake_loss : Optional bool, defaults to True
If True, wake loss is included, i.e. power is calculated using local effective wind speed\n
If False, wake loss is neglected, i.e. power is calculated using local free flow wind speed
"""
if normalize_probabilities:
norm = self.localWind.P_ilk.sum((1, 2))[:, np.newaxis, np.newaxis]
else:
norm = 1
if with_wake_loss:
return self.power_ilk * self.localWind.P_ilk / norm * 24 * 365 * 1e-9
else:
power_ilk = self.windFarmModel.windTurbines.power(self.localWind.WS_ilk, self.type_i)
return power_ilk * self.localWind.P_ilk / norm * 24 * 365 * 1e-9
def aep(self, normalize_probabilities=False, with_wake_loss=True):
"""Anual Energy Production (sum of all wind turbines, directions and speeds) in GWh.
See aep_ilk
"""
return self.aep_ilk(normalize_probabilities, with_wake_loss).sum()
def flow_map(self, grid=None, wd=None, ws=None):
"""Return a FlowMap object with WS_eff and TI_eff of all grid points
Parameters
----------
grid : Grid or tuple(X, Y, x, y, h)
Grid, e.g. HorizontalGrid or\n
tuple(X, Y, x, y, h) where X, Y is the meshgrid for visualizing data\n
and x, y, h are the flattened grid points
See Also
--------
pywake.wind_farm_models.flow_map.FlowMap
"""
if grid is None:
grid = HorizontalGrid()
if isinstance(grid, HorizontalGrid):
plane = grid.plane
grid = grid(x_i=self.x_i, y_i=self.y_i, h_i=self.h_i,
d_i=self.windFarmModel.windTurbines.diameter(self.type_i))
else:
plane = (None,)
if wd is None:
wd = self.wd
else:
assert np.all(np.isin(wd, self.wd)), "All wd=%s not in simulation result" % wd
if ws is None:
ws = self.ws
else:
assert np.all(np.isin(ws, self.ws)), "All ws=%s not in simulation result (ws=%s)" % (ws, self.ws)
wd, ws = np.atleast_1d(wd), np.atleast_1d(ws)
l_indices = np.argwhere(wd[:, None] == self.wd)[:, 1]
k_indices = np.argwhere(ws[:, None] == self.ws)[:, 1]
X, Y, x_j, y_j, h_j = grid
lw_j, WS_eff_jlk, TI_eff_jlk = self.windFarmModel._flow_map(
x_j, y_j, h_j,
self.x_i, self.y_i, self.h_i, self.type_i, self.yaw_ilk,
self.localWind.WD_ilk[:, l_indices][:, :, k_indices],
self.localWind.WS_ilk[:, l_indices][:, :, k_indices],
self.localWind.TI_ilk[:, l_indices][:, :, k_indices],
self.WS_eff_ilk[:, l_indices][:, :, k_indices],
self.TI_eff_ilk[:, l_indices][:, :, k_indices],
self.ct_ilk[:, l_indices][:, :, k_indices],
wd, ws)
if self.yaw_ilk is not None:
yaw_ilk = self.yaw_ilk[:, l_indices][:, :, k_indices]
else:
yaw_ilk = None
return FlowMap(self, X, Y, lw_j, WS_eff_jlk, TI_eff_jlk, wd, ws,
yaw_ilk=yaw_ilk, plane=plane)
def main():
if __name__ == '__main__':
from py_wake.examples.data.iea37 import IEA37Site, IEA37_WindTurbines
from py_wake import IEA37SimpleBastankhahGaussian
import matplotlib.pyplot as plt
site = IEA37Site(16)
x, y = site.initial_position.T
windTurbines = IEA37_WindTurbines()
# NOJ wake model
wind_farm_model = IEA37SimpleBastankhahGaussian(site, windTurbines)
simulation_result = wind_farm_model(x, y)
fm = simulation_result.flow_map(wd=30)
fm.plot_wake_map()
plt.figure()
fm.plot(fm.power_xylk()[:, :, 0, 0] * 1e-3, "Power [kW]")
fm = simulation_result.flow_map(grid=HorizontalGrid(resolution=50))
plt.figure()
fm.plot(fm.aep_xy(), "AEP [GWh]")
plt.show()
main()