Borders, Obstacles & Buffering¶
OptiWindNet models site bounds with an exterior border (allowed area) and interior obstacles (exclusion zones), and keeps electrical network design compliant with the bounds. This notebook walks from initialization and optimization under constraints, through cleaning and buffering the geometry, to validating turbine/substation placement. We will explore following features (methods):
Optimize under bounds:
.optimize(): optimize electrical network while enforcing border/obstacle constraints.Merge & clean boundary:
.merge_obstacles_into_border(): resolve intersections/touching constraints, absorb irrelevant obstacles, and simplify the exterior boundary.Buffer geometry:
.add_buffer(buffer_dist=...): expand the border and shrink obstacles to add safety margins; might smooth concavities or remove obstacles depending onbuffer_dist.Compare originals vs buffered:
.plot_original_vs_buffered(): overlay plot of border/obstacles before and after buffering to inspect how buffering changed shapes.Validate placement:
.optimize()raises aValueErrorif any turbine or substation lies outside the border or inside an obstacle.
Import required packages
[1]:
from optiwindnet.api import WindFarmNetwork
import numpy as np
import matplotlib.pyplot as plt
[2]:
# Display figures as SVG in Jupyter notebooks
%config InlineBackend.figure_formats = ['svg']
Borders and obstacles¶
1. Initialize¶
Create a WindFarmNetwork instances from an `osm.pbf´ file and optimize it.
[3]:
wfn1 = WindFarmNetwork.from_pbf(filepath='data/DTU_letters.osm.pbf', cables=7)
Plot the location geometry and the optimized network to confirm that the borders and obstacles are properly initialized and considered for optimization.
[4]:
wfn1
[4]:
[5]:
wfn1.L.graph['T']
[5]:
40
[6]:
res_optimize = wfn1.optimize()
wfn1
[6]:
Note: OptiWindNet works properly without borders/obstacles also.
2. Obstacles intersecting with the exterior borders¶
Let’s create an instance of WindFarmNetwork directly via coordinates to have full control over border/obstacle definition.
[7]:
turbinesC = np.array([
[ 316976, 6175410],
[ 316998, 6175380],
[ 316965, 6175368],
[ 316997, 6175347],
[ 316967 , 6175314],
[ 317009 , 6175267],
[ 317044, 6175282],
[ 316994 , 6175296],
[ 317065, 6175335],
[ 317030, 6175318],
[ 317029 , 6175366],
[ 317026, 6175401],
[ 317057, 6175379],
[ 317085, 6175354],
[ 317068, 6175406],
[ 317144, 6175403],
[ 317115, 6175342],
[ 317091, 6175320],
[ 317240, 6175259],
[ 317111 , 6175293],
[ 317126, 6175262],
[ 317152, 6175320],
[ 317102, 6175385],
[ 317179, 6175383],
[ 317143, 6175367],
[ 317223, 6175399],
[ 317222, 6175358],
[ 317185, 6175347],
[ 317208, 6175323],
[ 317188, 6175299],
[ 317205, 6175270],
[ 317231, 6175296],
[ 317272, 6175287],
[ 317244, 6175340],
[ 317283, 6175321],
[ 317285, 6175360],
[ 316960, 6175270],
[ 317253, 6175380],
[ 317287, 6175397],
[ 317152, 6175286],
])
borderC = np.array([
[316956, 6175267],
[317022, 6175265],
[317043, 6175275],
[317059 , 6175295],
[317068, 6175322],
[317069, 6175349],
[317090, 6175348],
[317086, 6175262],
[317153, 6175259],
[317157, 6175346],
[317178 , 6175345],
[317177, 6175316],
[317184, 6175289],
[317199, 6175268],
[317218, 6175256],
[317240, 6175256],
[317260, 6175266],
[317276, 6175286],
[317285, 6175312],
[317289, 6175399],
[317242, 6175401],
[317239, 6175319],
[317238, 6175312],
[317235, 6175308],
[317232, 6175305],
[317229, 6175305],
[317226, 6175308],
[317224, 6175313],
[317223, 6175319],
[317227, 6175402],
[316963, 6175413],
])
obstaclesC_ = [
np.array([
[316998, 6175301],
[317001 , 6175376],
[317013, 6175375],
[317021, 6175369],
[317026, 6175359],
[317029, 6175345],
[317029, 6175330],
[317025, 6175316],
[317019, 6175306],
[317011, 6175301],
]),
np.array([
[316920, 6175300],
[316920, 6175400],
[316950, 6175400],
[316950, 6175300],
]),
np.array([
[317100, 6175450],
[317100, 6175400],
[317080, 6175400],
[317080, 6175450],
]),
]
substationsC = np.array([
[317167 , 6175351]])
[8]:
wfn2 = WindFarmNetwork(turbinesC=turbinesC, substationsC=substationsC, borderC=borderC, obstacleC_=obstaclesC_, cables=7)
wfn2
[8]:
[9]:
res_optimize = wfn2.optimize()
wfn2
[9]:
We can use .merge_obstacles_into_border() to refine the borders, simplify the boundary constraints and remove irrelevant obstacles.
[10]:
wfn2.merge_obstacles_into_border()
res_optimize = wfn2.optimize()
wfn2
Obstacle at index 1 is completely outside the border and is neglected.
Obstacle at index 2 intersects with the exteriour border and is merged into the exterior border.
[10]:
Buffering¶
After initializing the WindFarmNetwork, a buffer can be applied to borders and obstacles via the .add_buffer() method. The exterior border will be expanded, while interior obstacles will be shrunk accordingly.
Initialize WindFarmNetwork instance
[11]:
wfn3 = WindFarmNetwork.from_pbf(filepath='data/DTU_letters.osm.pbf', cables=7)
res_optimize = wfn3.optimize()
wfn3
[11]:
apply buffering to wfn3.
[12]:
wfn3.add_buffer(buffer_dist=5)
res_optimize = wfn3.optimize()
wfn3
The defined border is non-convex and buffering may introduce unexpected changes. For visual comparison use plot_original_vs_buffered().
[12]:
Original vs buffered border/obstacles can be visualized using plot_original_vs_buffered()
[13]:
wfn3.plot_original_vs_buffered();
Removal of a concavity¶
In this case a message is printed out, providing information about the potential changes in the border.
[14]:
wfn4 = WindFarmNetwork.from_pbf(filepath='data/DTU_letters.osm.pbf', cables=7)
wfn4.add_buffer(buffer_dist=10)
The defined border is non-convex and buffering may introduce unexpected changes. For visual comparison use plot_original_vs_buffered().
Plotting original vs buffered borders confirms that one of the concavities is removed after buffering.
[15]:
wfn4.plot_original_vs_buffered();
Optimize
The optimized network might change and use new routes after buffering.
[16]:
res_optimize = wfn4.optimize()
wfn4
[16]:
Removal of an obstacle¶
[17]:
wfn5 = WindFarmNetwork.from_pbf(filepath='data/DTU_letters.osm.pbf', cables=7)
wfn5.add_buffer(buffer_dist=15)
The defined border is non-convex and buffering may introduce unexpected changes. For visual comparison use plot_original_vs_buffered().
Buffering by 15.00 completely removed the obstacle at index 0. For visual comparison use plot_original_vs_buffered().
Plotting original vs buffered borders confirms that obstacle (inside D letter) is removed after buffering.
[18]:
wfn5.plot_original_vs_buffered();
Optimize
The optimized network might change and use new routes after buffering.
[19]:
wfn5.optimize()
wfn5
[19]:
Turbines outside the border or inside the obstacles¶
When wfn.optimize() is called, it first checks if the all turbines are within the allowed area and not inside any exclusion zone. A ValueError exception is raised if this is not the case.
[20]:
turbinesC = np.array([
[0, 0],
[ 316976, 6175410],
[ 316998, 6175380],
])
borderC = np.array([
[316956, 6175267],
[317022, 6175265],
[317043, 6175275],
[317059 , 6175295],
[317068, 6175322],
[317069, 6175349],
[317090, 6175348],
[317086, 6175262],
[317153, 6175259],
[317157, 6175346],
[317178 , 6175345],
[317177, 6175316],
[317184, 6175289],
[317199, 6175268],
[317218, 6175256],
[317240, 6175256],
[317260, 6175266],
[317276, 6175286],
[317285, 6175312],
[317289, 6175399],
[317242, 6175401],
[317239, 6175319],
[317238, 6175312],
[317235, 6175308],
[317232, 6175305],
[317229, 6175305],
[317226, 6175308],
[317224, 6175313],
[317223, 6175319],
[317227, 6175402],
[316963, 6175413],
])
substationsC = np.array([
[317167 , 6175351]])
[21]:
wfn6 = WindFarmNetwork(
turbinesC=turbinesC,
substationsC=substationsC,
borderC=borderC,
obstacleC_=obstaclesC_,
cables=7,
)
[22]:
wfn6.optimize()
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
Cell In[23], line 1
----> 1 wfn6.optimize()
File ~/docs/git/OptiWindNet.git/build/__editable__.optiwindnet-0.2.2.dev82+g4d9174546-py3-none-any/optiwindnet/api.py:602, in WindFarmNetwork.optimize(self, turbinesC, substationsC, router, verbose)
598 else:
599 warmstart = {}
601 self._S, self._G = router.route(
--> 602 P=self.P,
603 A=self.A,
604 cables=self.cables,
605 cables_capacity=self.cables_capacity,
606 verbose=verbose,
607 **warmstart,
608 )
609 self._is_stale_SG = False
611 terse_links = self.terse_links()
File ~/docs/git/OptiWindNet.git/build/__editable__.optiwindnet-0.2.2.dev82+g4d9174546-py3-none-any/optiwindnet/api.py:267, in WindFarmNetwork.P(self)
265 "Triangular mesh over `L` (navigation mesh)."
266 if self._is_stale_PA:
--> 267 self._refresh_planar()
268 return self._P
File ~/docs/git/OptiWindNet.git/build/__editable__.optiwindnet-0.2.2.dev82+g4d9174546-py3-none-any/optiwindnet/api.py:226, in WindFarmNetwork._refresh_planar(self)
222 out_of_bounds -= obstacle.exterior
223 if not out_of_bounds.is_empty:
224 # TODO: if relevant, get coordinates of turbines from out_of_bounds
225 # print(list(out_of_bounds.geoms))
--> 226 raise ValueError('Turbine out of bounds!')
227 self._P, self._A = make_planar_embedding(self._L)
228 self._is_stale_PA = False
ValueError: Turbine out of bounds!