add single axis tracker tests

Author: wholmgren

pvlib/test/test_tracking.py

@@ -0,0 +1,154 @@
+import logging
+pvl_logger = logging.getLogger('pvlib')
+
+import datetime
+
+import numpy as np
+import pandas as pd
+
+from nose.tools import raises, assert_almost_equals
+from nose.plugins.skip import SkipTest
+from pandas.util.testing import assert_frame_equal
+
+from pvlib.location import Location
+from pvlib import solarposition
+from pvlib import tracking
+
+
+def test_solar_noon():
+    apparent_zenith = pd.Series([10])
+    apparent_azimuth = pd.Series([180])
+    tracker_data = tracking.singleaxis(apparent_zenith, apparent_azimuth,
+                                       axis_tilt=0, axis_azimuth=0,
+                                       max_angle=90, backtrack=True, 
+                                       gcr=2.0/7.0)
+    
+    expect = pd.DataFrame({'aoi': 10, 'surface_azimuth': np.nan,
+                           'surface_tilt': 90, 'tracker_theta': 0},
+                           index=[0], dtype=np.float64)
+    
+    assert_frame_equal(expect, tracker_data)
+
+
+def test_azimuth_north_south():
+    apparent_zenith = pd.Series([60])
+    apparent_azimuth = pd.Series([90])
+
+    tracker_data = tracking.singleaxis(apparent_zenith, apparent_azimuth,
+                                       axis_tilt=0, axis_azimuth=180,
+                                       max_angle=90, backtrack=True, 
+                                       gcr=2.0/7.0)
+    
+    expect = pd.DataFrame({'aoi': 0, 'surface_azimuth': 90,
+                           'surface_tilt': 30, 'tracker_theta': -60},
+                           index=[0], dtype=np.float64)
+                           
+    assert_frame_equal(expect, tracker_data)
+    
+    tracker_data = tracking.singleaxis(apparent_zenith, apparent_azimuth,
+                                       axis_tilt=0, axis_azimuth=0,
+                                       max_angle=90, backtrack=True, 
+                                       gcr=2.0/7.0)
+    
+    expect['tracker_theta'] *= -1
+                           
+    assert_frame_equal(expect, tracker_data)
+
+
+def test_max_angle():
+    apparent_zenith = pd.Series([60])
+    apparent_azimuth = pd.Series([90])
+    tracker_data = tracking.singleaxis(apparent_zenith, apparent_azimuth,
+                                       axis_tilt=0, axis_azimuth=0,
+                                       max_angle=45, backtrack=True, 
+                                       gcr=2.0/7.0)
+    
+    expect = pd.DataFrame({'aoi': 15, 'surface_azimuth': 90,
+                           'surface_tilt': 45, 'tracker_theta': 45},
+                           index=[0], dtype=np.float64)
+    
+    assert_frame_equal(expect, tracker_data)
+
+
+def test_backtrack():
+    apparent_zenith = pd.Series([80])
+    apparent_azimuth = pd.Series([90])
+
+    tracker_data = tracking.singleaxis(apparent_zenith, apparent_azimuth,
+                                       axis_tilt=0, axis_azimuth=0,
+                                       max_angle=90, backtrack=False, 
+                                       gcr=2.0/7.0)
+    
+    expect = pd.DataFrame({'aoi': 0, 'surface_azimuth': 90,
+                           'surface_tilt': 10, 'tracker_theta': 80},
+                           index=[0], dtype=np.float64)
+    
+    assert_frame_equal(expect, tracker_data)
+    
+    tracker_data = tracking.singleaxis(apparent_zenith, apparent_azimuth,
+                                       axis_tilt=0, axis_azimuth=0,
+                                       max_angle=90, backtrack=True, 
+                                       gcr=2.0/7.0)
+    
+    expect = pd.DataFrame({'aoi': 52.5716, 'surface_azimuth': 90,
+                           'surface_tilt': 62.5716, 'tracker_theta': 27.4283},
+                           index=[0], dtype=np.float64)
+    
+    assert_frame_equal(expect, tracker_data)
+
+
+def test_axis_tilt():
+    apparent_zenith = pd.Series([30])
+    apparent_azimuth = pd.Series([135])
+
+    tracker_data = tracking.singleaxis(apparent_zenith, apparent_azimuth,
+                                       axis_tilt=30, axis_azimuth=180,
+                                       max_angle=90, backtrack=True, 
+                                       gcr=2.0/7.0)
+    
+    expect = pd.DataFrame({'aoi': 7.286245, 'surface_azimuth': 142.6573,
+                           'surface_tilt': 54.0125, 'tracker_theta': -20.88121},
+                           index=[0], dtype=np.float64)
+    
+    assert_frame_equal(expect, tracker_data)
+    
+    tracker_data = tracking.singleaxis(apparent_zenith, apparent_azimuth,
+                                       axis_tilt=30, axis_azimuth=0,
+                                       max_angle=90, backtrack=True, 
+                                       gcr=2.0/7.0)
+    
+    expect = pd.DataFrame({'aoi': 47.6632, 'surface_azimuth': 50.9696,
+                           'surface_tilt': 47.4847, 'tracker_theta': 31.6655},
+                           index=[0], dtype=np.float64)
+    
+    assert_frame_equal(expect, tracker_data)
+
+
+def test_axis_azimuth():
+    apparent_zenith = pd.Series([30])
+    apparent_azimuth = pd.Series([90])
+
+    tracker_data = tracking.singleaxis(apparent_zenith, apparent_azimuth,
+                                       axis_tilt=0, axis_azimuth=90,
+                                       max_angle=90, backtrack=True, 
+                                       gcr=2.0/7.0)
+    
+    expect = pd.DataFrame({'aoi': 30, 'surface_azimuth': np.nan,
+                           'surface_tilt': 90, 'tracker_theta': 0},
+                           index=[0], dtype=np.float64)
+    
+    assert_frame_equal(expect, tracker_data)
+    
+    apparent_zenith = pd.Series([30])
+    apparent_azimuth = pd.Series([180])
+    
+    tracker_data = tracking.singleaxis(apparent_zenith, apparent_azimuth,
+                                       axis_tilt=0, axis_azimuth=90,
+                                       max_angle=90, backtrack=True, 
+                                       gcr=2.0/7.0)
+    
+    expect = pd.DataFrame({'aoi': 0, 'surface_azimuth': 0,
+                           'surface_tilt': 60, 'tracker_theta': 30},
+                           index=[0], dtype=np.float64)
+    
+    assert_frame_equal(expect, tracker_data)