Add desoto and pvsyst as dc_model options to ModelChain

docs/sphinx/source/api.rst

@@ -204,10 +204,10 @@ AOI modifiers
    pvsystem.ashraeiam
    pvsystem.sapm_aoi_loss
 
-Single diode model
-------------------
+Single diode models
+-------------------
 
-Functions relevant for the single diode model.
+Functions relevant for single diode models.
 
 .. autosummary::
    :toctree: generated/
@@ -419,7 +419,8 @@ ModelChain model definitions.
    :toctree: generated/
 
    modelchain.ModelChain.sapm
-   modelchain.ModelChain.singlediode
+   modelchain.ModelChain.desoto
+   modelchain.ModelChain.pvsyst
    modelchain.ModelChain.pvwatts_dc
    modelchain.ModelChain.snlinverter
    modelchain.ModelChain.adrinverter

docs/sphinx/source/whatsnew/v0.6.0.rst

@@ -53,6 +53,8 @@ API Changes
   dirindex functions. (:issue:`311`, :issue:`396`)
 * Method ModelChain.infer_dc_model now returns a tuple (function handle, model name string)
   instead of only the function handle (:issue:`417`)
+* Add DC model methods desoto and pvsyst to ModelChain, and deprecates DC model method singlediode
+  (singlediode defaults to desoto until v0.7.0) (:issue:`487`)
 
 
 Enhancements
@@ -104,6 +106,7 @@ Enhancements
 * Add irradiance.clearness_index function. (:issue:`396`)
 * Add irradiance.clearness_index_zenith_independent function. (:issue:`396`)
 * Add checking for consistency between module_parameters and dc_model. (:issue:`417`)
+* Add DC model methods desoto and pvsyst to ModelChain (:issue:`487`)
 
 
 Bug fixes

pvlib/modelchain.py

@@ -14,6 +14,7 @@
 from pvlib.tracking import SingleAxisTracker
 import pvlib.irradiance  # avoid name conflict with full import
 from pvlib.pvsystem import DC_MODEL_PARAMS
+from pvlib._deprecation import pvlibDeprecationWarning
 
 
 def basic_chain(times, latitude, longitude,
@@ -251,8 +252,8 @@ class ModelChain(object):
     dc_model: None, str, or function, default None
         If None, the model will be inferred from the contents of
         system.module_parameters. Valid strings are 'sapm',
-        'singlediode', 'pvwatts'. The ModelChain instance will be passed
-        as the first argument to a user-defined function.
+        'desoto', 'pvsyst', 'pvwatts'. The ModelChain instance will
+        be passed as the first argument to a user-defined function.
 
     ac_model: None, str, or function, default None
         If None, the model will be inferred from the contents of
@@ -379,10 +380,19 @@ def dc_model(self, model):
                                          str(missing_params))
                 if model == 'sapm':
                     self._dc_model = self.sapm
-                elif model == 'singlediode':
-                    self._dc_model = self.singlediode
+                elif model == 'desoto':
+                    self._dc_model = self.desoto
+                elif model == 'pvsyst':
+                    self._dc_model = self.pvsyst
                 elif model == 'pvwatts':
                     self._dc_model = self.pvwatts_dc
+                elif model == 'singlediode':
+                    warnings.warn('DC model keyword singlediode used for '
+                                  'ModelChain object. singlediode is '
+                                  'ambiguous, use desoto instead. singlediode '
+                                  'keyword will be removed in v0.7.0 and '
+                                  'later', pvlibDeprecationWarning)
+                    self._dc_model = self.desoto
             else:
                 raise ValueError(model + ' is not a valid DC power model')
         else:
@@ -393,7 +403,10 @@ def infer_dc_model(self):
         if set(['A0', 'A1', 'C7']) <= params:
             return self.sapm, 'sapm'
         elif set(['a_ref', 'I_L_ref', 'I_o_ref', 'R_sh_ref', 'R_s']) <= params:
-            return self.singlediode, 'singlediode'
+            return self.desoto, 'desoto'
+        elif set(['gamma_ref', 'mu_gamma', 'I_L_ref', 'I_o_ref',
+                  'R_sh_ref', 'R_sh_0', 'R_sh_exp', 'R_s']) <= params:
+            return self.pvsyst, 'pvsyst'
         elif set(['pdc0', 'gamma_pdc']) <= params:
             return self.pvwatts_dc, 'pvwatts'
         else:
@@ -408,7 +421,44 @@ def sapm(self):
 
         return self
 
+    def desoto(self):
+        (photocurrent, saturation_current, resistance_series,
+         resistance_shunt, nNsVth) = (
+            self.system.calcparams_desoto(self.effective_irradiance,
+                                          self.temps['temp_cell']))
+
+        self.diode_params = (photocurrent, saturation_current,
+                             resistance_series,
+                             resistance_shunt, nNsVth)
+
+        self.dc = self.system.singlediode(
+            photocurrent, saturation_current, resistance_series,
+            resistance_shunt, nNsVth)
+
+        self.dc = self.system.scale_voltage_current_power(self.dc).fillna(0)
+
+        return self
+
+    def pvsyst(self):
+        (photocurrent, saturation_current, resistance_series,
+         resistance_shunt, nNsVth) = (
+            self.system.calcparams_pvsyst(self.effective_irradiance,
+                                          self.temps['temp_cell']))
+
+        self.diode_params = (photocurrent, saturation_current,
+                             resistance_series,
+                             resistance_shunt, nNsVth)
+
+        self.dc = self.system.singlediode(
+            photocurrent, saturation_current, resistance_series,
+            resistance_shunt, nNsVth)
+
+        self.dc = self.system.scale_voltage_current_power(self.dc).fillna(0)
+
+        return self
+
     def singlediode(self):
+        """Deprecated"""
         (photocurrent, saturation_current, resistance_series,
          resistance_shunt, nNsVth) = (
             self.system.calcparams_desoto(self.effective_irradiance,

pvlib/pvsystem.py

@@ -31,6 +31,13 @@
                           'C7', 'Isco', 'Impo', 'Aisc', 'Aimp', 'Bvoco',
                           'Mbvoc', 'Bvmpo', 'Mbvmp', 'N', 'Cells_in_Series',
                           'IXO', 'IXXO', 'FD']),
+                   'desoto' :
+                     set(['alpha_sc', 'a_ref', 'I_L_ref', 'I_o_ref',
+                          'R_sh_ref', 'R_s']),
+                   'pvsyst' :
+                     set(['gamma_ref', 'mu_gamma', 'I_L_ref', 'I_o_ref',
+                          'R_sh_ref', 'R_sh_0', 'R_s', 'alpha_sc', 'EgRef',
+                          'cells_in_series']),
                    'singlediode' :
                      set(['alpha_sc', 'a_ref', 'I_L_ref', 'I_o_ref',
                           'R_sh_ref', 'R_s']),

pvlib/test/test_modelchain.py

@@ -14,12 +14,13 @@
 from pvlib.pvsystem import PVSystem
 from pvlib.tracking import SingleAxisTracker
 from pvlib.location import Location
+from pvlib._deprecation import pvlibDeprecationWarning
 
 from pandas.util.testing import assert_series_equal, assert_frame_equal
 import pytest
 
-from test_pvsystem import sam_data
-from conftest import requires_scipy
+from test_pvsystem import sam_data, pvsyst_module_params
+from conftest import fail_on_pvlib_version, requires_scipy
 
 
 @pytest.fixture
@@ -53,6 +54,20 @@ def cec_dc_snl_ac_system(sam_data):
     return system
 
 
+@pytest.fixture
+def pvsyst_dc_snl_ac_system(sam_data):
+    module = 'PVsyst test module'
+    module_parameters = pvsyst_module_params()
+    module_parameters['b'] = 0.05
+    inverters = sam_data['cecinverter']
+    inverter = inverters['ABB__MICRO_0_25_I_OUTD_US_208_208V__CEC_2014_'].copy()
+    system = PVSystem(surface_tilt=32.2, surface_azimuth=180,
+                      module=module,
+                      module_parameters=module_parameters,
+                      inverter_parameters=inverter)
+    return system
+
+
 @pytest.fixture
 def cec_dc_adr_ac_system(sam_data):
     modules = sam_data['cecmod']
@@ -203,14 +218,26 @@ def poadc(mc):
 
 
 @pytest.mark.parametrize('dc_model', [
-    'sapm', pytest.param('singlediode', marks=requires_scipy), 'pvwatts_dc'])
-def test_infer_dc_model(system, cec_dc_snl_ac_system,
+    'sapm',
+    pytest.param('desoto', marks=requires_scipy), 
+    pytest.param('pvsyst', marks=requires_scipy), 
+    pytest.param('singlediode', marks=requires_scipy), 
+    'pvwatts_dc'])
+def test_infer_dc_model(system, cec_dc_snl_ac_system, pvsyst_dc_snl_ac_system,
                         pvwatts_dc_pvwatts_ac_system, location, dc_model,
                         weather, mocker):
-    dc_systems = {'sapm': system, 'singlediode': cec_dc_snl_ac_system,
+    dc_systems = {'sapm': system,
+                  'desoto': cec_dc_snl_ac_system,
+                  'pvsyst': pvsyst_dc_snl_ac_system,
+                  'singlediode': cec_dc_snl_ac_system,
                   'pvwatts_dc': pvwatts_dc_pvwatts_ac_system}
+    dc_model_function = {'sapm': 'sapm',
+                         'desoto': 'calcparams_desoto',
+                         'pvsyst': 'calcparams_pvsyst',
+                         'singlediode': 'calcparams_desoto',
+                         'pvwatts_dc': 'pvwatts_dc'}
     system = dc_systems[dc_model]
-    m = mocker.spy(system, dc_model)
+    m = mocker.spy(system, dc_model_function[dc_model])
     mc = ModelChain(system, location,
                     aoi_model='no_loss', spectral_model='no_loss')
     mc.run_model(weather.index, weather=weather)
@@ -410,6 +437,14 @@ def test_bad_get_orientation():
         modelchain.get_orientation('bad value')
 
 
+@fail_on_pvlib_version('0.7')
+def test_deprecated_07():
+    with pytest.warns(pvlibDeprecationWarning):
+        mc = ModelChain(cec_dc_snl_ac_system, location,
+                        dc_model='singlediode', # this should fail after 0.7
+                        aoi_model='no_loss', spectral_model='no_loss')
+
+
 @requires_scipy
 def test_basic_chain_required(sam_data):
     times = pd.DatetimeIndex(start='20160101 1200-0700',