Create inverter.py (pvlib#886)

* create inverter.py, move code, add adrinverter fixture

* stickler, adjust PVSystem methods

* update modelchain, test fixes

* sticker

* docstring improvements

* more docstring work

* lint, kludge inverter.test_deprecated_09

* lint, kludge test_deprecated_09 x2

* use new conftest capability

* correct use of fixture

* add test for invalid ac model string

* update whatsnew

* update api.rst

* extend test_ac_models to new key values

* more for whatsnew

* correct modelchain.ac_model test

* test correction

* edits from review

* more edits from review

* fix thedocs, error

* fix indents

* improvements from review

* more improvements from review

* improvements from review

* improvements from review

* last cleanup

* last cleanup part 2

* last cleanup part 3

* py:attribute in whatsnew

* docstring improvements

* one more

Author: cwhanse

docs/sphinx/source/api.rst

@@ -265,10 +265,21 @@ Low-level functions for solving the single diode equation.
    singlediode.bishop88_v_from_i
    singlediode.bishop88_mpp
 
-SAPM model
-----------
+Inverter models (DC to AC conversion)
+-------------------------------------
+
+.. autosummary::
+   :toctree: generated/
+
+   inverter.sandia
+   inverter.adr
+   inverter.pvwatts
 
-Functions relevant for the SAPM model.
+PV System Models
+----------------
+
+Sandia array performance model (SAPM)
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 .. autosummary::
    :toctree: generated/
@@ -277,28 +288,27 @@ Functions relevant for the SAPM model.
    pvsystem.sapm_effective_irradiance
    pvsystem.sapm_spectral_loss
    pvsystem.sapm_aoi_loss
-   pvsystem.snlinverter
-   pvsystem.adrinverter
+   inverter.sandia
    temperature.sapm_cell
 
 Pvsyst model
--------------
-
-Functions relevant for the Pvsyst model.
+^^^^^^^^^^^^
 
 .. autosummary::
    :toctree: generated/
 
    temperature.pvsyst_cell
+   pvsystem.calcparams_pvsyst
+   pvsystem.singlediode
 
 PVWatts model
--------------
+^^^^^^^^^^^^^
 
 .. autosummary::
    :toctree: generated/
 
    pvsystem.pvwatts_dc
-   pvsystem.pvwatts_ac
+   inverter.pvwatts
    pvsystem.pvwatts_losses
 
 Functions for fitting diode models

docs/sphinx/source/introtutorial.rst

@@ -96,7 +96,7 @@ to accomplish our system modeling goal:
             total_irrad['poa_direct'], total_irrad['poa_diffuse'],
             am_abs, aoi, module)
         dc = pvlib.pvsystem.sapm(effective_irradiance, tcell, module)
-        ac = pvlib.pvsystem.snlinverter(dc['v_mp'], dc['p_mp'], inverter)
+        ac = pvlib.inverter.sandia(dc['v_mp'], dc['p_mp'], inverter)
         annual_energy = ac.sum()
         energies[name] = annual_energy
 

docs/sphinx/source/whatsnew/v0.8.0.rst

@@ -3,15 +3,25 @@
 v0.8.0 (Month day, year)
 -------------------------
 
+API Changes with Deprecations
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+* Moved functions related to inverters from ``pvsystem.py`` to ``inverter.py``.
+  Functions are renamed to follow a more consistent pattern, as follows (:pull:`886`):
+   - :py:func:`pvlib.pvsystem.snlinverter` is now :py:func:`pvlib.inverter.sandia`
+   - :py:func:`pvlib.pvsystem.pvwatts_ac` is now :py:func:`pvlib.inverter.pvwatts`
+   - :py:func:`pvlib.pvsystem.adrinverter` is now :py:func:`pvlib.inverter.adr`
+* Argument ``ac_model`` for :py:class:`pvlib.modelchain.ModelChain` now accepts
+  ``'sandia'``, ``'pvwatts'`` and ``'adr'`` for the inverter models.  (:pull:`886`)
+
 API Changes
 ~~~~~~~~~~~
-* Removed ``run_parallel_calculations`` and ``n_workers_for_parallel_calcs`` 
+* Removed ``run_parallel_calculations`` and ``n_workers_for_parallel_calcs``
   from :py:func:`pvlib.bifacial.pvfactors_timeseries` inputs (:issue:`902`)(:pull:`934`)
 
 Enhancements
 ~~~~~~~~~~~~
 * Update :func:`~pvlib.bifacial.pvfactors_timeseries` to run with ``pvfactors`` v1.4.1 (:issue:`902`)(:pull:`934`)
-* Add :py:func:`pvlib.iam.marion_diffuse` and 
+* Add :py:func:`pvlib.iam.marion_diffuse` and
   :py:func:`pvlib.iam.marion_integrate` to calculate IAM values for
   diffuse irradiance. (:pull:`984`)
 
@@ -23,6 +33,8 @@ Testing
 ~~~~~~~
 * Decorator :py:func:`pvlib.conftest.fail_on_pvlib_version` can now be
   applied to functions that require args or kwargs. (:pull:`973`)
+* Test added for :py:class:`pvlib.modelchain.ModelChain` to confirm ValueError when
+  ``ac_model`` is an invalid string. (:pull:`886`)
 
 Documentation
 ~~~~~~~~~~~~~
@@ -32,6 +44,8 @@ Documentation
 * Clarify units for heat loss factors in
   :py:func:`pvlib.temperature.pvsyst_cell` and
   :py:func:`pvlib.temperature.faiman`. (:pull:`960`)
+* Corrected key names for :py:func:`pvlib.inverter.sandia`. (:issue:`976`,
+  :pull:`886`)
 * Add a transposition gain example to the gallery.  (:pull:`979`)
 * Add a gallery example of calculating diffuse IAM using
   :py:func:`pvlib.iam.marion_diffuse`. (:pull:`984`)

docs/tutorials/forecast.ipynb

@@ -8159,7 +8159,7 @@
        "  solar_position_method: nrel_numpy\n",
        "  airmass_model: kastenyoung1989\n",
        "  dc_model: sapm\n",
-       "  ac_model: snlinverter\n",
+       "  ac_model: sandia\n",
        "  aoi_model: sapm_aoi_loss\n",
        "  spectral_model: sapm_spectral_loss\n",
        "  temp_model: sapm_temp\n",

docs/tutorials/forecast_to_power.ipynb

@@ -67,7 +67,7 @@
     "import matplotlib as mpl\n",
     "\n",
     "# finally, we import the pvlib library\n",
-    "from pvlib import solarposition,irradiance,atmosphere,pvsystem\n",
+    "from pvlib import solarposition, irradiance, atmosphere, pvsystem, inverter\n",
     "from pvlib.forecast import GFS, NAM, NDFD, RAP, HRRR"
    ]
   },
@@ -876,7 +876,7 @@
     }
    ],
    "source": [
-    "p_ac = pvsystem.snlinverter(sapm_out.v_mp, sapm_out.p_mp, sapm_inverter)\n",
+    "p_ac = inverter.sandia(sapm_out.v_mp, sapm_out.p_mp, sapm_inverter)\n",
     "\n",
     "p_ac.plot()\n",
     "plt.ylabel('AC Power (W)')\n",

docs/tutorials/pvsystem.ipynb

@@ -16,7 +16,7 @@
     "1. [systemdef](#systemdef)\n",
     "2. [Angle of Incidence Modifiers](#Angle-of-Incidence-Modifiers)\n",
     "2. [Sandia Cell Temp correction](#Sandia-Cell-Temp-correction)\n",
-    "2. [Sandia Inverter Model](#snlinverter)\n",
+    "2. [Sandia Inverter Model](#Sandia-inverter-model)\n",
     "2. [Sandia Array Performance Model](#SAPM)\n",
     "    1. [SAPM IV curves](#SAPM-IV-curves)\n",
     "2. [DeSoto Model](#desoto)\n",
@@ -78,7 +78,7 @@
    "outputs": [],
    "source": [
     "import pvlib\n",
-    "from pvlib import pvsystem"
+    "from pvlib import pvsystem, inverter"
    ]
   },
   {
@@ -573,7 +573,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "### snlinverter"
+    "### Sandia-inverter-model"
    ]
   },
   {
@@ -1356,7 +1356,7 @@
     "idcs = pd.Series(np.linspace(0,11,110))\n",
     "pdcs = idcs * vdcs\n",
     "\n",
-    "pacs = pvsystem.snlinverter(vdcs, pdcs, inverters['ABB__MICRO_0_25_I_OUTD_US_208_208V__CEC_2014_'])\n",
+    "pacs = inverter.sandia(vdcs, pdcs, inverters['ABB__MICRO_0_25_I_OUTD_US_208_208V__CEC_2014_'])\n",
     "#pacs.plot()\n",
     "plt.plot(pacs, pdcs)\n",
     "plt.ylabel('ac power')\n",

docs/tutorials/tmy_to_power.ipynb

@@ -1184,8 +1184,8 @@
    ],
    "source": [
     "p_acs = pd.DataFrame()\n",
-    "p_acs['sapm'] = pvlib.pvsystem.snlinverter(sapm_out.v_mp, sapm_out.p_mp, sapm_inverter)\n",
-    "p_acs['sd'] = pvlib.pvsystem.snlinverter(single_diode_out.v_mp, single_diode_out.p_mp, sapm_inverter)\n",
+    "p_acs['sapm'] = pvlib.inverter.sandia(sapm_out.v_mp, sapm_out.p_mp, sapm_inverter)\n",
+    "p_acs['sd'] = pvlib.inverter.sandia(single_diode_out.v_mp, single_diode_out.p_mp, sapm_inverter)\n",
     "\n",
     "p_acs.plot()\n",
     "plt.ylabel('AC Power (W)')"