def test_newton_fs_495(method, cec_module_fs_495):
"""test pvsystem.singlediode with different methods on FS495"""
fs_495 = cec_module_fs_495
x = pvsystem.calcparams_desoto(
effective_irradiance=POA, temp_cell=TCELL,
alpha_sc=fs_495['alpha_sc'], a_ref=fs_495['a_ref'],
I_L_ref=fs_495['I_L_ref'], I_o_ref=fs_495['I_o_ref'],
R_sh_ref=fs_495['R_sh_ref'], R_s=fs_495['R_s'],
EgRef=1.475, dEgdT=-0.0003)
il, io, rs, rsh, nnsvt = x
x += (101, )
pvs = pvsystem.singlediode(*x, method='lambertw')
out = pvsystem.singlediode(*x, method=method)
isc, voc, imp, vmp, pmp, ix, ixx, i, v = out.values()
assert np.isclose(pvs['i_sc'], isc)
assert np.isclose(pvs['v_oc'], voc)
# the singlediode method doesn't actually get the MPP correct
pvs_imp = pvsystem.i_from_v(rsh, rs, nnsvt, vmp, io, il, method='lambertw')
pvs_vmp = pvsystem.v_from_i(rsh, rs, nnsvt, imp, io, il, method='lambertw')
assert np.isclose(pvs_imp, imp)
assert np.isclose(pvs_vmp, vmp)
assert np.isclose(pvs['p_mp'], pmp)
assert np.isclose(pvs['i_x'], ix)
pvs_ixx = pvsystem.i_from_v(rsh, rs, nnsvt, (voc + vmp)/2, io, il,
method='lambertw')
assert np.isclose(pvs_ixx, ixx)
def test_brentq_spr_e20_327():
"""test pvsystem.singlediode with Brent method on SPR-E20-327"""
spr_e20_327 = CECMOD.SunPower_SPR_E20_327
x = pvsystem.calcparams_desoto(
effective_irradiance=POA, temp_cell=TCELL,
alpha_sc=spr_e20_327.alpha_sc, a_ref=spr_e20_327.a_ref,
I_L_ref=spr_e20_327.I_L_ref, I_o_ref=spr_e20_327.I_o_ref,
R_sh_ref=spr_e20_327.R_sh_ref, R_s=spr_e20_327.R_s,
EgRef=1.121, dEgdT=-0.0002677)
il, io, rs, rsh, nnsvt = x
pvs = pvsystem.singlediode(*x, method='lambertw')
out = pvsystem.singlediode(*x, method='brentq')
isc, voc, imp, vmp, pmp, ix, ixx = out.values()
assert np.isclose(pvs['i_sc'], isc)
assert np.isclose(pvs['v_oc'], voc)
# the singlediode method doesn't actually get the MPP correct
pvs_imp = pvsystem.i_from_v(rsh, rs, nnsvt, vmp, io, il, method='lambertw')
pvs_vmp = pvsystem.v_from_i(rsh, rs, nnsvt, imp, io, il, method='lambertw')
assert np.isclose(pvs_imp, imp)
assert np.isclose(pvs_vmp, vmp)
assert np.isclose(pvs['p_mp'], pmp)
assert np.isclose(pvs['i_x'], ix)
pvs_ixx = pvsystem.i_from_v(rsh, rs, nnsvt, (voc + vmp)/2, io, il,
method='lambertw')
assert np.isclose(pvs_ixx, ixx)
return isc, voc, imp, vmp, pmp, pvs
def test_method_spr_e20_327(method, cec_module_spr_e20_327):
"""test pvsystem.singlediode with different methods on SPR-E20-327"""
spr_e20_327 = cec_module_spr_e20_327
x = pvsystem.calcparams_desoto(
effective_irradiance=POA, temp_cell=TCELL,
alpha_sc=spr_e20_327['alpha_sc'], a_ref=spr_e20_327['a_ref'],
I_L_ref=spr_e20_327['I_L_ref'], I_o_ref=spr_e20_327['I_o_ref'],
R_sh_ref=spr_e20_327['R_sh_ref'], R_s=spr_e20_327['R_s'],
EgRef=1.121, dEgdT=-0.0002677)
il, io, rs, rsh, nnsvt = x
pvs = pvsystem.singlediode(*x, method='lambertw')
out = pvsystem.singlediode(*x, method=method)
isc, voc, imp, vmp, pmp, ix, ixx = out.values()
assert np.isclose(pvs['i_sc'], isc)
assert np.isclose(pvs['v_oc'], voc)
# the singlediode method doesn't actually get the MPP correct
pvs_imp = pvsystem.i_from_v(rsh, rs, nnsvt, vmp, io, il, method='lambertw')
pvs_vmp = pvsystem.v_from_i(rsh, rs, nnsvt, imp, io, il, method='lambertw')
assert np.isclose(pvs_imp, imp)
assert np.isclose(pvs_vmp, vmp)
assert np.isclose(pvs['p_mp'], pmp)
assert np.isclose(pvs['i_x'], ix)
pvs_ixx = pvsystem.i_from_v(rsh, rs, nnsvt, (voc + vmp)/2, io, il,
method='lambertw')
assert np.isclose(pvs_ixx, ixx)
def test_brentq_spr_e20_327():
"""test pvsystem.singlediode with Brent method on SPR-E20-327"""
spr_e20_327 = CECMOD.SunPower_SPR_E20_327
x = pvsystem.calcparams_desoto(effective_irradiance=POA,
temp_cell=TCELL,
alpha_sc=spr_e20_327.alpha_sc,
a_ref=spr_e20_327.a_ref,
I_L_ref=spr_e20_327.I_L_ref,
I_o_ref=spr_e20_327.I_o_ref,
R_sh_ref=spr_e20_327.R_sh_ref,
R_s=spr_e20_327.R_s,
EgRef=1.121,
dEgdT=-0.0002677)
il, io, rs, rsh, nnsvt = x
pvs = pvsystem.singlediode(*x, method='lambertw')
out = pvsystem.singlediode(*x, method='brentq')
isc, voc, imp, vmp, pmp, ix, ixx = out.values()
assert np.isclose(pvs['i_sc'], isc)
assert np.isclose(pvs['v_oc'], voc)
# the singlediode method doesn't actually get the MPP correct
pvs_imp = pvsystem.i_from_v(rsh, rs, nnsvt, vmp, io, il, method='lambertw')
pvs_vmp = pvsystem.v_from_i(rsh, rs, nnsvt, imp, io, il, method='lambertw')
assert np.isclose(pvs_imp, imp)
assert np.isclose(pvs_vmp, vmp)
assert np.isclose(pvs['p_mp'], pmp)
assert np.isclose(pvs['i_x'], ix)
pvs_ixx = pvsystem.i_from_v(rsh,
rs,
nnsvt, (voc + vmp) / 2,
io,
il,
method='lambertw')
assert np.isclose(pvs_ixx, ixx)
return isc, voc, imp, vmp, pmp, pvs
def test_newton_fs_495():
"""test pvsystem.singlediode with Newton method on FS495"""
fs_495 = CECMOD.First_Solar_FS_495
x = pvsystem.calcparams_desoto(
effective_irradiance=POA, temp_cell=TCELL,
alpha_sc=fs_495.alpha_sc, a_ref=fs_495.a_ref, I_L_ref=fs_495.I_L_ref,
I_o_ref=fs_495.I_o_ref, R_sh_ref=fs_495.R_sh_ref, R_s=fs_495.R_s,
EgRef=1.475, dEgdT=-0.0003)
il, io, rs, rsh, nnsvt = x
x += (101, )
pvs = pvsystem.singlediode(*x, method='lambertw')
out = pvsystem.singlediode(*x, method='newton')
isc, voc, imp, vmp, pmp, ix, ixx, i, v = out.values()
assert np.isclose(pvs['i_sc'], isc)
assert np.isclose(pvs['v_oc'], voc)
# the singlediode method doesn't actually get the MPP correct
pvs_imp = pvsystem.i_from_v(rsh, rs, nnsvt, vmp, io, il, method='lambertw')
pvs_vmp = pvsystem.v_from_i(rsh, rs, nnsvt, imp, io, il, method='lambertw')
assert np.isclose(pvs_imp, imp)
assert np.isclose(pvs_vmp, vmp)
assert np.isclose(pvs['p_mp'], pmp)
assert np.isclose(pvs['i_x'], ix)
pvs_ixx = pvsystem.i_from_v(rsh, rs, nnsvt, (voc + vmp)/2, io, il,
method='lambertw')
assert np.isclose(pvs_ixx, ixx)
return isc, voc, imp, vmp, pmp, i, v, pvs
def test_i_from_v_from_i(fixture_v_from_i):
# Solution set loaded from fixture
Rsh = fixture_v_from_i['Rsh']
Rs = fixture_v_from_i['Rs']
nNsVth = fixture_v_from_i['nNsVth']
I = fixture_v_from_i['I']
I0 = fixture_v_from_i['I0']
IL = fixture_v_from_i['IL']
V = fixture_v_from_i['V_expected']
# Convergence criteria
atol = 1.e-11
I_expected = pvsystem.i_from_v(Rsh,
Rs,
nNsVth,
V,
I0,
IL,
method='lambertw')
assert_allclose(I, I_expected, atol=atol)
I = pvsystem.i_from_v(Rsh, Rs, nNsVth, V, I0, IL)
assert (isinstance(I, type(I_expected)))
if isinstance(I, type(np.ndarray)):
assert (isinstance(I.dtype, type(I_expected.dtype)))
assert (I.shape == I_expected.shape)
assert_allclose(I, I_expected, atol=atol)
def test_newton_fs_495():
"""test pvsystem.singlediode with Newton method on FS495"""
fs_495 = CECMOD.First_Solar_FS_495
x = pvsystem.calcparams_desoto(effective_irradiance=POA,
temp_cell=TCELL,
alpha_sc=fs_495.alpha_sc,
a_ref=fs_495.a_ref,
I_L_ref=fs_495.I_L_ref,
I_o_ref=fs_495.I_o_ref,
R_sh_ref=fs_495.R_sh_ref,
R_s=fs_495.R_s,
EgRef=1.475,
dEgdT=-0.0003)
il, io, rs, rsh, nnsvt = x
x += (101, )
pvs = pvsystem.singlediode(*x, method='lambertw')
out = pvsystem.singlediode(*x, method='newton')
isc, voc, imp, vmp, pmp, ix, ixx, i, v = out.values()
assert np.isclose(pvs['i_sc'], isc)
assert np.isclose(pvs['v_oc'], voc)
# the singlediode method doesn't actually get the MPP correct
pvs_imp = pvsystem.i_from_v(rsh, rs, nnsvt, vmp, io, il, method='lambertw')
pvs_vmp = pvsystem.v_from_i(rsh, rs, nnsvt, imp, io, il, method='lambertw')
assert np.isclose(pvs_imp, imp)
assert np.isclose(pvs_vmp, vmp)
assert np.isclose(pvs['p_mp'], pmp)
assert np.isclose(pvs['i_x'], ix)
pvs_ixx = pvsystem.i_from_v(rsh,
rs,
nnsvt, (voc + vmp) / 2,
io,
il,
method='lambertw')
assert np.isclose(pvs_ixx, ixx)
return isc, voc, imp, vmp, pmp, i, v, pvs
def test_singlediode_array():
# github issue 221
photocurrent = np.linspace(0, 10, 11)
resistance_shunt = 16
resistance_series = 0.094
nNsVth = 0.473
saturation_current = 1.943e-09
sd = pvsystem.singlediode(photocurrent,
saturation_current,
resistance_series,
resistance_shunt,
nNsVth,
method='lambertw')
expected = np.array([
0., 0.54538398, 1.43273966, 2.36328163, 3.29255606, 4.23101358,
5.16177031, 6.09368251, 7.02197553, 7.96846051, 8.88220557
])
assert_allclose(sd['i_mp'], expected, atol=0.01)
sd = pvsystem.singlediode(photocurrent, saturation_current,
resistance_series, resistance_shunt, nNsVth)
expected = pvsystem.i_from_v(resistance_shunt,
resistance_series,
nNsVth,
sd['v_mp'],
saturation_current,
photocurrent,
method='lambertw')
assert_allclose(sd['i_mp'], expected, atol=0.01)
def test_i_from_v(fixture_i_from_v, method, atol):
# Solution set loaded from fixture
Rsh = fixture_i_from_v['Rsh']
Rs = fixture_i_from_v['Rs']
nNsVth = fixture_i_from_v['nNsVth']
V = fixture_i_from_v['V']
I0 = fixture_i_from_v['I0']
IL = fixture_i_from_v['IL']
I_expected = fixture_i_from_v['I_expected']
I = pvsystem.i_from_v(Rsh, Rs, nNsVth, V, I0, IL, method=method)
assert (isinstance(I, type(I_expected)))
if isinstance(I, type(np.ndarray)):
assert (isinstance(I.dtype, type(I_expected.dtype)))
assert (I.shape == I_expected.shape)
assert_allclose(I, I_expected, atol=atol)
def test_i_from_v(fixture_i_from_v):
# Solution set loaded from fixture
Rsh = fixture_i_from_v['Rsh']
Rs = fixture_i_from_v['Rs']
nNsVth = fixture_i_from_v['nNsVth']
V = fixture_i_from_v['V']
I0 = fixture_i_from_v['I0']
IL = fixture_i_from_v['IL']
I_expected = fixture_i_from_v['I_expected']
# Convergence criteria
atol = 1.e-11
I = pvsystem.i_from_v(Rsh, Rs, nNsVth, V, I0, IL)
assert(isinstance(I, type(I_expected)))
if isinstance(I, type(np.ndarray)):
assert(isinstance(I.dtype, type(I_expected.dtype)))
assert(I.shape == I_expected.shape)
assert_allclose(I, I_expected, atol=atol)
def test_i_from_v_size():
with pytest.raises(ValueError):
pvsystem.i_from_v(20, [0.1] * 2, 0.5, [7.5] * 3, 6.0e-7, 7.0)
with pytest.raises(ValueError):
pvsystem.i_from_v(20, [0.1] * 2,
0.5, [7.5] * 3,
6.0e-7,
7.0,
method='brentq')
with pytest.raises(ValueError):
pvsystem.i_from_v(20,
0.1,
0.5, [7.5] * 3,
6.0e-7,
np.array([7., 7.]),
method='newton')
def test_i_from_v():
output = pvsystem.i_from_v(20, .1, .5, 40, 6e-7, 7)
assert_almost_equals(-299.746389916, output, 5)
def test_i_from_v():
output = pvsystem.i_from_v(20, .1, .5, 40, 6e-7, 7)
assert_allclose(-299.746389916, output, atol=1e-5)
def test_singlediode_series_ivcurve(cec_module_params):
times = pd.date_range(start='2015-06-01', periods=3, freq='6H')
effective_irradiance = pd.Series([0.0, 400.0, 800.0], index=times)
IL, I0, Rs, Rsh, nNsVth = pvsystem.calcparams_desoto(
effective_irradiance,
temp_cell=25,
alpha_sc=cec_module_params['alpha_sc'],
a_ref=cec_module_params['a_ref'],
I_L_ref=cec_module_params['I_L_ref'],
I_o_ref=cec_module_params['I_o_ref'],
R_sh_ref=cec_module_params['R_sh_ref'],
R_s=cec_module_params['R_s'],
EgRef=1.121,
dEgdT=-0.0002677)
out = pvsystem.singlediode(IL,
I0,
Rs,
Rsh,
nNsVth,
ivcurve_pnts=3,
method='lambertw')
expected = OrderedDict([
('i_sc', array([0., 3.01054475, 6.00675648])),
('v_oc', array([0., 9.96886962, 10.29530483])),
('i_mp', array([0., 2.65191983, 5.28594672])),
('v_mp', array([0., 8.33392491, 8.4159707])),
('p_mp', array([0., 22.10090078, 44.48637274])),
('i_x', array([0., 2.88414114, 5.74622046])),
('i_xx', array([0., 2.04340914, 3.90007956])),
('v',
array([[0., 0., 0.], [0., 4.98443481, 9.96886962],
[0., 5.14765242, 10.29530483]])),
('i',
array([[0., 0., 0.], [3.01079860e+00, 2.88414114e+00, 3.10862447e-14],
[6.00726296e+00, 5.74622046e+00, 0.00000000e+00]]))
])
for k, v in out.items():
assert_allclose(v, expected[k], atol=1e-2)
out = pvsystem.singlediode(IL, I0, Rs, Rsh, nNsVth, ivcurve_pnts=3)
expected['i_mp'] = pvsystem.i_from_v(Rsh,
Rs,
nNsVth,
out['v_mp'],
I0,
IL,
method='lambertw')
expected['v_mp'] = pvsystem.v_from_i(Rsh,
Rs,
nNsVth,
out['i_mp'],
I0,
IL,
method='lambertw')
expected['i'] = pvsystem.i_from_v(Rsh,
Rs,
nNsVth,
out['v'].T,
I0,
IL,
method='lambertw').T
expected['v'] = pvsystem.v_from_i(Rsh,
Rs,
nNsVth,
out['i'].T,
I0,
IL,
method='lambertw').T
for k, v in out.items():
assert_allclose(v, expected[k], atol=1e-2)
def test_i_from_v():
output = pvsystem.i_from_v(20, .1, .5, 40, 6e-7, 7)
assert_almost_equals(-299.746389916, output, 5)
def test_i_from_v():
output = pvsystem.i_from_v(20, .1, .5, 40, 6e-7, 7)
assert_allclose(-299.746389916, output, atol=1e-5)
