Guilherme Pedrosa
Before diving into solar simulations with PVLib, one of the main concerns I had was how to use the same inputs given to PVSyst, the de facto standard software of the solar industry. That also meant using the same files that describe the main equipments: PAN files for the modules and OND files for the inverters.
Although It surprised me that PVLib did not come with a PVSyst file’s parser, It was not a deal breaker. The search for such a parser led me to pvsyst_tools. The library worked perfectly for the PAN file I had at hand. Here’s a quick demo loading the library and PAN file from a local folder:
import os, sys
spath = '~/Projects/solar/'
print('current workign directory: {}'.format(spath))
sys.path.append(os.path.join(spath,'libs'))
import pvsyst
print('pvsyst module path: {}'.format(pvsyst.__file__))
import logging
logger = logging.getLogger('pysyst')
logger.setLevel(10) # 5 for Verbose 10 for Debug
pan = os.path.join(spath,'refs','CS6W-545MB-AG_CSI_EXT_1500V_V7_10_20210419.PAN') # example PAN file
# parse .PAN file into dict
module_parameters = pvsyst.pan_to_module_param(pan) # return two dicts
module_parameters
{'Manufacturer': 'CSI Solar Co., Ltd.',
'Model': 'CS6W-545MB-AG 1500V',
'Technol': 'mtSiMono',
'DataSource': 'Manufacture 2020 TUV-SUD data',
'YearBeg': '2020',
'Comment': 'www.csisolar.com',
'Width': 1.134,
'Height': 2.266,
'Depth': 0.035,
'Weight': 32.2,
'RelEffic800': 0.27,
'RelEffic400': -0.21,
'RelEffic200': -1.8,
'NCelS': 72,
'NCelP': 2,
'NDiode': 3,
'GRef': 1000.0,
'TRef': 25.0,
'PNom': 545.0,
'PNomTolLow': '0.00',
'PNomTolUp': '1.80',
'Isc': 13.95,
'Voc': 49.4,
'Imp': 13.14,
'Vmp': 41.5,
'muISC': 6.98,
'muVocSpec': -128.4,
'mIsc_percent': 0.05003584229390681,
'mVoc_percent': -0.259919028340081,
'muPmpReq': -0.34,
'RShunt': 2500.0,
'Rp_0': 10000.0,
'Rp_Exp': 5.5,
'RShunt_stc': 2530.6507857884803,
'RSerie': 0.206,
'Gamma': 0.98,
'muGamma': -0.0004,
'REM_Str_1': 'Frame: Anodized aluminium alloy',
'REM_Str_2': 'Structure: 2.0mm Glass / EVA / 2.0mm Glass',
'REM_Str_3': 'Connections: Cable,T4 series or H4 UTX or MC4-EVO2',
'IAM_Point_1': '20.0,1.00000',
'IAM_Point_2': '40.0,1.00000',
'IAM_Point_3': '60.0,1.00000',
'IAM_Point_4': '65.0,0.99000',
'IAM_Point_5': '70.0,0.96000',
'IAM_Point_6': '75.0,0.92000',
'IAM_Point_7': '80.0,0.84000',
'IAM_Point_8': '85.0,0.72000',
'IAM_Point_9': '90.0,0.00000',
'IAM': array([[20. , 40. , 60. , 65. , 70. , 75. , 80. , 85. , 90. ],
[ 1. , 1. , 1. , 0.99, 0.96, 0.92, 0.84, 0.72, 0. ]]),
'OperPoint_Point_1': 'False,800,25.0,0.27,0.00,0.000,0.000,0.00',
'OperPoint_Point_2': 'False,600,25.0,0.14,0.00,0.000,0.000,0.00',
'OperPoint_Point_3': 'False,400,25.0,-0.21,0.00,0.000,0.000,0.00',
'OperPoint_Point_4': 'False,200,25.0,-1.80,0.00,0.000,0.000,0.00',
'I_o_ref': 2.0352320417866327e-11,
'EgRef': 1.121,
'manufacturer': 'CSI Solar Co., Ltd.',
'module_name': 'CS6W-545MB-AG 1500V',
'Pmpp': 545.0,
'Impp': 13.14,
'Vmpp': 41.5,
'mIsc': 0.00698,
'mVocSpec': -0.12840000000000001,
'mPmpp': -0.34,
'Rshunt': 2500.0,
'Rsh 0': 10000.0,
'Rshexp': 5.5,
'Rserie': 0.206,
'gamma_ref': 0.98,
'mu_gamma': -0.0004,
'I_L_ref': 13.95,
'R_sh_ref': 2530.6507857884803,
'R_sh_0': 10000.0,
'R_s': 0.206,
'R_sh_exp': 5.5,
'cells_in_series': 72,
'alpha_sc': 0.00698}
To parse the OND file, however, I had to patch the inverter.py file from the pvsyst_tools library to include an extra section called ProfilPIO. That is why I decided to load the library form a local copy in the previous example. Here’s the patch:
ond_sections ={'PVObject_': 'pvGInverter',
'PVObject_Commercial': 'pvCommercial',
'Converter': 'TConverter',
'Remarks, Count': 'Remarks',
'ProfilPIO': 'ProfilPIO',
'ProfilPIOV1': 'ProfilPIOV1',
'ProfilPIOV2': 'ProfilPIOV2',
'ProfilPIOV3': 'ProfilPIOV3'}
With this patch in place, the same logic and procedure was applied to retrieve the inverter parameters:
ond_dir = r'refs' # directory of OND files}
ond = os.path.join(spath,ond_dir,'Sungrow_SG3125HV-30_V50_20200903_PVsyst.6.6.7.OND') # example PAN file
# parse .OND file into dict
inverter_parameters = pvsyst.ond_to_inverter_param(ond) # return two dicts
inverter_parameters
{'pvGInverter': {'Comment': 'Sungrow\tSG3125HV-30\tManufacturer 2020',
'Version': '6.67',
'ParObj1': '2020',
'Flags': '$003C1463',
'pvCommercial': {'Comment': 'Sungrow Power Supply Co., Ltd',
'Flags': '$0041',
'Manufacturer': 'Sungrow',
'Model': 'SG3125HV-30',
'DataSource': 'Manufacturer 2020',
'YearBeg': '2020',
'Width': '2.250',
'Height': '2.350',
'Depth': '1.160',
'Weight': '2700.00',
'NPieces': '100',
'PriceDate': '26/11/15 14:00',
'Currency': 'EUR'},
'Transfo': 'Without',
'TConverter': {'PNomConv': '3125.000',
'PMaxOUT': '3437.000',
'VOutConv': '600.0',
'VMppMin': '875',
'VMPPMax': '1300',
'VmppNom': '1100.0',
'VAbsMax': '1500',
'PSeuil': '3125.0',
'EfficMax': '99.00',
'EfficEuro': '98.70',
'FResNorm': '3.00',
'ModeOper': 'MPPT',
'CompPMax': 'Lim',
'CompVMax': 'Lim',
'MonoTri': 'Tri',
'ModeAffEnum': 'Efficiencyf_POut',
'UnitAffEnum': 'kW',
'IDCMax': '0.0',
'INomAC': '3007.0',
'IMaxAC': '3308.0',
'TPNom': '50.0',
'TPMax': '45.0',
'TPLim1': '52.0',
'TPLimAbs': '60.0',
'PLim1': '2500.000',
'PInEffMax ': '952507.900',
'PThreshEff': '5673.4',
'HasdefaultPThresh': 'False',
'ProfilPIO': {'NPtsMax': '11',
'NPtsEff': '8',
'LastCompile': '$8089',
'Mode': '1',
'Point_1': '12500.0,0.0',
'Point_2': '75000.0,69249.5',
'Point_3': '125000.0,119172.4',
'Point_4': '250000.0,243901.1',
'Point_5': '500000.0,493020.8',
'Point_6': '750000.0,741690.6',
'Point_7': '1500000.0,1485000.0',
'Point_8': '2500000.0,2469779.2',
'Point_9': '0.0,0.0',
'Point_10': '0.0,0.0',
'Point_11': '0.0,0.0'},
'VNomEff': '875.0,1100.0,1300.0,',
'EfficMaxV': '99.030,98.860,98.690,',
'EfficEuroV': '98.810,98.627,98.421,',
'ProfilPIOV1': {'NPtsMax': '11',
'NPtsEff': '9',
'LastCompile': '$8089',
'Mode': '1',
'Point_1': '3125.0,0.0',
'Point_2': '163952.7,159280.0',
'Point_3': '320420.6,315390.0',
'Point_4': '635380.4,628010.0',
'Point_5': '792268.9,783950.0',
'Point_6': '949459.8,940250.0',
'Point_7': '1580566.0,1563970.0',
'Point_8': '2370556.7,2342110.1',
'Point_9': '3155956.3,3115560.1',
'Point_10': '0.0,0.0',
'Point_11': '0.0,0.0'},
'ProfilPIOV2': {'NPtsMax': '11',
'NPtsEff': '9',
'LastCompile': '$8089',
'Mode': '1',
'Point_1': '3125.0,0.0',
'Point_2': '164523.1,158880.0',
'Point_3': '321647.8,315440.0',
'Point_4': '636356.2,627320.0',
'Point_5': '793900.1,783500.0',
'Point_6': '950465.2,939630.0',
'Point_7': '1582454.6,1563939.9',
'Point_8': '2372756.9,2342860.1',
'Point_9': '3170945.7,3124649.9',
'Point_10': '0.0,0.0',
'Point_11': '0.0,0.0'},
'ProfilPIOV3': {'NPtsMax': '11',
'NPtsEff': '9',
'LastCompile': '$8089',
'Mode': '1',
'Point_1': '3125.0,0.0',
'Point_2': '165697.0,158920.0',
'Point_3': '323254.1,315690.0',
'Point_4': '637521.6,627640.0',
'Point_5': '795473.8,783860.0',
'Point_6': '952507.9,940030.0',
'Point_7': '1585300.1,1563740.0',
'Point_8': '2376773.2,2342310.1',
'Point_9': '3177379.0,3125270.0',
'Point_10': '0.0,0.0',
'Point_11': '0.0,0.0'}},
'NbInputs': '18',
'NbMPPT': '2',
'TanPhiMin': '-0.750',
'TanPhiMax': '0.750',
'NbMSInterne': '2',
'MasterSlave': 'No_M_S',
'IsolSurvey ': 'Yes',
'DC_Switch': 'Yes',
'AC_Switch': 'Yes',
'DiscAdjust': 'Yes',
'MS_Thresh': '0.8',
'Night_Loss': '120.00'}}
How to use the resulting dictionaries with the inverter and module parameters is a different story, better left for another post.
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