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Fix nominal annual output number for calculation
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@mjprilliman
mjprilliman committed Oct 9, 2023
1 parent 7bd3ffa commit 2e6e4db
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Showing 2 changed files with 18 additions and 8 deletions.
2 changes: 1 addition & 1 deletion shared/lib_shared_inverter.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -343,7 +343,7 @@ void SharedInverter::calculateACPower(const double powerDC_kW_in, const double D
powerConsumptionLoss_kW = 0.;
powerNightLoss_kW = 0.;
efficiencyAC = NONE_INVERTER_EFF;
powerAC_Watts = powerDC_Watts * efficiencyAC;
powerAC_Watts_clipping = powerDC_Watts * efficiencyAC;
}


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24 changes: 17 additions & 7 deletions ssc/cmod_pvsamv1.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1331,6 +1331,7 @@ void cm_pvsamv1::exec()
*********************************************************************************************** */
std::vector<double> dcPowerNetPerMppt_kW; //Vector of Net DC power in kW for each MPPT input on the system for THIS TIMESTEP ONLY
std::vector<double> dcPowerNetPerSubarray; //Net DC power in W for each subarray for THIS TIMESTEP ONLY
std::vector<double> dcPowerNetPerSubarrayCS;
std::vector<double> dcVoltagePerMppt; //Voltage in V at each MPPT input on the system for THIS TIMESTEP ONLY
std::vector<std::vector<double>> dcStringVoltage; // Voltage of string for each subarray
double dcPowerNetTotalSystem = 0; //Net DC power in W for the entire system (sum of all subarrays)
Expand Down Expand Up @@ -1400,6 +1401,7 @@ void cm_pvsamv1::exec()
}
for (size_t nn = 0; nn < PVSystem->numberOfSubarrays; nn++) {
dcPowerNetPerSubarray.push_back(0);
dcPowerNetPerSubarrayCS.push_back(0);
std::vector<double> tmp;
dcStringVoltage.push_back(tmp);
}
Expand Down Expand Up @@ -2326,6 +2328,7 @@ void cm_pvsamv1::exec()

// self-shading derate (by default it is 1.0 if disbled)
Subarrays[nn]->Module->dcPowerW *= Subarrays[nn]->poa.nonlinearDCShadingDerate;
Subarrays[nn]->Module->dcPowerWCS *= Subarrays[nn]->poa.nonlinearDCShadingDerate;
if (iyear == 0 || save_full_lifetime_variables == 1) mpptVoltageClipping[nn] *= Subarrays[nn]->poa.nonlinearDCShadingDerate;

// Sara 1/25/16 - shading database derate applied to dc only
Expand Down Expand Up @@ -2357,9 +2360,11 @@ void cm_pvsamv1::exec()
PVSystem->p_snowCoverage[nn][idx] = (ssc_number_t)(Subarrays[nn]->snowModel.coverage);
if (iyear == 0) annual_snow_loss += (ssc_number_t)(util::watt_to_kilowatt * Subarrays[nn]->dcPowerSubarray * smLoss);
Subarrays[nn]->dcPowerSubarray *= (1 - smLoss);
Subarrays[nn]->dcPowerSubarrayCS *= (1 - smLoss);
}

Subarrays[nn]->Module->dcPowerW *= (1 - smLoss);
Subarrays[nn]->Module->dcPowerWCS *= (1 - smLoss);
if (iyear == 0 || save_full_lifetime_variables == 1) mpptVoltageClipping[nn] *= (1 - smLoss);
}

Expand Down Expand Up @@ -2388,14 +2393,18 @@ void cm_pvsamv1::exec()

// apply pre-inverter power derate
dcPowerNetPerSubarray[nn] = Subarrays[nn]->dcPowerSubarray * (1 - Subarrays[nn]->dcLossTotalPercent);
dcPowerNetPerSubarrayCS[nn] = Subarrays[nn]->dcPowerSubarrayCS * (1 - Subarrays[nn]->dcLossTotalPercent);

//module degradation and lifetime DC losses apply to all subarrays
if (save_full_lifetime_variables == 1)
if (save_full_lifetime_variables == 1) {
dcPowerNetPerSubarray[nn] *= PVSystem->dcDegradationFactor[iyear];
dcPowerNetPerSubarrayCS[nn] *= PVSystem->dcDegradationFactor[iyear];
}

//dc adjustment factors apply to all subarrays
if (iyear == 0) annual_dc_adjust_loss += dcPowerNetPerSubarray[nn] * (1 - dc_haf(iyear * nrec + inrec)) * util::watt_to_kilowatt * ts_hour; //only keep track of this loss for year 0, convert from power W to energy kWh
dcPowerNetPerSubarray[nn] *= dc_haf(iyear * nrec + inrec);
dcPowerNetPerSubarrayCS[nn] *= dc_haf(iyear * nrec + inrec);

//lifetime daily DC losses apply to all subarrays and should be applied last. Only applied if they are enabled.
if (PVSystem->enableDCLifetimeLosses)
Expand All @@ -2408,13 +2417,14 @@ void cm_pvsamv1::exec()
}
if (iyear == 0) annual_dc_lifetime_loss += dc_lifetime_loss;
dcPowerNetPerSubarray[nn] *= (100 - PVSystem->dcLifetimeLosses[dc_loss_index]) / 100;
dcPowerNetPerSubarrayCS[nn] *= (100 - PVSystem->dcLifetimeLosses[dc_loss_index]) / 100;
}

//assign net DC power output
PVSystem->p_systemDCPower[idx] += (ssc_number_t)(dcPowerNetPerSubarray[nn] * util::watt_to_kilowatt);

//Clearsky DC Power
PVSystem->p_systemDCPowerCS[idx] += (ssc_number_t)(Subarrays[nn]->dcPowerSubarrayCS * util::watt_to_kilowatt);
PVSystem->p_systemDCPowerCS[idx] += (ssc_number_t)(dcPowerNetPerSubarrayCS[nn] * util::watt_to_kilowatt);

//add this subarray's net DC power to the appropriate MPPT input and to the total system DC power
PVSystem->p_dcPowerNetPerMppt[Subarrays[nn]->mpptInput - 1][idx] += (ssc_number_t)(dcPowerNetPerSubarray[nn]); //need to subtract 1 from mppt input number because those are 1-indexed
Expand Down Expand Up @@ -2541,12 +2551,12 @@ void cm_pvsamv1::exec()
}
for (size_t inrec = 0; inrec < nrec; inrec++) {
idx = inrec;
double dcPower_kW_csky = PVSystem->p_systemDCPowerCS[idx];
double dcPower_kW_nominal = PVSystem->p_systemDCPower[idx];
//Calculate DNI clearness index (time step basis)
double dni_clearness_index = PVSystem->p_DNIIndex[0][idx];
//double dni_clearness_index = PVSystem->p_DNIIndex[0][idx];
//Calculate Clipping Potential ((P_dc,dryclean - P_ac,0) / P_ac,0) (time step basis)
sharedInverter->calculateACPower(dcPower_kW_csky, PVSystem->p_mpptVoltage[0][idx], Irradiance->weatherRecord.tdry, as_boolean("enable_subhourly_clipping")); //DC batteries not allowed with multiple MPPT, so can just use MPPT 1's voltage
nominal_annual_clipping_output += sharedInverter->powerAC_kW_clipping;
sharedInverter->calculateACPower(dcPower_kW_nominal, PVSystem->p_mpptVoltage[0][idx], Irradiance->weatherRecord.tdry, as_boolean("enable_subhourly_clipping")); //DC batteries not allowed with multiple MPPT, so can just use MPPT 1's voltage
nominal_annual_clipping_output += sharedInverter->powerAC_kW_clipping; //AC nominal output
/*
double clip_pot = (dcPower_kW_csky - sharedInverter->powerAC_kW_clipping) / sharedInverter->powerAC_kW_clipping;
//Lookup matrix for percentage effect based on DNI index, Clipping potential //Lookup bias error in matrix (unitless) [CP, DNI]
Expand Down Expand Up @@ -2699,7 +2709,7 @@ void cm_pvsamv1::exec()
//Calculate DNI clearness index (time step basis)
double dni_clearness_index = PVSystem->p_DNIIndex[0][idx];
//Calculate Clipping Potential ((P_dc,dryclean - P_ac,0) / P_ac,0) (time step basis)
sharedInverter->calculateACPower(dcPower_kW_csky, dcVoltagePerMppt[0], Irradiance->weatherRecord.tdry, as_boolean("enable_subhourly_clipping")); //DC batteries not allowed with multiple MPPT, so can just use MPPT 1's voltage
//sharedInverter->calculateACPower(dcPower_kW_csky, dcVoltagePerMppt[0], Irradiance->weatherRecord.tdry, as_boolean("enable_subhourly_clipping")); //DC batteries not allowed with multiple MPPT, so can just use MPPT 1's voltage
//double clip_pot = (dcPower_kW_csky - sharedInverter->powerAC_kW_clipping) / sharedInverter->powerAC_kW_clipping;
double clip_pot = (dcPower_kW_csky - paco ) / (paco);

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