Simulation variables: meteo, irradiance and PV array |
  
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Simulation variables: meteo, irradiance and PV array |
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The following variables are calculated during the simulation process, and available as results:
Meteorological data:
GlobHor Horizontal global irradiation, as read on the meteo file.
DiffHor Horizontal diffuse irradiation, read on the meteo file
BeamHor Horizontal beam irradiation, = GlobHor-DiffHor.
Tamb Ambient temperature, read on meteo file,
Windvel Wind velocity read on meteo file
If not present on file : monthly value, or default value (1.5m/s).
Incident energy in the collector plane
GlobInc Incident global irradiation in the collector plane
BeamInc Incident beam irradiation in the collector plane
DiffAInc Incident diffuse irradiation in the collector plane
(usual "diffuse" acception including albedo)
DiffSInc Incident diffuse irradiation (from sky) in the collector plane
AlbInc Incident albedo irradiation in the collector plane
Secondary indicators :
Bm/Gl Incident Beam/Global ratio = BeamInc / GlobInc
Diff/Gl Incident Diffuse/Global ratio = DiffInc / GlobInc
DifS/Gl Incident Sky diffuse/Global ratio = DifSInc / GlobInc
Alb/Gl Incident Albedo/Global ratio = AlbInc / GlobInc
Incident energy on collectors, corrected for optical losses
GlobHrz Global on collectors, corrected for horizon (far shadings)
GlobShd Global on collectors, corrected for horizon and near shadings
GlobIAM Global on collectors, corrected for horizon, near shadings and IAM
GlobSlg Global on collectors, corrected for horizon, near shadings, IAM and soiling
GlobEff "Effective" global, after all optical losses (shadings, IAM, soiling)
DiffEff "Effective" diffuse, corrected for all optical losses
"Effective" = irradiation effectively reaching the PV-cell surface.
Secondary optical factors (there are identical factors for Diffuse and Albedo)
FTransp Transposition factor = GlobInc / GlobHor
FHrzBm Horizon shading factor on beam = BeamHrz / BeamInc
FHrzGl Horizon shading factor on global = GlobHrz / GlobInc
FShdBm Near shading factor on beam = BeamShd / BeamHrz
FShdGl Near shadings factor on global = GlobShd / GlobHrz
FIAMBm IAM factor on beam component = BeamIAM / BeamShd
FIAMGl IAM factor on global component = GlobIAM / GlobShd
FSlgBm Soiling loss factor on beam = BeamSlg / BeamIAM
FSlgGl Soiling loss factor on global = GlobSlg / GlobIAM
Specific variables for bi-facial systems simulation
GlobGnd Global incident on ground, below the system.
ReflLss Ground reflexion loss (albedo)
BkVFLss Loss due to the view Factor for rear side
BackShd Shading loss on the rear side (mechanical structures between ground and rear side)
DifSBak Sky diffuse directly reaching the rear side
BmIncBk Beam incident on the rear side (morning/evening in Summer)
BmSFBak Beam shading factor on the rear side
BeamBak Bean effective (after shadings) on the rear side
GlobBak Global irradiance on the rear side
ReflFrt Ground reflexion on the Front side (added to GlobEff)
PV array virtual productions for loss evaluations
| EArrRef | Array Reference Energy for the PR evaluation. |
| Virtual energy produced according to the manufacturer specification Pnom (nameplate) |
| The reference installed power is equal to PNom (nameplate) * Number of PV modules. |
| Equivalent to the Yr normalised value. Not shown on the report. |
| EArrNom | Array Nominal energy at STC, starting point for the loss diagram |
| Virtual energy produced at TRef (STC: 25°C) according to the PV model |
| This may differs from the preceding as it is based on the model's Pmpp result instead of PNom, which may be slightly different. |
PV array losses and MPP running
| GIncLss | PV loss due to irradiance level |
| This is the effect of the low-light efficiency of the PV module (efficiency with respect to effic. at 1000 W/m2) |
| TempLss | PV loss due to array temperature |
| Difference E(GlobEff, TMod) with respect to model calculated at Tmodule = 25°C |
| SpctCor | Spectral correction (for amorphous or CdTe modules) |
| Calculated from the Spectral correction model amorphous) or the specific model from FirstSolar for CdTe. |
| ModQual | Module Quality loss |
| fixed constant parameter, |
| MisLoss | Module mismatch loss |
| fixed constant parameter for MPP or fixed V operation, depending on system, |
| OhmLoss | Ohmic wiring loss |
| calculated at each hour with the real array current |
| EArrMPP | Array virtual energy at MPP (after wiring and mismatch losses), |
| Virtual calculation independent of the system running (inverter, regulator) |
| Tarray | Average module temperature during operation |
| DTArr | Temperature difference between modules and ambient' |
| DTArrGl | DTArr weighted by "effective" global' irradiation |
| TExtON | Average ambient temperature during system operation. |
Further simulation variables are system-dependent:
-- DC-grid system.