The PV module parameter and properties, as well
as their behavior, are defined through a 6-sheet dialog:
|
Basic Data, |
Model type definition and
main STC parameters, |
|
|
+ Tool showing the main results
of the model, for any Irradiance and temperature conditions.
|
|
Additional data
|
Additional optional data specified for this module, and
tools for the elaboration of the model. |
|
|
Low-light efficiency - Measured
I/V curve - Sandia model parameters - IAM specifications -
secondary parameters. |
|
Size and Technology
|
Module and cells sizes, by-pass
diodes, secondary characteristics, other specifications |
| Graphs
|
a tool to visualize usual and
less usual graphs of the
PV-model behavior over a great variety of operating
conditions. |
Synthesis
of parameters associated with any module in PVSyst Database
:
"Basic
data":
| Tolerance:
|
+/- tolerances specified
for the Nominal power. Only used in PVsyst for establishing the
default value of the "Module
quality loss" factor (fixed at Low tol + a quarter of the
difference (High-Low)). |
| Technology
|
Gives choice for the main
technologies of PV modules available on the market. Acts on the
model. |
| GRef
|
Reference irradiance for the
(Isc, Voc, Impp, Vmpp) specifications.
Usually STC = 1000 W/m². |
| TRef
|
Reference temperature for the
(Isc, Voc, Impp, Vmpp) specifications. Usually STC =
25°C, |
| Isc
|
Short circuit current at
(GRef, TRef) conditions, |
| Voc
|
Open circuit voltage at
(GRef, TRef) conditions, |
| Impp
|
Max. power point current at
(GRef, TRef) conditions, |
| Vmpp
|
Max. power point voltage at
(GRef, TRef) conditions, |
| muIsc
|
Temperature coefficient on Isc
[mA/K] or [%/K] |
"Additional data
> Secondary parameters":
| LID loss
|
Sometimes specified by the
manufacturer |
Specified muVoc Normally muVoc is a result of the
model. An alternative value may be specified here according to the
datasheets.
|
|
This value may eventually be used
during the sizing (choice in the project's parameter
definitions) |
| Absorptivity
|
Light absorptivity for the
temperature evaluation through the thermal balance. Please let at
default value. |
| Nb of bypass diodes
|
Useful for the electrical shading
calculations in the Module Layout part. Normally 3 diodes for 60
and 72 cells, 4 diodes for 96 cells in series. |
| BRev
|
Special parameter for reverse
voltage behavior; negligible influence in the shading calculations.
Please let at default value.
|
"Model
parameters":
Parameters of the "standard"
one-diode model
| Rshunt
|
Shunt resistance at GRef.
Measured as the inverse of the slope of the I/V characteristics
around Isc at STC. If not specified, you can keep the value
proposed by PVsyst. |
| Rsh (G=0)
|
Intercept at G=0 of
the exponential behaviour of Rsh according to irradiance, |
| RshExp
|
Parameter of the exponential.
Without very reliable determination, let it at its default
value of 5.5. |
| Rseries, model
|
Series resistance involved in the
one-diode model. For crystalline modules, you can keep
the proposed value, which may be determined either according to a
pre-defined gamma value, or low-light performances. |
| Rserie max
|
Maximum possible value of Rserie.
A higher value would not allow the I/V characteristics to pass
through the 3 reference points. |
| Rserie app
|
Apparent series resistance, as
measured on the I/V curve as the inverse of the slope around Vco at
(GRef, TRef). This slope is the sum of the Rserie (model) and
the exponential effects. |
| Gamma
|
Diode Quality Factor, involved in the
"one-diode" model. |
| muGamma
|
Thermal (linear) correction
factor on Gamma, modification of the "standard" model for obtaining
a specified muPmpp if necessary. |
| IoRef
|
Diode saturation current,
involved in the "one-diode" model. |
| muVoc
|
Thermal behaviour of the Voc.
Related to Rserie, but the manufacturer data is usually not
attainable with reasonable other parameters. This value is a
result of the model, and will
usually not be compatible with the manufacturer's data. |
| muVocSpec
|
Specified manufacturer's data, may eventually be
used during the sizing if the PVsyst model is not suited.
|
| muPmpp
|
Normally a result of the model.
May be forced to a specified value by acting on the muGamma
parameter. |
| muPmppReq
|
Specified value for muPmpp
if required.
|
|
|
Parameters for the modifications of the
one-diode model for amorphous and CdTe technologies
|
| d²mutau
|
Specific parameter for the
contribution of the recombination loss parameter. The validity
domain of this value for finding a solution to the non-linear
equations is strongly correlated with Rshunt and Rserie. It
has implications on the thermal behaviour, especially of Vco. To
our experience with the long-term measurements of several amorphous
modules, the value of d²mutau parameter should be rather near to
its maximum possible (about 80 to 90%). |
| Spectral corr
|
Parametrized correction according
to Air mass and Kt.
Fixed correlation (from University of Loughborough), may
be activated or not. Not suited for CdTe technology.
|
"Sizes
and technology"
| NCell serie
|
Number of cells in series,
necessary for the determination of
the model, for one cell. |
| NCells parall
|
Number of cells in parallel, not
really used by the model. |
| Cell Area
|
Area of one cell, will give
sensitive area of the module, and allow the definition of a "cell"
efficiency; Not
necessary. |
| Module Length
|
Total length of the module.
Necessary for the calculation of the module efficiency, |
| Module Width
|
Total width of the module.
Necessary for the calculation of the module efficiency, |
| Apparent length
|
Tile modules or BIPV: if defined,
will be used for the efficiency instead of total length, |
| Apparent width
|
Tile modules or BIPV: if defined,
will be used for the efficiency instead of total width, |
| Max voltage IEC
|
Max. voltage allowed for the
array in worst conditions Voc(low temp) - i.e. insulation
voltage acc. to IEC standard (usually 1000 V), |
| Max voltage UL
|
Max. voltage allowed for the
array in worst conditions Voc(low temp) - i.e. insulation
voltage acc. to US standards (usually 600 V), |
