MI 3109 EurotestPV Lite
Appendix E
– PV measurements – calculated values
73
Ptheo
Theoretical power of string at measured irradiance
Pnom
nominal power of panel at STC
Irr
stc
nominal irradiance at STC (Irr
stc
= 1000 W/m
2
)
Irr
measured irradiance
M
number of modules in serial
N
number of modules in parallel
Depending on temperature criterion for PASS is:
If
Tamb < 25 °C
or
Tcell < 40 °C
=>
η
2
>0.85
If
Tamb > 25 °C
or
Tcell > 40 °C
=>
η
2
>(1-
η
PV
-0.08),
where
η
PV
is calculated depending on type of temperature being measured as
or
,
where NOCT is nominal operating temperature of the cell (data supplied by the
panels manufacturer) and γ is coeff. of temperature of power characteristic of PV
module (inserted value from 0,01 to 0,99) (data supplied by the panels
manufacturer).
NOCT
nominal operating temperature of the cell (data supplied by the panels
manufacturer)
γ
coeff. of temperature of power characteristic of PV module (inserted
value from 0,01 to 0,99) (data supplied by the panels manufacturer)
2. inverter:
AC
DC
P
P
.
Calculation of conversion efficiency with comparison of STC and measured-
corrected values
(U, I (AC, DC), phase, Irr
stc
, Tstc, Pnom, Irr, Tcell, Rs, α, β, Isc, M, N)
