The format file defines all characteristics
governing the custom source file reading (Meteo or Measured data
files).
The format of
the source-file may be very varied; however it has to fulfil the
following minimal criteria:
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Include the values of one time
step (hourly or sub-hourly) per text line. Each line ends with the
characters CR,LF, or only LF.
Sub-hourly records are gathered in order
to give PVsyst hourly internal records. |
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Comment lines at the beginning of
the file, or of each day or month, can be skipped. |
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Data are organized in columns,
with a chosen
separator (semi-colon, comma, TAB, blank, etc. )
or fixed widths. PVsyst accepts a great variety of date formats,
and adjusts the source data physical units. |
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The available parameters should
include the minimal data
which allow the calculation of the horizontal global and the ambient temperature.
Since simulation also requires the
horizontal diffuse irradiation, this is calculated, for example,
horizontal global and beam data. If not available, the diffuse
irradiation is reconstituted using the
Erbs correlation. |
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With measured data, if only the
irradiation in the collector
plane is available, the program calculates the corresponding
horizontal global and diffuse (inverse of the transposition).
Nevertheless, due to edge effects, these
data will only be valid within the original collector plane. |
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Usually the values are
consecutive; but if values are missing on the source file (for
example night values), the date should be explicitly mentioned on
each line of data.
Given that the internal file must hold
complete days, the data for any missing hour will be completed with
zero irradiation values, and with stable temperatures after the
last available reading. |
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Gaps of more than one day may be
acceptable with the option of writing the date for each reading on
the internal file. |
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It is also possible to
automatically chain data
monthly or daily files, provided that their name include
exploitable identification code (date). |
