PV*SOL Expert 6.0 - Manual - Valentin Software

PV*SOL Expert 6.0 - Manual
Stand-Alone System Inverter Voltage Check
For the AC appliances, the battery voltage is compared with the inverter voltage. Both
components are loaded from the database and have to be checked against the system
voltage.
Battery Voltage Check
If your system has direct battery connection, the battery voltage sets the modules’ working
point. The battery voltage is dependent on the charge condition. PV*SOL ® works with a
characteristic curve for the (averaged) voltage.
These benchmark figures are compared with two working points for the modules’ MPP
voltage, ie the MPP voltage at 500 W/m² and 25°C, and at 1000 W/m² and 25 C (STC)
A message appears if the minimum battery voltage is less than 60% and the maximum
battery voltage is larger than the corresponding MPP voltage.
Simulation is blocked if the minimum battery voltage is less than 40% and the maximum
greater than 110% of the corresponding MPP voltage.
MPP Tracker Output Check
If an MPP tracker is used, a check is required to see if the MPP tracker’s output
corresponds to the PV output. If the figure is exceeded the PV energy produced will be
reduced, if the figure is not reached the MPP tracker works at a poor efficiency rate.
A message appears if the MPP tracker’s output is less than 90% and more than 120% of
the PV output. MPP tracker outputs less than 33% and more than 500% of the PV output
are not accepted.
MPP Voltage Check
The MPP tracker’s MPP tracking range is compared with the module array’s MPP voltages.
The voltage decreases with increasing temperature and decreasing radiation. The
definition of the working points is as described in the grid connected system check.
For both of these working points the module array’s MPP voltage is calculated and
compared with the MPP tracker’s MPP tracking range.
A message warning of discrepancies appears if the MPP tracker’s threshold values vary by
more or less than 10% from the modules. Not reaching the lower MPP threshold of around
50% or exceeding the upper MPP threshold of around 25% is not permitted.
Cabling checks are made on both types of systems, and on each PV array.
DC Cabling Check
The flow of current through the cabling under standard test conditions (STC) is defined by
the module current flow under STC and the number of parallel-connected modules in an
array. This should not be more than the permitted electrical capacity of the cabling.
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