CONCLUSION
From this study, it is observed that the performance of a Spy
water pumping system depends mainly on the power output of
module technology at specified VFD bus-bar voltage, which
varies with operating temperature in different seasons. So, a
Spy water pumping system should be selected based on its
performance vs. input power from the PV module technology.
The sizing of its PV array should be done based on its time of
operation as there are no formal MPPT available with VFD
controllers. A loss of more than 25% in water output from in
winter and summer SEASON is observed at NISE, if improperly
designed VFD controllers are used. Therefore, designing of
PV array for Spy water pumping systems must be done taking
into account the loss of power due to high voltage operation,
and effect of module temperature on voltage in summer
season if the pump is to be operated for whole year.