Alencon SPOT: Installation,
Operation, and Maintenance Manual
15 |
P a g e
Neither of these requirements can be met by the transformer-less string inverter alone.
DC
AC
INVERTER
Distribution
tramsformer
TRANSFORMER
PV STRINGS
GALVANICALLY
ISOLATED SPOT
F
IGURE
8
:
A
TYPICAL
600V
PV
PLANT WITH
A
LENCON SPOTS AND A TRANSFORMER
-
LESS
INVERTER
The SPOT as shown in Figure 8 resolves both problems because the SPOT essentially serves
as a DC transformer. The SPOT will map the lower PV voltage range into the higher DC input
range of the new, transformer-less string inverter. At the same time, the SPOT will reintroduce
the galvanic isolation lost when the transformer from the older inverter was removed.
The SPOT provides galvanic isolation between PV and the ground potential of the primary
winding of the MV distribution transformer assuring that any mismatches in ground potential
are automatically resolved.
