Page 59 - Renewable Energy Devices and System with Simulations in MATLAB and ANSYS

46 Renewable Energy Devices and Systems with Simulations in MATLAB and ANSYS ®
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PV arrays DC–DC Central inverter
(optional)
LV/MV
trafo.

MV/MV
trafo. Grid

FIGURE 3.4 Large-scale PV power plant/station based on central inverters for utility applications, where
multilevel converters can be adopted as central inverters to manage even higher power of up to tens of mega-
watts (MW).

Optional
PV panels
DC DC LF
°C
DC AC
C p
(a)
PV panels
DC HF DC
°C
DC AC
C p
(b)
PV panels Optional
DC DC
°C
DC AC
C p
(c)
FIGURE 3.5 Single-phase grid-connected PV systems, where the AC-module inverters, the string invert-
ers, and the multistring inverters are commonly used: (a) with a low-frequency (LF) transformer, (b) with a
high-frequency (HF) transformer, and (c) without transformers. Note that C p represents the parasitic capacitor
between the PV panel and the ground.

DC–AC inverter AC filter
PV panels
DC link DC

Grid
°C C DC
C p AC

FIGURE 3.6 General block diagram of a single-stage single-phase PV topology (AC-module/string inverter
system) with an AC filter.