the system. On the other hand, some
multilevel converter topologies, such
as the cascaded H-bridge converter or
the modular multilevel converter, can
take advantage of splitting the PV array
system to achieve higher efficiency
values using independent MPPT
algorithms. This could be interesting
for central inverters of PV mediumand
high-power plants [37]–[41].
Another research focus involves developing
PV inverters with additional
energy storage capability usually based
on batteries. These hybrid systems
present the advantages of improving
the frequency and voltage regulation,
storing the energy if it is not demanded
by local loads, and supplying this
energy when required, increasing the
overall system operation (usually called
peak load shaving). These systems are
mainly focused for stand-alone systems,
household applications, or weak
grid-connected applications of large PV
plants [42]–[45]. The use of hybrid PV
batteries can already be found as a commercial
product for household applications
(see, for instance, the Sunny Boy
3600/5000 Smart Energy by SMA) [46].
This trend emerges as an important field
of development for the future.
On the other hand, it is important
to note that the high penetration of PV
systems has led to the consideration o