A grid connected photovoltaic system using a parallel multilevel
inverter: Optimal number of inverter cells
Abstract
This paper presents a grid connected photovoltaic (PV) system using a
parallel multicellular inverter (PMI). We focus on the optimized design
of an LCL filter connecting a parallel multicellular inverter by looking
for the number which optimizes the losses of the inverter, as well as
the energy management by controlling the power produced by the
photovoltaic generator (PVG). In order to transfer the power produced by
the PVG to the grid, the classical maximum power point tracking (MPPT)
algorithm called perturb and observe (P & O) is used to maximize the
power produced by the PVG. The active and reactive power control (PQ
control) using a Phase-Locked Loop (PLL) for synchronization is applied
to the inverter. We present the value of this innovative PV architecture
using a PMI compared to the conventional one. We show that this PQ
control, although it is classical, is well adapted to the PV
architecture using a PMI. We also present and discuss the simulation
results obtained by using the Matlab software (simulink and
simpowersystems).