ABSTRACT

Due to the wide spread of power electronics equipment in modern
electrical systems, the increase of the harmonics disturbance in the ac mains
currents has became a major concern due to the adverse effects on all
equipment. Power electronic converters are commonly used for interfacing
distributed generation (DG) systems to the electrical power network.
However, the unbalanced voltage compensation may cause adverse effects on
the IFCs' operation such as output active power oscillation and DC link
voltage variations. Moreover, since the compensation is realized through the
available rating of IFCs, it is equally important to consider the effectiveness
of control strategy for unbalanced voltage compensation. Specially, the first
control strategy aims at minimizing the IFC's active power oscillation and
reducing the adverse effects of unbalanced voltage compensation on IFC's
operation. In DG systems a fast and accurate positive-sequence, fundamental
grid voltage frequency and magnitude tracking is required to synchronize grid
connected converter systems with the mains. The proposed System deals with
a Multi level inverter for DG systems mitigating power quality issues, such as
harmonics and reactive power compensation for grid-connected operation. It
performs the nonlinear load current harmonic compensation, mitigates
harmonics yielding more accurate and pure sine wave output. So Instead of
using inverter we can use multilevel inverters in the power system equipment.
Keywords: DG Systems, IFC, Unbalanced voltage compensation, Multi
level inverter.
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