| Abstract |
This paper deals with the design, analysis and simulation of a four branch four wire shunt active power
filter, which compensates harmonic currents, neutral current and reactive power under balanced and
unbalanced supply network. An advanced control theory named p-q-r theory has been already
proposed by H. Kim et al [1]. The novelty with the control approach developed in this paper is the
manner to separate the continuous component from the alternative one. Indeed, our approach consists
on not to use a filter for extracting the continuous component but rather to identify it. It will be proved
that this new approach has the same result, in term of precision, as a second order filter with a low
cut-off frequency "fc= 20Hz", but the dynamic is comparable with that of a large cut-off frequency
"fc= 100 Hz". Moreover, we are going to propose a PLL with high performances and good results are
obtained when the main voltage are strongly unbalanced and contain harmonics. The simulation
results will illustrate the good performance of this new approach, specially a better dynamic
performance characteristics in comparison with the classical extraction methods. |
