Due to the importance of the industrial growth in the North and in particular the Industrial
Pole of Manaus (PIM), it is important to have mathematical tools that facilitate the expert
decisions on the selection and sizing of harmonic filters needed to neutralize the harmful
effects of harmonics generated by nonlinear loads of industry and achieve compliance with
the power quality standards. Moreover, as the passive harmonic filters have the capacity to
generate reactive power to the network, they are effective compensating reactive power means
and therefore can achieve significant savings in sales of electric energy consumed by these
industrial facilities. This thesis aims to develop a mathematical method and a computational
tool for the selection of the configuration and the design parameters of a set of passive
harmonic filters for industrial electrical systems. In this direction, the optimization problem of
compensation of harmonics through passive filters is formulated as a multi-objective problem
that considers both the goals of reducing harmonic distortion as the economic effectiveness of
the project considering the characteristics of the Brazilian system of tariffs. Moreover, the
presented formulation considers relevant restrictions imposed by the national and foreign
standards. A computational solution to this problem was achieved using the NSGA-II genetic
algorithm which determines a set of Pareto optimal solutions (Frontier) that enable the
designer to choose the most appropriate solutions to the problem. Furthermore, the
computational tool developed has several new features as: not only calculates the parameters
that characterize the filters, but also selects the type of configuration and the number of
branches of the filter in each candidate bus according to a set of predetermined settings; has
implemented two standards for assessing the constraints of power quality (Prodist Modulo-8
and IEEE 519-92) that can be selected by the user; determines solutions with good
performance indicators for various characteristic and non-characteristic scenarios of the
system that allow to represent: the daily variations of the load as well as the variations of
system parameters and filters; evaluates the cost of energy bills in a grid that has different
industrial operating conditions (characteristic scenarios) and assesses the economic effect of
harmonic filters as reactive power compensators. To develop the computational tool of this
thesis, it was used a phase-coordinates model for the electric power grids of industrial and
services installations to program additional computational tools. These tools comprise a
frequency scan program, a harmonic power flow program for the harmonic current injection
method and a fundamental frequency power flow program. The positive results of this thesis,
from the analysis of several practical examples show the advantages of the developed method.
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