الفهرس يوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
Due to the widespread of the non-linear loads,harmonic currents and voltages are increasing.
Harmonics have bad effects on power system and communication networks. Due to these bad effects,it is important to
eliminate or even reduce the harmonics and improve the systems performance.
Chapter one is an introduction to the thesis, which includes the aim of the
work,the problems that harmonics cause, the economical benefits from reducing the harmonics and the methods of harmonic reduction. This chapter
is a brief on all the thesis contents.
Chapter two describes the meaning of harmonics; their bad effects, sources of
harmonics and economical benefits for reducing the harmonics and improving the power factor. A brief survey about the passive filters as a method of reducing the harmonics and improving the power factor is presented.
Chapter three deals with the basic principle of active filters. This chapter also describes the different topologies of active filters such as parallel active filters,series active filters,hybrid Filters and zero current switching filter and describes the hardware configuration of the active filters.
Chapter four describes the methods of control the pulse width modulator
(PWM) and obtaining the reference current. Different methods for obtaining
the reference current are presented such as band pass filter Fryze methods,
Fast Fourier Transform instantaneous reactive power theory Kalman filter.
Chapter five represents the simulation results of active parallel power filter,
series active power filter parallel filter with fuzzy logic controller and
finally zero current switching filter.
Chapter six is the conclusions and future work.