Microcontroller-based harmonic analyzer

In today?s world, electric energy, which we use at every moment of our lifes and in whole industrial activities, has become a natural necessity. Because of the increasing demand for electric energy, different types of loads and circuit topologies have been used. Electrical devices used in our homes and most of industrial systems include non-linear loads, therefore harmonics ? other than the fundamental harmonic component, create problems on city?s electrical network and on other signals. For this reason, many countries determined standards for tolerable harmonic ranges. Consequently the process of harmonic measurement has become vital. The values obtained from the measurements made engineers design systems which remove harmonic effects. In this thesis, a microcontroller-based system containing a PC grafical user interface for measuring harmonics on city?s electrical network or on any voltage waveform has been designed. In chapter one, the concept of harmonic theory is introduced and harmonic sources are briefly explained. In chapter two, technical and physical specifications of some harmonic analyzers are compared and information about an academic work is given. In chapter three, harmonic analysis is narrated and Fourier Transform is comprehensively explained with helpful examples. In chapter four, hardware and software used in realizing microcontroller-based harmonic analyzer ? the subject of this thesis, are widely narrated in detail. In the fifth chapter, numerical results showing the performance of the microcontroller-based harmonic analyzer under different inputs are given and the results are discussed. In the final chapter, results obtained from this thesis and some possible system-improving future works are given. Keywords : Harmonic analysis, Fast Fourier Transform (FFT), 8051 microcontroller