My Master's thesis deals with the causes that affect the harmonic distortion at the point of common coupling. At the beginning of the thesis is a description of the model and its elements. Then, there are three different operating situations with the results. The results were analyzed with FFT.
Then I made frequency scanning, which I have described in more detail. The scanning has been done in two different ways, with and without considering the thyristor rectifier. When I acquired impedance, I was able to separate measurements in two parts, on the network and on the consumer contribution.
In this master thesis I have described three methods which I have used to get the frequency characteristics and determination of the contribution to the overall harmonic distortion. The first two methods I used for the determination of the frequency characteristics.
The first method uses program block, but this block in the calculation does not take into account the thyristor rectifier. For this reason, I have used another method for determining the frequency characteristics, which enabled me in the calculation consideration of thyristor rectifier. I have also compared both methods with each other.
For the determination of the contribution I also used three different methods. The first method is a harmonic vector method based on a network and customer input impedance determined at the point of common coupling.
Another method deals with what was harmonic distortion before and after connecting to the consumer. The difference in harmonic distortion before and after connecting the consumer is the consumer’s contribution to the overall distortion.
The third method is the same as the second, but it is based on reference impedances.
In conclusion, I commented and explained the obtained results. The results confirmed my previous expectations.
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