The following work compares the results of a 2D magnetostatic analysis using a finite element method with a 3D analysis of the same electromagnetic structures. The thesis shows that a 3D analysis is much more accurate than a 2D analysis, with the exception of axially symmetrical 2D models, where the end result is very close to that obtained by 3D model analysis. The main factor influencing the difference in the results is the thickness of the air gap which is explained in Chapter 3. Therefore thesis concludes that the use of 2D analysis makes more sense in cases where the air gap is smaller. Chapter 4 compares 2D analysis with analytical calculation using a magnetic circuit. Also here the air gap plays a key role in the accuracy of the end result. This chapter also highlights the importance of using formulas to account for the fringing flux effect of the air gap, while also presenting new one as an alternative to those found in the literature. Chapter 5 compares short circuit impedances calculated with 2D and 3D models with measurement results. Finally, chapter 6 presents a special example of axially symmetrical 2D models, where 2D analysis turns out to be equivalent to 3D in accuracy.
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