The doctoral thesis focuses on solving some of the existing challenges in magnetic structures used for magnetic refrigeration. The magnetic structures of conceptual magnetocaloric cooling devices represent the heaviest and most expensive part of the device. Current devices operate at low frequencies and low power densities. Therefore, this work is aimed at designing and researching concepts that enable static operation with high energy efficiency and high power density. In the first part, various concepts of magnetic structures were designed, analytically and numerically analyzed through multi-parameter analysis of their performance. The selected concept was constructed, and an experimental setup was developed to evaluate the performance of the magnetic structure. In the following, different designs with active cooling of the windings were developed to reduce its temperature, thereby reducing heat transfer from the magnetic structure to the air gap. The chosen concept was constructed, and an experimental setup was established. The results of numerical and experimental evaluations show an improvement in the compactness of the magnetic structure compared to previously developed electromagnetic structures. Permanent magnets in an electro-permanent magnetic structure can generate part of the magnetic flux that would otherwise be generated by an electromagnet. This allows electro-permanent magnetic structures to operate with higher energy efficiency than only electromagnetic structures. The findings in this doctoral thesis are not limited to the field of magnetocaloric refrigeration but are also broadly applicable to the design of new electro(-permanent) magnetic structures.
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