[en] Aiming to reduce the pollution caused by the traditional aircraft, strong research efforts are done towards the aircraft electrification to reduce the fuel usage. Thus, high efficiency, high power density and high reliability are some of the main characteristics expected from the future More Electric Aircraft (MEA), among others. In this context, the development of a High Voltage Direct Current (HVDC)-based aircraft distribution grid with bidirectional power flow capability results an interesting alternative to increase the distribution efficiency, reduce cable weight and provide bidirectional power-flow capability. This PhD thesis focuses on replacing the conventional passive AC/DC converters for a highefficient, high-power-dense, fault-tolerant and bidirectional active modular rectifier architecture which enhances the implementation of a HVDC primary distribution-based MEA Electric Power System (EPS). For that purpose, the potential active AC/DC topologies for the defined application are reviewed and their suitability in MEA applications has been studied. Afterwards, a topology evaluation is performed aiming to find the most suitable active AC/DC topology. Based on the comparison results, three converter configurations are proposed which are used for designing three different active modular architecture which comply with the aviation standards. The three architectures are then compared in terms of efficiency, power density and reliability aiming to identify the most promising solution. Finally, the resulting active modular architecture is integrated into the MEA power system to study its fault-tolerant capability. Thus, two different power system topologies are evaluated considering the integration of the active modular architecture with a proposed comparison methodology focused on efficiency, weight, survivability and fault clearing speed.

[eu] Ohiko hegazkinek eragindako igorpenak murrizteko helburuarekin, ikerketak egiten ari dira hegazkinen elektrifikazioaren alorrean, hegazkinek erregai gutxiago erabil dezaten. Horrela, asmoa da etorkizuneko Hegazkin Elektrikoagoak (MEA) efizientzia handia, potentzia dentsitate handia eta fidagarritasun handia edukitzea ezaugarri bereizgarri gisa. Testuinguru horretan, proposatzen da HVDC banaketan oinarritutako sistema elektriko bat garatzea, banaketan efizienteagoa izateko, guztirako pisua murrizteko eta ezaugarri gehigarriak - bi norabideko potentzia fluxua, esaterako - emateko aukera gisa. Doktore tesi honen ardatza da AC/DC bihurgailu pasibo tradizionalaren ordez bihurgailu modular aktiboen arkitektura bat jartzea, HVDC banaketa sare bat ezarri ahal izateko eta efizientzia handia eta potentzia dentsitate handia eskaintzeko, gabeziak jasateko gai izateaz gain. Horretarako, AC/DC bihurgailu aktiboen topologiak berrikusi dira eta MEA aplikazioen testuinguruan duten bideragarritasuna aztertu da. Ondoren, konparaziorako azterketa bat egin da, hobekien egokitzen den AC/DC topologia aurkitzeko. Konparazioaren emaitzetatik abiatuta, bihurgailuaren hiru konfigurazio desberdin proposatu dira, eta horiekin MEAren araudiari heltzen dioten hiru arkitektura modular diseinatu dira. Behin diseinatuta, hiru arkitektura horiek alderatu egiten dira aplikaziorako soluziorik egokiena aurkitzeko. Azkenik, bihurgailu aktiboen arkitektura MEAren HVDC sistema elektrikoan txertatzen da, gabeziak jasateko duen gaitasuna aztertzeko. Horrela, bi sistema elektrikori buruzko azterketa konparatiboa proposatu da, biek arkitektura modular aktiboa integratuta dutela kontuan hartuta. Konparazioan proposatutako metodologia, azkenik, eraginkortasunaren, pisuaren, bizirauteko gaitasunaren eta gabezien ebakuazio abiaduraren emaitzak alderatzean oinarritzen da.