The UK Government has set an ambitious target to achieve 15% of final energy consumption from renewable sources by 2020. High Voltage Direct Current (HVDC) technology is an attractive solution for integrating offshore wind power farms farther from the coast. In the near future, more windfarms are likely to be connected to the UK grid using HVDC links. With the onset of this fairly new technology, new challenges are inevitable. This research is undertaken to help assist with these challenges by looking at possibilities of problems with respect to faster AC/DC interaction modes, especially, on the impact of inrush currents which occur during fault-recovery transients. In addition to that, possible mitigation strategies are also investigated. Initially, the relative merits of different transformer models are analysed with respect to inrush current transient studies. The most appropriate transformer model is selected and further validated using field measurement data. A detailed electro-magnetic-transient (EMT) model of a grid-connected MMC-HVDC system is prepared in PSCAD/EMTDC to capture the key dynamics of fault-recovery transformer inrush currents. It is shown that the transformer in an MMC system can evoke inrush currents during fault recovery, and cause transient interactions with the converter and the rest of the system, which should not be neglected. It is shown for the first time through a detailed dynamic analysis that if the current sensors of the inner-current control loops are placed at the converter-side of the transformer instead of the grid-side, the inrush currents will mainly flow from the grid and decay faster. This is suggested as a basic remedial action to protect the converter from inrush currents. Afterwards, analytical calculations of peak flux-linkage magnitude in each phase, following a voltage-sag recovery transient, are derived and verified. The effects of zero-sequence currents and fault resistance on the peak flux linkage magnitude are systematically explained. A zero-sequence-current suppression controller is also proposed. A detailed study is carried out to assess the key factors that affect the maximum peak flux-linkage and magnetisation-current magnitudes, especially with regard to fault specific factors such as fault inception angle, duration and fault-current attenuation. Subsequently, the relative merits of a prior-art inrush current mitigation strategy and its implementation challenges in a grid-connected MMC converter are analysed. It is shown that the feedforward based auxiliary flux-offset compensation scheme, as incorporated in the particular strategy, need to be modified with a feedback control technique, to alleviate the major drawbacks identified. Following that, eight different feedback based control schemes are devised, and a detailed dynamic and transient analysis is carried out to find the best control scheme. The relative merits of the identified control scheme and its implementation challenges in a MMC converter are also analysed. Finally, a detailed EMT model of an islanded MMC-HVDC system is implemented in PSCAD/EMTDC and the impacts of fault-recovery inrush currents are analysed. For that, initially, a MMC control scheme is devised in the synchronous reference frame and its controllers are systematically tuned. To obtain an improved performance, an equivalent control scheme is derived in the stationary reference frame with Proportional-Resonant controllers, and incorporated in the EMT model. Following that, two novel inrush current mitigation strategies are proposed, with the support of analytical equations, and verified.

Le Pow-wow de Kanasatake a vu le jour en 1991, après l’évènement marquant de la Crise d’Oka. À la suite de ce conflit, l’objectif initial consistait en une tentative de réconciliation et le maintien d’une bonne entente entre les membres de la communauté autochtone et les non-membres, appelés « allochtones », résidant sur le terrain voisin de leur territoire dans la municipalité d’Oka. L’objectif de la recherche est de savoir en quoi un événement de pow-wow comme celui de Kanesatake et les performances de danse qui y sont présentées peuvent mener à la guérison chez les artistes autochtones qui y participent. Pour y parvenir, je me suis entretenu avec des artistes pratiquant la danse traditionnelle, également participants au Pow-wow de 2018 et 2019, afin de connaître leur cheminement personnel et leurs perceptions en lien avec leur propre spiritualité, ainsi que les facteurs extérieurs et historiques ayant pu influencer leurs pratiques artistiques. Au fil des entrevues, la notion de guérison psychique, physique et collective est ressortie dans plusieurs réponses données par les participants. Nous verrons aussi plus en détail les liens unissant les tenues traditionnelles, les danses et les rythmes musicaux. Nous ferons aussi référence à l’événement de la « Rencontre internationale d’art performance autochtone » (RIAPA) s’inscrivant davantage dans une contemporanéité pour dénoter une certaine continuité entre ces deux événements. / Kanasatake's Pow-wow was born in 1991, following the landmark event of the "Oka Crisis". As a result of this conflict, the initial objective was an attempt at reconciliation and the maintenance of good understanding between members of the Aboriginal community and the non-members, also known as "allochtones" residing on land adjacent to their territory in the municipality of Oka. The purpose of this master thesis is to understand how a pow-wow event like Kanesatake's and the dance performances presented there can be a healing factor for Aboriginal artists. To achieve this, we spoke with traditional dancers, participants in the 2018 and 2019 Pow-wow, to learn about their personal journeys and perceptions of their own spirituality, as well as the external and historical factors that may have influenced their artistic practices. Over the course of the interviews, the notion of psychic, physical and collective healing was reiterated in several responses given by participants. We will also see in more detail the links surrounding traditional outfits, dances and musical rhythms. We will also refer to the “International Meeting of Aboriginal Performance Art” event (RIAPA), which is more in a contemporaneity to indicate a certain continuity between these two events.

Im Mai 2010 begab sich eine Studiengruppe in das Land Niedersachsen, um nach den Spuren polnischer Migranten zu suchen, die sich im Zweiten Weltkrieg und unmittelbar danach in Nordwestdeutschland aufgehalten haben. Es handelte sich dabei um Feldforschung zur Geschichte der Polen, die infolge des Untergrundkampfes während der deutschen Okkupation sowie einer aktiven Beteiligung am Warschauer Aufstand verhaftet und in die Kriegsgefangenenlager sowie Arbeitslager verschleppt wurden. Die Frage nach ihrem Schicksal während und nach dem Krieg hat die Studenten aus Deutschland und Polen begleitet. Besichtigt wurden Originalschauplätze in Niedersachen, besonders im Emsland, darunter Kriegsgräberstätten sowie einige Orte, wo einst Kriegsgefangenenlager gestanden haben. Auch der Stadt Haren, wo sich 1945-1948 das Zentrum der Polnischen Besatzungszone befand, wurde ein Besuch abgestattet. Das Band enthält studentische Beiträge mit Vorwort von Prof. Dr. Zdzisław Krasnodębski. / In May 2010, a study group went into the Land of Lower Saxony to search for traces of Polish migrants in the Second World War, who have been imprisoned in northwest Germany. This was a field research on the history of Poles, who fought during the German occupation among other as active participants in the Warsaw Uprising. The question of their fate during and after the war accompanied the students from Germany and Poland. The original sites in Lower Saxony, particularly in Emsland were visited, including cemeteries and some places where once the POW camps have stood. We visited also the city Haren, where 1945-1948 was the center of Polish occupation zone. The volume contains student’s entries with a foreword by Prof. Dr. Zdzisław Krasnodębski.

About 3850 men of the First Australian Imperial Force were captured on the Western Front in France and Belgium between April 1916 and November 1918. They were mentioned only briefly in the volumes of the Official Histories, and have been overlooked in many subsequent works on Australia and the First World War. Material in the Australian War Memorial has been used to address aspects of the experiences of these neglected men, in particular the Statements that some of them completed after their release This thesis will investigate how their experiences ran counter to the narratives of CEW Bean and others, and seeks to give them their place in Australia???s Twentieth Century experience of war.

About 3850 men of the First Australian Imperial Force were captured on the Western Front in France and Belgium between April 1916 and November 1918. They were mentioned only briefly in the volumes of the Official Histories, and have been overlooked in many subsequent works on Australia and the First World War. Material in the Australian War Memorial has been used to address aspects of the experiences of these neglected men, in particular the Statements that some of them completed after their release This thesis will investigate how their experiences ran counter to the narratives of CEW Bean and others, and seeks to give them their place in Australia???s Twentieth Century experience of war.

This thesis examines the legal case of Inouye Kanao, a second-generation Japanese Canadian who was executed for high treason in August 1947 in Hong Kong. In this thesis, I trace not only Inouye's legal case, but also his early life, the broader political context, diplomatic correspondence, and other war crimes cases. By employing race-thinking and Critical Race Theory as theoretical frameworks, I consider the role of race and racism and aim to better understand its influence on Inouye's legal case. In doing so, this thesis challenges previous narratives and misinformation about Inouye. I conclude that racism was a significant factor that affected all aspects of Inouye's case, resulting in an unjust execution that did not reflect the crimes. Ultimately, Inouye was executed not because of his actions but because he was racialized as a treacherous and cruel Japanese Canadian. / Graduate

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