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Abstract

This paper presents a management strategy of an isolated phase-shifted DC-DC buck converter (270V/28V, 5kW, 100kHz) used as a Li-ion battery charger for more electric aircraft. Three PI control loops are involved: An inner loop for the converter's output current, an outer loop for the battery charge current in case it is connected, and another outer loop for converter output voltage control when the battery is disconnected and only auxiliary LVDC loads need to be fed. The main contribution herein, is the control mode transition supervisor (CMTS) that communicates with the battery management system (BMS) through CAN and SCI interfaces, in order to safely switch between the control modes, depending on its presence on the network and its state of charge. Stability of the PI loops is guaranteed using Bode's stability criterion in frequency domain. Effectiveness of the proposed management strategy is verified through simulation and experimental validation.

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... To fulfil all the emission and fuel consumption requirements while also meeting those for aircraft safety, new architectures are needed. Currently, the most popular alternative that researchers are working on from a range of perspectives is the More Electric Aircraft (MEA) initiative [9,10,11,12]. Table 2 presents the main differences between traditional and the expected future aircraft. Table 2 demonstrates that electric systems will replace non-electrical ones in near future. ...
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