The More Electrical Aircraft concept requires electronic devices able to efficiently and safely convert electrical power between different voltage levels. The entire realization of a bidirectional DC/DC converter, from design to validation phase, is here discussed in detail. First, a boost full bridge electrical structure is selected, adopting a Parallel Input Parallel Output (PIPO) interleaving technique and an optimal turns ratio selection for the transformers in order to reduce both weight and size of the equipment. Next, modulation schemes in both step-down and step-up modes are discussed. Successively ad hoc PI regulators for both operative modes are presented. A key idea of the paper is that the converter behavior must be related not only to the control strategy but also to a global supervision logic able to safely conduct the converter operations and to react from external stimuli. Thus, a finite state machine (FSM) approach is employed. An innovative strategy called buffer mode is presented, defined as an intelligent combination of buck and boost modes. Extensive simulations and experimental results are shown, in order to confirm the effectiveness of the proposed approach. 1. Introduction Classical onboard aircraft systems use different power sources: mechanical, electrical, hydraulic, and pneumatic. To overcome the classical drawbacks of nonelectrical or only partially electrical equipment, the More Electrical Aircraft (MEA) concept has been introduced, having as target the use of electrical power sources only. This strategy has some advantages as follows:(i)higher reliability;(ii)ease of maintenance;(iii)lower consumption of fuel;(iv)lower production costs and maintenance. An immediate consequence of this new approach is the necessity of electrical power sources, distribution, and sharing of the power redesign phase, in order to accommodate for new technologies insertion inside classical aircraft systems. To limit the section area of the electrical power conductor and to simplify the dynamical connection/disconnection of one or more power generators (without necessity of synchronization as for AC sources), the MEA’s study [1] suggests to use as main bus a high-voltage DC bus. The new standards assume ±270？VDC or +270？VDC for the main bus and 28？VDC, 115？VAC@400？Hz, and 230？VAC@400？Hz for secondary bus. As a result, in modern aircraft different kinds of power electronic converters, such as AC/DC rectifiers, DC/AC inverters, and DC/DC choppers, are required. In particular, bidirectional DC/DC converters are used in battery charge/discharge units
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