This thesis presents the design, implementation, and experimental testing of a single-phase
bidirectional DC-DC converter based on the dual active bridge (DAB) topology. The main
objective was to evaluate the performance of the implemented converter and investigate the
behavior of SiC MOSFETs in the circuit.
The first part of the thesis describes the general circuit topology and the design of the
transformer and series inductor, which form the high-frequency link between the low-voltage
and high-voltage sides of the converter. It then presents the circuit design and component
selection. The converter is divided into four main sections: the power stage, comprising two
transistor bridges; the gate-drive stage; the auxiliary power-supply section, comprising DC-DC
converters and voltage regulators; and the measurement section, comprising voltage and current
sensing circuits.
The final part presents the experimental procedure and measurement results, with emphasis on
the power transfer and efficiency characteristics at the highest safely tested voltage levels:
250 V on the high-voltage side and 30 V on the low-voltage side. Communication interruptions
between the PC and the microcontroller occurred during tests with high-side voltages from 100
to 250 V. At voltage levels above 250 V/30 V, further testing was limited by the thermal
performance of the low-voltage stage. Within the practical operating range, the measured
efficiency ranged from 86% to 96%.
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