Search

This paper describes a modular architecture based on the dual-active bridge (DAB) converter in input-series–output-parallel (ISOP) connection. This work is focused on the input voltage sharing to ensure a proper operation of each module by means of an active control of input and output voltages. A small-signal model of the modular architecture is proposed and a decoupled control loops’ scheme is used to implement the control strategy. An experimental setup has been built in order to validate the model of the DAB converter in ISOP connection and the proposed control strategy, taking different operating conditions and constructive parameter values into account. [ABSTRACT FROM AUTHOR]

This paper addresses the performance of the bidirectional dual active bridge (DAB) converter. One of the advantages of the DAB is the possibility to achieve the zero-voltage switching (ZVS) operation in all the switches of this converter. However, the ZVS operation range can be lost for light loads, especially if high voltage is required in at least one of the DAB ports and the phase-shift control is used to regulate the power processed by the converter. Theoretically simple averaged and small-signal models are presented for the DAB converter. Using the study presented in this paper, the boundaries of the ZVS operation can be easily evaluated. The proposed models and analysis of the ZVS boundaries allow the proposal and evaluation of two different design strategies with different purposes: on the one hand, increasing the ZVS operation range and, on the other, improving efficiency at full load. Moreover, some techniques are presented for increasing the ZVS operation range and improving the efficiency of the DAB at full load (both using phase-shift control) employing the aforementioned analysis to obtain certain design criteria and conclusions. Finally, the proposed models, design strategies, and techniques to improve the performance of the DAB are experimentally tested using a 1-kW prototype with input and output voltages of 48 and 400 V, respectively. [ABSTRACT FROM AUTHOR]