Search

This paper proposes a modular isolated dc–dc converter, based on the input-series and output-series association of the full-bridge PWM dc–dc converter with capacitive filter. The main attribute of the proposed architecture is its ability to provide self-balance of the input and output voltages across the individual converters, without voltage loop control scheme, both in the steady-state and transient operations. Circuit operation, theoretical analysis, and modeling are included in this paper, along with experimental results taken from a laboratory prototype with four modules, 1600-Vdc total input voltage, 1600-Vdc total output voltage, 4-kW output power, and 40-kHz switching frequency. Possible applications include high-voltage power supplies, solid-state transformers, dc current distribution systems, and renewable electric energy systems. [ABSTRACT FROM PUBLISHER]

In this paper, a ZVS-PWM three-phase current-fed push–pull dc–dc converter is proposed. When compared to single-phase topologies, the three-phase dc–dc conversion increases the power density, uses the magnetic core of the transformer more efficiently, reduces the stress on switches, and requires smaller filters since the frequency for its design is higher. The proposed converter employs an active clamping technique by connecting the primary side of the transformer to a three-phase full bridge of switches and a clamping capacitor. This circuit allows the energy from the leakage inductances to be reused, increasing the efficiency of the converter. If appropriate parameters are chosen, soft-commutation of the switches (ZVS) can also be achieved. The soft-commutation improves the efficiency even further, allows higher switching frequencies to be used, and reduces the electromagnetic interference significantly. Applications such as fuel cell systems, transportation, and uninterruptable power supplies are some examples that can benefit from the advantages presented by this converter. The theoretical analysis, a design example, and the experimental results for a prototype implementing this topology are presented. The prototype was designed to process 4 kW at full load with an input voltage of 120 V, an output voltage of 400 V, and a switching frequency of 40 kHz. [ABSTRACT FROM PUBLISHER]

Automotive embedded electronic systems have been increasing in power and complexity and, therefore, more advanced power electronic converters are necessary in these vehicles. Several dual-voltage (42 V/14 V) bidirectional converter architectures have been proposed for automotive systems in recent years. However, most of them have low efficiency or are based in series and parallel configurations with large number of semiconductors and magnetics devices. Therefore, in this paper, we propose a bidirectional high-efficiency converter with lower number of components. This converter was created by merging a switched-capacitor converter and a conventional bidirectional converter, resulting in a hybrid topology. The voltage across the semiconductors of the proposed converter is equal to half of the highest voltage source value. Furthermore, the topology is composed of only one inductor to control the power flow between the two voltage sources. To verify all the mentioned features, a prototype was implemented experimentally, reaching a maximum efficiency of 97.5%. [ABSTRACT FROM PUBLISHER]