High-Power Three-Port Three-Phase Bidirectional DC-DC Converter

Abstract

Abstract-This paper proposes a three-port three-phase bidirectional dc-dc converter suitable for high-power applications. The converter combines a slow primary source and a fast storage to power a common load (e.g., an inverter). Since this type of system is gaining popularity in sustainable energy generation systems and electrical vehicles, the proposed topology is of practical interest. The proposed converter consists of three high-frequency inverter stages operating in a six-step mode, and a high-frequency three-port three-phase symmetrical transformer. The converter provides galvanic isolation and supports bidirectional power flow for all the three ports. An arbitrary power flow profile in the system can be achieved by phase shifting the three inverter stages. Thanks to the three-phase structure, the current handling capability of the circuit is larger and the ripple currents at the dc sides are much lower owing to the interleaving effect of the threephase, and thus the VA rating of the filter capacitors is much lower. The operating principle and, in particular, the transformer design which is based on conventionally and coaxially wound structures are presented. Circuit simulation results are included to verify the proposed converter topology and the dual-PI-loop control strategy.

A 80-kW Isolated DC–DC Converter for Railway Applications

“…Besides the lower VA ratings, the effective ripple frequency of the filter currents is three times higher, allowing to use smaller filters. Compared to the single-phase DAB, the currents through the transformer windings are much more sinusoidal, resulting in reduced highfrequency losses in the transformers [14]. A comprehensive comparison of single-phase and three-phase DAB topologies is given in [1], [15].…”

Examination for a symmetric-flux ferrite core for three-phase converter applications

“…The concept of such cores is not new [4], [9]- [14]; nevertheless the correct effective parameters analysis, techniques and cost of implementation hold back the use of those geometries.…”

Multiport converters for hybrid power sources

“…We have presented in [26] a three-port three-phase TAB converter topology (Fig. 11) which is an extension of the singlephase TAB topology.…”