Voltage-Fed Three-Phase Semi-Dual Active Bridge DC–DC Converter Utilizing Varying Operating Modes With High Conversion Efficiency

Unified Fast-Dynamic Direct-Current Control Scheme for Intermediary Inductive AC-Link Isolated DC-DC Converters

“…Similarly, as shown in Fig. 18, a three-phase semi-dual active bridge dc-dc converter is presented for wide input variations and high voltage interface [37].…”

“…Generally, the unidirectional I 2 ACL dc-dc converter can be employed in some unidirectional applications such as PV and fuel cell systems [31][32][33][34][35][36][37][38][39][40][41]. The bidirectional I 2 ACL dc-dc converter can be used in some bidirectional applications such as energy storage systems and dc grid systems [20,[42][43][44][45][46][47][48][49][50][51][52][53].…”

“…Since the multi-level I 2 ACL isolated dc-dc converter can tolerate higher voltage, these converters can be suitable for some middle voltage applications [49,50]. Moreover, compared with the single-phase I 2 ACL isolated dcdc converter, the multi-phase I 2 ACL isolated dc-dc converter can provide a lower ripple current to the dc-link [37,46], so a lower dc-link capacitor can usually be adopted. Sometimes, multi-ports may be required for connecting several voltage sources, where the multi-winding I 2 converters can be used for high power density [20,41,53].…”

“…Moreover, by using the DAB dc-dc converter as an example for bidirectional I 2 ACL dc-dc converter, when the transferred power suddenly changes for addressing the disturbance of input voltage and load condition, the transient waveforms of Unidirectional: [31] Bidirectional: [42] Unidirectional: [32], [33], [35], [36] Bidirectional: [43], [44], [47], [48] Unidirectional: [38], [39], [40] Bidirectional: [38], [49], [50], [51] Unidirectional: [34], [37] Bidirectional: [45], [46], [52] Unidirectional: [41] Bidirectional: [20], [ As shown in Fig. 38, since the input voltage and the output voltage can be regarded as the same in a switching period, the transferred power PT of the DAB dc-dc converter can be calculated by the new phase-shift ratio D' as,…”

“…Then, the modulation method of this converter should be determined, and generally, the phase-shift modulation method is the most suitable modulation method for the I 2 ACL converter. Based on the employed phase-shift modulation method, the relationship between the transferred current and the phase-shift ratio should be determined, which can be usually found in the existing papers [20,22,30,37]. Moreover, to realize the proposed unified FDDC control scheme, the phase-shift ratio should be calculated by the transferred current, which can be employed to connect the outer-loop control value and the phase-shift ratio as shown in Fig.…”