## 4 Power Converter Topologies
### Charger Stage (Bidirectional DC-DC Converters)
#### 4.3.2 Isolated Charger Topologies
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Ref.** &
\begin{tabular}{c} **Charger** \\ **Topologies** \\ \end{tabular} & **Advantages** & **Disadvantages** & **Applications** \\ \hline \multirow{8}{*}{[13, 38, 77]} & & \(\bullet\) & By using substeps capacitors, & Higher switching & \(\bullet\) & High voltage applications \\  & ZVS DAB & & ZVS mode can only be achieved & turn-off losses & \(\bullet\) & High level of \\  & Converter & \(\bullet\) & It has low switching losses & \(\bullet\) & ZCS mode is not enabled & \\ \hline \multirow{8}{*}{[17, 34, 80, 81]} & & \(\bullet\) & Primary switches & \(\bullet\) & High voltage stress on & \\  & & \(\bullet\) & require soft-switching & the rectifier bridge & & \\  & & \(\bullet\) & Simple control & \(\bullet\) & Hard switching losses & \\  & & \(\bullet\) & The freewheeling interval & and the loss of & & \\  & Phase-Shift FB & & possess high current flow & guarantee with ZVT & \\  & Converter & \(\bullet\) & Achieve higher efficiency that & operation are & & \\  & Converter & \(\bullet\) & conventional FB topologies & consequences of PHEV & \\  & & \(\bullet\) & The PWM control reduce & current requirements & \\  & & \(\bullet\) & switching losses and current & dropping below & \\  & & & stress on devices & minimum critical & \\ \hline \multirow{8}{*}{[22, 34, 78, 82, 83, 84]} & & \(\bullet\) & It can achieve high efficiency in a full range of ZVS for primary switches, in high voltage operations and at the resonant frequency & \(\bullet\) & The transformer and filter designs & \\  & & & & & \\  & Converter & \(\bullet\) & No reverse recovery current in addition to an absent oscillation & \(\bullet\) & Ours the battery is low, its operation is & \\  & & & \(\bullet\) & The output voltage is able to be regulated during the & & \\  & & & & & \\  & & & hold-up time & & \\ \hline \multirow{8}{*}{[22, 79]} & & \(\bullet\) & The diode rectifier ringing is minimized inherently on the current fed topologies with capacitive output filter & \(\bullet\) & Has reverse recovery losses in the secondary rectifier diodes & \\  & Output Filter & \(\bullet\) & At ZVS mode can achieve high efficiency (approx. 95.7\%) & \(\bullet\) & Has high voltage ringing & \\ \hline \multirow{8}{*}{[22, 79]} & & \(\bullet\) & For bidirectional operation, the antiparallel diodes and & & \\  & & MOSFETs are used on both sides & & & \\  & & of the transformer & & & \\  & & \(\bullet\) & As a result of the two MOSFETs & & \\  & & connected in parallel on the & & \\  & & secondary side, there was a reduction in conduction losses & & & \\  & & Providies isolation as required by & & \\  & & the EV charging standards & & & \\  & & & & \\  & Four Interleaved & \(\bullet\) & Use less switches than the DAB & & \\  & Flyback Converter & and resonant & transformer used & & \\  & & converter topologies & & The topology is & \\  & & & In both charging and V2G & & \\  & & operation a quasi-resonance & & \\  & & & (QR) mode is operated & & \\  & & & Cause a reduction in turn-on & & \\  & & losses resulting from low-voltage & & \\  & & switching (LVS) or ZVS & & \\  & & & Turn-off losses approach zero, & \\  & & because resonant capacitors & & \\  & & & absorb turn-off energy & \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Comparison of isolated bidirectional DC-DC converter topologies. Figure 9: Schematic diagram of isolated bidirectional DC-DC topologies. (**a**) ZVS DAB converter; (**b**) phase-shift FB converter; (**c**) FB LLC resonant converter; (**d**) ZVS FB converter with capacitive output filter; (**e**) four interleaved flyback convert [13, 17, 78, 79, 38].