There are some isolated dc-dc converters which have similar dynamic characteristics as the DAB dc-dc converter featuring the I2ACL configuration. However, the dynamic improvements of these I2ACL dc-dc converters are limited. Besides, the dynamic equivalenceDynamic equivalence between the DAB dc-dc converter and others I2ACL isolated dc-dc convertersI2ACL isolated dc-dc converter should be systematically revealed, which can be the precondition for extending the control scheme of the modular DAB dc-dc converter systems to other I2ACL dc-dc converters with the same configurations such as the IPOPIPOP, IIOPIIOP, IPOSIPOS and ISOP. Therefore, in this Chapter, the dynamic equivalenceDynamic equivalence among these I2ACL dc-dc converters is verified. Moreover, a unified FDDC scheme is proposed for boosting the dynamic responseDynamic response of these dc-dc converters when the input voltage and the load condition are changed.