Abstract: The output parallel dual active bridge (DAB) DC-DC converter has many advantages such as electrical isolation, high voltage regulation ratio, bidirectional energy transmission, and simple modular expansion; and thus has been widely concerned in recent years. Firstly, the typical control schemes of the power balance of parallel DAB converter were analyzed and summarized, the strategies under different schemes were combed in detail, and compared from the perspective of dynamic response, modularity, and the number of sensors. Furthermore, based on the efficiency and dynamic performance optimization methods of DAB, from the perspective of multi-module parallel connection, some typical hybrid optimization control strategies combining power balance control and DAB converter optimization were analyzed. Then, from the engineering point of view, other derivative ideas of the hybrid control strategy and the actual factors to be considered when selecting the control strategy were given. Finally, the fault-tolerant control scheme of output parallel DAB converter is summarized in detail from the switch, bridge arm, module, and topology.