This paper proposed a novel dual input series output independent (ISOI) combined converter system. The system is suitable for providing energy for distributed independent energy storage batteries or distributed server system. While the input side of the converter is under high voltage conditions. In the system, the first level ISOI system is power ISOI system. The power ISOI system consists of two identical converters while they are connected in series at the input side. The output side of the two power converters are connected to separate batteries or servers to provide power for them. Therefore, the system can effectively reduce the input voltage withstand of each converter, and improve its reliability and modularity. The second level ISOI system is auxiliary ISOI power supply system. In this system, the two converters are connected in series, while their output provides power to control circuits of the two power converters respectively. Due to the modular approach adopted by both power and auxiliary converters, the degree of modularization and reliability of the entire system has been effectively improved. Further, a dual common duty cycle control method is carried out to achieve input voltage sharing (IVS) of the power converters and each module of the auxiliary converters. The proposed system is introduced and modelled. The controller is designed. The prototype is carried out to analyze the performance of the system.