Model Predictive Control Structure for Proactive Voltage/Current Sharing of Modular Converters in Submarine Power Supply System

The submarine power supply system (SPSS) remains a critical device in the seafloor observation network (SON), which usually consists of multiple sets of DC/DC modules in series or parallel to achieve high-voltage, medium-voltage, and low-voltage power conversion. Thus, it is necessary to control the output voltage/current of each module and proactively distribute the electrical stress, extending the life cycle of the whole system. This paper mainly proposes a novel model predictive control (MPC) structure for proactive voltage/current sharing of modular converters in SPSS. Initially, the submarine DC power supply system, which consists of combined DC/DC converters, is discussed. Then, a finite control set MPC control framework is established when DC/DC modules are in the IPOS, ISOP, and IPOP structures of SPSS, respectively. Besides, the current sharing scheme of LLC resonant converters is derived detailedly. Finally, the further prospect of the proposed control method in SPSS of SON is discussed in detail. The proposed MPC control structure can significantly contribute to achieving long-term, high-reliability, and high-quality submarine power supply in SON.