Research on autonomous decision-making technology for once-through steam generator

•In this paper, the innovative research of the autonomous control system of the once-through steam generator (OTSG) is carried out, which is mainly aimed at the normal operating condition, especially the fault condition when the operating characteristics of the system change dramatically.•The ISSA algorithm is applied in the research of autonomous decision-making modules because of its strong ability of optimization and fast convergence.•This paper improves the SSA algorithm from two aspects: population initialization and finder position update and the optimization ability. In this paper, the innovative research of the autonomous control system of the once-through steam generator (OTSG) is carried out, which is mainly aimed at the normal operating condition, especially the fault condition when the operating characteristics of the system change dramatically. The autonomous control system includes fault diagnosis, autonomous decision-making, hybrid control modules. The ISSA algorithm is applied in the research of autonomous decision-making modules because of its strong ability of optimization and fast convergence. This paper improves the SSA algorithm from two aspects: population initialization and finder position update and the optimization ability. The simulation results show that the autonomous control system proposed in this paper can make a decision in the shortest possible time, and provide an effective automatic control method to make the OTSG quickly and smoothly reach the safe state.