Research on start-up control strategy of S-CO₂ recompression cycle power generation system

Abstract

To ensure both safety and rapidity in the start-up process of the supercritical carbon dioxide (S-CO₂) power generation system, this paper proposes a two-stage hot start-up control strategy (SUCS) for a 600 MW S-CO₂ recompression cycle power generation system (SCRCPGS). The two stages respectively utilize a valve and inventory combined load control strategy and a turbine inlet temperature change load control strategy to achieve the goal. Moreover, an implementation plan for the sequential cold start of each system equipment is proposed. By applying the SUCS proposed in this paper, the start-up process of the 600 MW SCRCPGS was realized. The safety indicators of the system start-up process, including the compressor surge margin, the minimum flow rate of the heater, the rate of change of the pipe wall temperature, and the high and low pressure of the working medium, were verified, and all safety indicators were met. The start-up process took 1.09 hours, which was 0.57 hours shorter than that in the reference, proving the rationality and effectiveness of the SUCS designed in this paper.