Study of power conversion system for Chinese Fusion Engineering Testing Reactor

Fusion energy is a promising manner in the future clean power industry for practical application. This paper presents an exploratory analysis of applicability of Supercritical Carbon Dioxide (S–CO2) Brayton Cycle for Power Conversion System (PCS) of Chinese Fusion Engineering Testing Reactor (CFETR) compared with Steam Rankine cycle and Helium Brayton Cycle. It is proved that S–CO2 Brayton Cycle is suitable for PCS of CFETR, with the advantages of compactness and high cycle efficiency. The different heat sources which include blanket (BNK) and divertor (DIV) in the first cooled circuit are taken into account. A new S–CO2 Brayton Cycle layout with DIV is proposed. The results show that adding the DIV heat source indeed improves the cycle efficiency from 30.5% to 34.7%. In addition, efficiency optimization of S–CO2 Brayton Cycle with pressure ratio, turbine inlet temperature, the length of low temperature recuperator and pre-cooler has been carried out based on the present blanket design of CFETR. The maximum efficiency and optimal parameters are obtained. •Different power conversion systems for CFETR are designed and compared.•A new S–CO2 Brayton cycle layout is proposed for blanket and divertor under CFETR.•Heat exchangers of S–CO2 are modeled and programmed to study their characteristics.•An optimization of S–CO2 Brayton cycle is obtained for high efficiency under CFETR.