The current coal-fired unit coupled with molten salt heat storage system technology has the problems of limited peak shifting capacity and poor peak heat economy. To address these issues

a new system of coal-fired unit coupled with compressed steam and molten salt heat storage is proposed

specifically including single molten salt heat storage scheme and double-molten-salt-heat-storage scheme. The system performs multi-stage compression of extracted steam through a multi-stage compressor and uses molten salt for heat storage. The compressed steam is eventually condensed to water so that its latent heat of condensation will be utilized. The simulation model of the coupled system scheme is established by EBSILON software. The research results indicate that

compared with the conventional molten salt heat storage technology scheme

the compressed steam and molten salt heat storage system can effectively reduce the effect of steam extraction and heat storage on the thermal economy of the system

and expand the peaking range of the unit. Specifically

the round-trip efficiencies of the single molten salt and doublemolten-salt scheme are improved from 27.43%～38.03% to 62.13%～64.56% and 65.69%～66.93%

respectively

and the minimum outputs are reduced from 20.91%Pe to 19.84%Pe and 19.28%Pe

respectively

compared with the conventional scheme. Considering the thermodynamic and economic performance of the system

the single molten salt scheme is the best choice.