Flexible Modification Technology and Application Prospect of Thermal Power Unit Based on High Temperature Molten Salt Heat Storage

[Introduction] Through the analysis of the exsiting problems in conventional flexibility modification technology of thermal power units, a new type of flexibility modification technology is proposed, which is to embed a large-capacity high-temperature molten salt heat storage system in the traditional "boiler-turbine" thermal system. It weakens the original rigid connection of boiler-turbine coupling to achieve deep peak regulation and flexible operation of thermal power units. [Method] According to the different thermal characteristics of steam, water and molten salt, an integrated thermal system of "boiler-high temperature heat storage-steam engine" was established by thermal balance calculation. [Result] The results show that the deep peak regulation capability of thermal power unit is greatly improved after configuring high-temperature molten salt heat storage system, and the problems of conventional modification methods can be solved. At the same time, the ability of the units to provide high-parameter industrial steam will be greatly improved. This will effectively improve the economic efficiency of power plants and make up for the lack of peak regulation compensation mechanism. High-temperature molten salt heat storage technology can also be applied to the life extension of thermal power plants, not only increasing the grid's flexible peak regulation power supply, but also enabling old power plant enterprise assets continue to create benefits. [Conclusion] After a batch of thermal power units in the grid are modified by large-scale high-temperature molten salt heat storage technology, a large number of flexible peak regulation power sources are provided for the grid, without increasing the total coal consumption and effectively alleviating the problem of new energy power consumption. Meanwhile, steam turbines and generators are reserved, which can provide backup capacity and moment of inertia for the power system, to ensure the safety and stability of the power supply and the grid. The promotion of this technology will effectively promote the upgrading of thermal power plants and help achieve the goal of "carbon neutrality and carbon peak"