Design Optimization Of 100MW Molten Salt Solar Thermal Power Tower Plant

Solar thermal power tower plant technology is rapidly advancing due to its unique advantages.The technology will be developed in the direction of large-scale molten salt absorption,heat storage and large-scale high-parameter single tower.At present,its initial investment is large,and the instability and intermittentness of solar radiation also bring high requirements to the operation process of stable grid-connected power generation.Therefore,it is of great significance to optimize the design of the system.In this paper,the advantages and disadvantages of four types of solar thermal power generation technologies,such as trough,tower,dish and linear Fresnel,are compared,and the solar thermal power tower plant system is decomposed and analyzed.A new type of heliostat field arrangement combining dense arrangement and staggered arrangement is defined.The subsystem model and AspenPlus process model were built for a 100MW molten salt solar thermal power tower plant by sequential module method,and the equipment operation status of the system under different load conditions under TMCR conditions was simulated.Visual C#was used to develop a tower-type photothermal power station optimization design software with a good interactive interface.Calculated and analyzed the influence of the tower height(180~280m),the design point DNI value(800~1200W/m~2),the solar multiple(1.8~2.6)and the heat storage hours(5~14h)on the thermal performance of the system.The new heliostat field arrangement can increase the heliostat field efficiency by 2.4%,reduce the number of heliostats by about 1000,and reduce the LCOE by 10.63%.The DNI value of the design point under the same solar multiple and heat storage time has a great influence on the number of heliostats,and has little effect on the heliostat field efficiency and photothermal conversion efficiency,depending on the local climatic conditions.The tower height of the endothermic tower is limited by the actual production level,and as the tower height increases,the trend of increasing the efficiency of the mirror field changes,and the trend of increasing cost gradually becomes larger.Increasing the solar multiple in a certain range can increase the heat collection and power generation,but it will be limited by the investment and heat storage capacity,and the trend of increasing power generation will gradually slow down.Under the arrangement of the new heliostat field,the optimal design parameters of the research object are the design point DNI value of 900W/m2,the solar multiple of 2.6,the heat storage time of 12h,and the tower height of 238m.Compared with the existing software SAM,the results show that the built system model can reflect the system characteristics faster and more accurately.The performance evaluation model of solar thermal power tower plant system developed in this paper can provide theoretical support for design optimization and performance optimization of the whole system,and it has certain engineering practical value in practical application.