Dynamic Simulation Of Molten Salt Loop In Solar Tower Thermal Power Plant

Concentrated solar power system,generate high temperature by reflecting or focusing sunlight,and delivers the heat with thermal oil or molten salt to the electric generator as a method of generate electricity,it's also called thermal solar power.The source of energy is solar power,so it is more efficiency and environmental-friendly when compared with other kinds of new energy.CSP system is made up of three parts,the heat collecting system,thermal transfer and storage system,and electric generating system.Heat collecting system includes the focusing heliostat and heat receiver.The thermal transfer and storage system is made up of pipes and thermal storage tanks,which can storage energy during the peak time of solar power to extend the working time of the system and increase the efficiency.The electric generating system is familiar with ordinary power plants,which generates vapor with steam generator to the turbine and finally transfer the energy into electricity.The purpose of this project is the modeling and dynamic simulation of a solar tower power plant,analyzing the existing tower power plants and simulate the dynamic characteristics of a 50 MWe power plant,and evaluate the parameters of the system with the simulation result,then figure out the relationship between its efficiency and the working condition,concludes it dynamic characteristics,to make sure that is it feasible in engineering.And program a control system to make the system can function stably,to provide theory for the CSP plant operating.The work of this paper includes:1.Modeling the molten salt loop of solar power tower plant,which includes heat receiver,heat exchanger and the storage tanks,with Modelica language,and calculate the parameters such as temperature,velocity and mass flow rate to confirm that these parameters are in designed range and these parts can work properly.2.Develop a control system for the molten salt loop system,and make different operating policy for different working condition,to make sure that the system can work regularly and change the working condition automatically without human operating,and it is also important to make sure that it will not cause an accident or be out of the designed working conditions.3.Simulate the dynamic response of the whole system,analyze its dynamic characteristics and efficiency,to provide theory base for the engineer or commercial operating of the solar tower power plant.This article concludes the dynamic characteristics of the molten salt loop in a tower CSP plant,and designed a corresponding control system to ensure it stability.at last,simulated it response with solar direct normal intensity data in reality,validated that it can keep a high efficiency and extend working time under low solar direct intensity,gave some proposal to the energy storage system and energy system combination.