Theoretical And Experimental Analysis Of Heliostat Control Strategies And Methods

Heliostat is the core concentrating device in the solar power tower plant,and its stable running guarantees the efficient operation of the power station.However,how to operate with high precision and stability in a harsh environment has always been a major engineering problem.Generally,it is indispensable to correct heliostats,but the data measurement in the process of correction would be difficult.This thesis has carried out related theoretical and experimental researches.In these researches through the solar position modeling,the heliostat control method,the spot processing model,the data measurement method,correction models,and correction strategies,the model design and experiment of the whole process of heliostat correction have been completed.Main research contents and innovations of this thesis are as follows:(1)A set of heliostat correction experimental system is built.The main equipments includes a two-axis platform driven by stepper motors,a local controller based on PLC,a mirror with fine curvature,a CCD camera and a laptop supporting the environment of Matlab software.With the help of the methods,models and equipments,a software is designed to realize the automated collection of experimental data.(2)A set of the space vector fitting measurement method is proposed,whose feasibility is verified by the theoretical and experimental method respectively.(3)The heliostat correction geometric model is established.Based on the measured data,the correction verification experiment is carried out to verify the correctness of the geometric model.(4)A special-shaped heliostat integrated with a sun-positon sensor has been designed and built,and its feasibility is verified by the error analysis.