The Research Of Network And Control Technology In Solar Thermal Power Generation System

In recent years,great development has been made in the clean energy area all over the world.As a kind of abundant and cheap clean energy,the solar power has gradually begun to replace traditional fossil energy and will become the main energy source of human production in the future.Since 2011,solar power technology and related studies have been encouraged by the government.Through the continuous efforts of the enterprises and research institutions,our nation has a lead in solar power field at present.More and more attention has been paid to solar thermal technology because of its high photovoltaic conversion efficiency without any pollution.Solar thermal technology is more suitable for large-scale industrialization.What has improved the efficiency of the power grid and energy utilization is the Networked Control System consisting of many individual generators.For the study of the solar thermal system,it is important to improve the control accuracy and guarantee the communication stability.According to the dish solar thermal technology,a control system based on the Zig Bee technology is designed in this thesis.The Networked Control System is introduced into traditional control theory in this thesis.The performance of this control system is also studied and analyzed.The specific studies are described below:(1)The solar thermal technology,especially the dish solar thermal technology,is summarized in this thesis.The Zig Bee technology and the PID control technology are also introduced in detail.(2)In this thesis,fuzzy toolbox and some other modules in MATLAB Simulink are used to build traditional PID model and fuzzy PID model.An improved method based on the fuzzy PID model is proposed.Traditional PID control is widely used in industrial control technology,but it shows great instability in some complex situations with interference.The improved fuzzy PID control technology also solved the interference problems in traditional control system.(3)Based on the MATLAB True Time platform,this thesis set up a Zig Bee wireless control system and made simulations.We analyzed the performance of traditional PID control,fuzzy PID control and the improved fuzzy PID control under different network latencies and packet losses.It is concluded that the improved fuzzy PID control is better than traditional PID control in terms of anti-interference performance and resistance of time delay.The improved fuzzy PID control algorithm is more accurate than traditional PID control algorithm,so it is more suitable for dish solar thermal power generation system because of its high requirements for control accuracy.(4)According to the system's function requirements,we designed a control system for the dish solar thermal based on the TMS320F2812 and the communication chip CC2530.The hardware of the system mainly consists of the power circuit,the main CPU communication circuit,the dependent CPU circuit,wireless communication circuit,the excitation circuit and so on.(5)The software of the system is made up of the main CPU software and the dependent CPU software.The main CPU software mainly completes communication function,data forwarding and data analysis.And the dependent CPU software performs periodic task,including data acquisition and self-test.The dependent CPU software also completes the tracking and control task for heliostat using the improved fuzzy PID control algorithm.The experimental results show that the control signal and the time delay of the system with improved fuzzy PID control algorithm is much better than the system with the traditional fuzzy PID control algorithm.