Research On Central Air-conditioner Fuzzy Control System Based On Genetic Algorithm

With the rapid development of China,energy has become an important factor in the progress of the urbanization.Energy efficiency has caught the focus of social attention.In the background of Smart Community,it is easier to save energy by researching on the Central Air-conditioner chilled water system.This thesis studies the chilled water of Central Air-conditioner.The aim of this thesis is to design the controller of the chilled water system.The structure of Central Air-conditioner is complex and the Central Air-conditioner's energy loss is divided into the cooling load and the water system loss(the chilled water system loss and the cooling water system loss).The cooling load is usually fixed.So this thesis use a variable flow chilled water system to adapt to the cooling load of Central Air-conditioner.Because the structure of traditional PID control system is simple.So sometimes it might not reach a satisfactory control effect,especially facing with complex,nonlinear,time varying external environment.In this case,this thesis improves the control effect of traditional PID control system.In order to improve the control effect of chilled water system,this thesis combines fuzzy technology with the traditional PID control system.The task of fuzzy PID control system is to design the fuzzy controller.In the progress of designing the fuzzy controller,the main content is to select the membership functions and decide the fuzzy control rules.Using MATLAB to simulate the fuzzy controller,the result shows the difference of the fuzzy PID control system and the traditional PID control system.After comparing the results,the fuzzy PID control system's control effect has greatly improved.But there is still a small overshoot.In order to obtain the result of non-overshoot,the fuzzy controller's fuzzy rules are optimized by genetic algorithm.At last,this thesis gets a step response curve without overshoot.In the end,this thesis describes the Smart Community Central Air-conditioner monitoring system,describing the process of designing the Central Air-conditioner monitoring system and the main function of it.This Central Air-conditioner monitoring system uses the sensors to collect the parameters of the Central Air-conditioner,and then use parameters to analysis and control system.