Research And Engineering Practice On Fuzzy-Adaptive PID Controller For Air-conditioning System

As an import part of intelligent building system,air-conditioning system plays a more and more important role in it with the development of intelligent technology.Traditional air-conditioning systems have the drawback of high energy consumption and low efficiency.With the aggravate of energy critical,energy conservation becomes an important task.To solve the problem that the air-conditioning system has the drawback above,the main scheme and design of control system is designed based on the two engineering projects in Yanjiao logistics city and Chuigezhuang.Mathematical model of air-conditioning system is constructed and the Fuzzy-adaptive PID controller is designed.The main works of this paper comes as the follows:Firstly,an analysis on the operation principle of each part of air conditioning system is presented,in which a frame of the air conditioning system is constructed.Based on the presented principle,math models are presented of each part of the air conditioning system via physics and math methods,including the surface cooler,silencer,filter and so on.The resistance of wind and water in the air conditioning system is analyzed in which micro analysis on the locality resistance of wind and water.Models presented in this part are the basics of design of controller of air conditioning system.Then,overall design of air-conditioning system is presented based on engineering project,in which the design of cold and heat source,air conditioning unit,fresh air ventilator,tail end fan coil is concluded.And the equipment selection is presented based on the requirement of the system performance index.The drawback of PID controller is analyzed according to the non-linearity,large lag and large inertial of the air-conditioning system.Fuzzy-adaptive PID controller is presented to solve the problems above,in which the parameters of PID is adjusted by the fuzzy control rule,and by which favorable dynamic quality and steady state is gained.Finally,a simulation model is constructed base on MATLAB Simulink,via which a simulation experiment is completed in order to verify the efficiency of the presented controller.A comparison is presented between the traditional PID controller and Fuzzy Self-adaptive controller performance.Results of simulation show that the presented method improves the dynamic and steady state of air-conditioning system,and also the over-shoot and accommodation time is reduced,the control precision of temperature are roved.The system show nice operation effect via field debugging and it achieves the requirement of designing.The simulation and projects show that the Fuzzy adaptive PID controller improves the energy conservation and efficiency characteristic of the air-conditioning system.