Research On Temperature And Humidity Decoupling Control Method Of VAV Air Conditioning

With the continuous progress of building equipment and technology,air conditioning systems have become an indispensable part of modem buildings,and also one of the important sources of social energy consumption.In this paper,the coupling problem of temperature and humidity regulation in VAV air conditioning system is discussed.An adaptive PID controller based on inverse system is designed to improve the control effect of temperature and humidity on the prem ise of decoupling temperature and humidity.In this paper,by studying and analyzing the working principle of the variable air volume air-conditioning system,the human comfort range and the dynamic change process of humid air,a double closed-loop control loop of room temperature and humidity is established respectively,and the coupling characteristics of the air-conditioning system in the process of adjusting the room temperature and humidity are analyzed.Using mechanism method and parameter identfication,the transfer functions of the inner loop and outer loop of temperature and humidity and the coupling transfer function in the adjustment process are obtained respectively.Aiming at the disadvantages of traditional feedforward compensation decoupling control methods such as long adjustment time and large dynamic deviation,a decoupling scheme based on the RBF neural network inverse system is proposed By constructing a pseudo-linear system composed of the inverse system and the original system,the original coupling is made The circuit becomes a single-input single-output system,so as to realize the decoupling of temperature and humidity.Combine the decoupler with the BP-PID controller to form a closed-loop control,so that the temperature and humidity of the air-conditioned room can be output stably within the specified range to achieve the control effect required by the system.In order to solve the problems of BP neural network local extreme value and poor generalization ability,compare the optimization effect of PSO and GSO on the weight and threshold of BP neural network,adopt GSO algorithm to self-tuning BP-PID controller,and further improve the temperature and temperature of air-conditioning room.Relative humidity control accuracy.The decoupling controller designed in this paper is applied to the temperature and humidity control loop,and the simulation analysis is carried out to verify the decoupling control effect.The experimental results show that:Compared with the traditional feedforward compensation decoupling control,the GSO-BP-PID controller based on the RBF inverse system makes the temperature and humidity control system output more accurate,the overshoot is smaller,and at the same time stability and anti-interference ability It has also been improved and a good control effect has been achieved.The research on the temperature and humidity decoupling control of variable air volume air-conditioning in this paper provides a certain reference value on the technical and theoretical level for solving the multi-loop decoupling control and energy consumption research of variable air volume air-conditioning.