Research On Variable Static Pressure Control Of Variable Air Volume Air Conditioning System

People faced the problems of the climate and environment are getting more and more serious.For the construction industry,it with a large of energy consumption and now the issue of green building has been put on the agenda,so it is necessary to study the building energy saving deeply.The energy consumption of central air conditioning system occupies a large proportion in the total energy consumption of building electr ical equipment.However,with the continuous deepening stud y on the variable air volume air conditioning system and by the virtue of its own advantages,variable air volume air conditioning system is more and more used in large complex buildings.Variable static pressure control in wind system of variable air volume air conditioning system can be based on the actual load demand of the system air conditioning area and adjust fan speed in real time,in the premise of meeting the load demand to make the wind turbine running at the minimum speed and then realize energy saving.Compared with the existing control method,variable static pressure control has better control and energy saving effect to the variable air volume air conditioning system.But under the control of the existing control mode or related algorithm,the system has the proplem of the tracking performance is not ideal,poor stability,dynamic performance needs to be improved and unstable transition state.In order to improve the tracking performance,improve dynamic characteristics and can further achieve energy saving of the system,this topic is based on the experimental platform of the Intelligent Building and Building Automation Laboratory of Xi’an University O f Architecture And Technology.First,using the system identification met hod to set up the mathematical model of the fan frequency-static pressure circuit in the wind system and in the end obtain the system transfer function with first order delay.Secondly,a new desired trajectory of static pressure set value is given and used to sudy of the simulation.Furthermore,based on the variable static pressure control,combination of PD type,fast integral PID type and fuzzy gain PD type iterative learning control algorithm to do the simulation.Finally,the above control algorithm is programmed by Lab VIEW software and applied to the experimental platform and do the research on the experimental control of the research object.Through the data analysis and comparison of the simulation and experimental,it can get result that under the control of the fuzzy gain PD type iterative learning algorithm,system can better track the desired static pressure set value,it is dynamic performance can be improved and the energy consumption of the fan in the system is relatively small.