Research On Control Strategy Of VAV Air Conditioning System Based On Intelligent Algorithm

At this stage,China is on the road of industrialization and urbanization,and its energy demand continues to grow.It has become the world's second largest energy consumer after the United States.The energy contradictions have become increasingly prominent,and the everincreasing energy consumption and energy consumption of buildings have increased.The issue of resources and the environment has become a key issue in the field of architecture.In the past 30 years since building energy conservation and energy conservation were proposed,remarkable achievements have been made and a sound energy efficiency standard for buildings has been established,which has made society pay more and more attention to building energy conservation.As an important part of a building,the HVAC system generally consumes more than half of its energy.Therefore,HVAC control is the key to building energy efficiency.VAV air-conditioning systems are used in many large-scale public,civil,and industrial buildings due to their advantages of energy saving,flexible control,and comfort.They gradually replace fixed-volume air-conditioning systems,and their market share is gradually increasing.There are more and more researches on optimization control technology of HVAC.In this paper,variable static pressure control method called "Trim and Response Method(TR)",was used in an office building in Beijing to optimize the original air-conditioning system air volume control method.The TR logic measures the requests from all VAV terminal units and resets the static pressure setpoint accordingly.In sequence,the supply and return fan in the air handling unit(AHU)adjust the speed automatically to maintain the static pressure at its setpoint.As a result,at least one VAV damper is nearly fully open and the pressure resistance is thus minimized.Based on the successful operation of the variable static pressure control method,a system-wide energy consumption model including the energy consumption of cold/hot water,fan energy consumption,and end reheat energy consumption was established.The particle swarm optimization algorithm program written in MATLAB is used for the air handling unit.The air supply temperature is optimized so that the energy consumption of the entire system is the lowest.The control program was written by Niagara,an Internet of things middleware platform,and built into Building Automation Systen(BAS).The actual control data compares the energy saving effect of the optimized control.The results show that,while ensuring comfort,the energy saving effect of variable static pressure control is better than that of total air volume control,and the energy saving of the fan reaches 12.6%.The goal of optimizing the air supply temperature based on the particle swarm optimization algorithm is achieved,and the energy saving rate is 13.7%.