The Design Of Air Conditioning Control System Based On Human Comfort

Today,people spend most of their time in buildings.The indoor environment not only affects people's work efficiency,but also affects people's health,Requirements on indoor environmental quality and comfortability are becoming more and more demanding.The traditional air conditioning takes the temperature as the control parameter,and ignores the influence of the indoor environment factors,such as relative humidity,indoor wind speed and average radiant temperature on the human body comfort.The control purpose is to maintain temperature rather than human comfortability around the set value,so to a large extent it cannot meet people's increasing requirements on comfortability.It is hoped that the change of indoor environment is based on the sense of comfort.Therefore,it is of great theoretical and practical significance to study the environmental regulation of air conditioned room.In this thesis,the PMV index,which is widely recognized as a comfortability index,is used,and a control system of air-conditioned room based on human comfortability is designed.Firstly,this thesis analyzes the human comfortability index of PMV,which contains four environmental factors(temperature,relative humidity,wind speed and the average radiation temperature)and two non-environmental factors(metabolic rate,clothing insulation).Then we use MATLAB simulations to determine the environmental factors in the controllable factors(temperature,relative humidity,wind speed)on the degree of influence of PMV,in roder to provide theoretical support for the control strategy.Based on the characteristics of indoor environment,we design a wireless sensor networks,the main control module of STM32 and the Android mobile device client.We use the wireless sensor networks to collect indoor environmental parameters,which do not change the pattern of the room,and avoid wiring trouble,what's more,the wireless sensor networks can also not affect the original indoor environment.The main control module of STM32 is mainly responsible for the data processing and controlling-command transmission,the module is low economic costting,stable performanceand low power consumption for a long time;Android mobile device client is the main interface of human-computer interaction,providing users with a user-friendly experience.Through the analysis and research of PMV control mode,it is difficult to realize the direct control mode of PMV in practical engineering,this thesis chooses PMV indirect control mode,the PMV indirect control means the comfort index PMV as the reference standard of the control system and not the direct control parameter.Based on the theoretical study of human comfort,this thesis establishes the optimization model of temperature and humidity in thermal comfort room.The model is solved by using the method of nonlinear constrained minimization of the calculated set comfort of the most suitable parameters,and through the corresponding settings to set the comfort index.Then the interval PMV control strategy is proposed based on the research of comfort interval and the parameter optimization model,and it maintains the comfortability index within a desirable range.Lastly,the mobile client interface is demonstrated,and the experimental results show that comfort control can provide better comfort experience.