Research On Optimization Control Of Indoor Comfort And Energy-saving Environment Of Buildings

Higher and higher requirements are placed on indoor comfort and air quality as people spend more time indoors.The central air-conditioning system is an important means to realize the above requirements.Nevertheless,due to its large equipment group and complex system operation,it consumes a large amount of energy while creating a comfortable and healthy environment,and its energy consumption accounts for more than 50% of the building energy consumption.Therefore,it is of great significance to study the minimum energy on the premise of comfort and air quality.In the traditional researches that simultaneously meet the goals of indoor comfort and energy-saving in buildings,the model is built on the energy balance of a single variable or a single device,an accurate mathematical model is lacking as the basis for optimization;The energy saving optimization method is single and the effect is not idea;The Pareto method is mostly uses in the research of comfort-energy,which has certain defects;Therefore,aiming at the existing problems in the indoor comfort and energy-saving environment of buildings,a mathematical model is established,the energy-saving optimization method,comfort-energy optimization strategy and the control method of indoor comfort and energy-saving environment are studied.Firstly,a dynamic model of indoor space is established which is regulated by air handling units.The relationship of mass and energy balance are analyzes of indoor space and air handling units.Effectiveness and feasibility is verified by an example.On the basis of the constraint of the model,the energy-saving optimization method called comfort-zone is proposed with the constrain of the range of critical degrees of freedom and the normal operation condition of air handling unit,minimizing the total energyconsumption as the goal.To prove the universality of the comfort-zone optimization method,simulation experiments were conducted on the energy consumption in winter and summer working conditions respectively,and the results were compared with the traditional set-point tracking method.The simulation results show that the proposed method can reduce the energy consumption while satisfying the comfort,and about 70%energy consumption can be saved compared with the traditional method.Secondly,based on the established model,the comfort-energy optimization is studied,and a compromise tracking strategy is proposed.The strategy obtains the weight by solving the coordinates of the point closest to the limit performance in the feasible region.The simulation results show that the compromise tracking optimization strategy can solve the conflict between comfort and energy-saving without calculating the pareto front,with good performance and the steep pareto peak can be handled efficiently.The strategy is suitable for real-time management of building energy and multi-objective optimization of multiple combinations.Finally,the indoor comfort and energy-saving control method of buildings is studied,and thermal comfort fuzzy control method is proposed.Based on the established dynamic model,thermal comfort control strategy and fuzzy control algorithm are adopted to control the result of the proposed comfort-zone optimization method.The results show that the air-conditioning system with thermal comfort fuzzy control method has smaller adjustment time and overshoot,and can keep the comfort level within the range of ±0.2.The structure of the controller is simple without too much reconstruction cost,and is easy to realize.