| Climate changes affect the energy consumption,the development and utilization of energy impacts climate changes.Recent years,climate change complex severe.And it has certain influence on the energy consumption of air conditioning.VAV BOX as the key part of variable air volume air-conditioning system,the operation has a direct impact on the running effect of the whole air conditioning system.Researching control strategy on the VAV BOX of variable air volume air-conditioning system based on climate compensation has important practical significance.The concept of climate compensation in heating system is introduced into the variable air volume air-conditioning system.The heat load value is expressed as a function of supply air temperature by heat exchange analysis.The scheme of climate compensation and the method of optimizing supply air temperature are proposed through analyzing the heat exchange and the control part in the air-conditioning system.And the thesis is based on the proposed climate compensation experiment scheme,through the engineering experiment method to determine the optimal supply air temperature value under the minimum fresh air volume and different indoor temperature setting value in winter and summer conditions.It makes the relationship between the outdoor temperature and supply air temperature clearly under the certain condition.The thesis is based on variable air volume air-conditioning experiment system in Xi’an University of Architecture and Technology,and in order to study the model by system identification method.The open loop identification method is used to modeling for the fan,two pumps and air temperature control circuit.And the MATLAB software is used to design the controller and simulate based on the object characteristics.Thecontrol algorithm is applied to the actual operation system,and it has a good control effect.These model and control algorithm are used to ensure the operation system stable for climate compensation experiment.The experimental result proved the feasibility of climate compensation scheme.It has a certain energy saving and supplys a new solution for engineering application.Finally,taking the non-open characteristic into accout to design the VAV BOX control platform based on PLC.And closed-loop identification modeling method is used to the air damper and room.The inner loop adopts PI control,the outer loop uses the improved single neuron self-adaptive PID control.Using MATLAB software to simulate.The results show that control effect is good. |
