The Study And Design Of Variable Flow Energy-saving Control Systemfor The Central Air Conditioning

Energy is the material basis of human survival and social development, Energy conservation is a major strategic issues that protection of economic and social sustainable, rapid and healthy development. With the development of China’s urbanization and industrialization process, the size and number of public buildings and industrial buildings are Increasing. Building energy consumption is rising, Building energy efficiency occupies an important position in the field of energy saving applications. As the indispensable infrastructure of modern architecture, central air conditioning create a comfortable and efficient working and living environment for people, it also brings a great deal of energy consumption, the energy consumption of central air-conditioner system accounts for about40%～60%percentage of the energy consumption of building trades, the central air conditioning system of saving energy and reducing consumption increasingly cause the attention of people. Traditional central air conditioning water system runs based on a constant flow, the building equipment selection according to the maximum cold and heat load, and leave a sufficient margin.But the air conditioning system load changes with the changes of the outdoor weather conditions, most of the time,the delivery of water are in excess,causing serious waste of electricity. Therefore, the constant flow operation mode be replace to variable flow operation has become the inevitable trend of central air conditioning system to save energy.This paper outlines the history of the development of the central air-conditioning water system, studied the working principle and implementation methods of energy-saving control system for the central air conditioning, designes a central air-conditioner control equipment for saving energy. The device as the core of energy-saving controller combined with a frequency converter, Variable flow operation control of the central air conditioning by collecting temperature and pressure of cold water system. System load conditions through the set up different control parameters to reasonable reflection, make air conditioning system to better suit load changes.There are great non-linearity, lag and variety of parameter in this system.Traditional PID control arithmetic has some difficulty.But there is error in fussy-control by limited grade. This design combines the advantages of fuzzy control and PID algorithm, puts forward a parameter adaptive fuzzy PID algorithm. This will not only be able to quickly adjust the temperature, and improve system stability, but also to the steady state error is smaller.The anti-interference ability of this control system is strong.It can satisfy completely the need of variable-flux equip,has vast of market foreground.