Energy-saving Control Of The Subway Station Central Air Conditioning System

Today the growing scarcity of energy, energy conservation has become a hot topic insociety, all walks of life are starting to advocate saving energy. Subway station central airconditioning system is the largest part of the energy consumption of the station, central airconditioning system energy saving is an important part of building energy efficiency at thestation.This article introduces the significance and research status of central air conditioningsystem energy saving, theoretically elaborates the basic principle of central air conditioningsystem variable flow energy-saving. The article also introduces the subway station centralair conditioning system from the HVAC system and the water cooling system, describesseveral energy saving operation scheme in detail. The central air conditioning system ismore than one parameter, nonlinear, time-varying system. This paper uses chilled watersystem as the research object of variable flow energy-saving control, uses a second ordermodel with pure lag link to approximate the controlled object. The conventional PIDcontroller and the fuzzy PID controller was designed in view of the controlled object.Separately simulation research to chilled water flow variable flow energy-saving controlsystem composed of two controllers. Compared simulation control effect of conventionalPID and fuzzy PID controller in the chilled water flow variable flow energy-saving controlsystem, from the unit step response curve it can be concluded that the fuzzy PID controllerhave short response time, small overshoot and a good robustness. Under the condition ofthe controlled system parameters changed little the fuzzy PID controller can get betterenergy saving effect. Finally using Siemens S7-300PLC as the platform, the fuzzy PIDcontrol algorithm is discussed in detail.