The Research Of Daylighting Control Strategy And Energy Saving Analysis

People have paid more and more attention to the energy situation and environmental problems since the energy crisis broke out in the seventieth of last century. In the past few years, our country has gained great progress in the social and economic fields. At the same time we are facing more and more serious situations of energy supply shortage and environmental pollution. Through conserving energy and improving energy efficiency, we can alleviate the situation effectively. Building energy use accounts for a great quotient of the total energy consumption. For commercial and office buildings, their energy use mainly includes two parts, one is consumed by HVAC system, and the other is used by lighting system. Our country is rich in daylight resource. Making sound use of daylight and reducing lighting energy consumption can save building energy use, which is also a useful method for improving building energy efficiency.Different from artificial light, daylight is very changeful according to time, weather, and seasons. Daylight includes two parts, direct sunshine and scattered sunshine, which is caused by the particles floating in the sky. When the daylight penetrates through the window into a room, its distribution is very complicated. This brings difficulties for the daylight harvesting control. The thesis analyses several main factor influencing daylight harvesting. We build an initial model for daylight harvesting. We implement daylight harvesting through the control of window blind. Nowadays, the window blind is always manually controlled, because the automatic control system is elusory and the frequent motion of the window blind may affect the mood of people inside the room. For solving these problems, we use the fuzzy inference strategy, which mainly employs people's experiences. This system can make use of daylight effectively and alleviate the frequency of motion of the window blinds. For artificial lighting, the usual situation is that, the first person entering the room opens the lighting system in the morning, and the last person leaving the room closes the lighting. This inevitably brings lighting energy waste. The paper introduces several automatic lighting control systems, which employs ON/OFF switch control or daylight dimming control. We propose an integrated control strategy for dayligting and lighting control. If there are people in the room, we employ the luminance priority strategy; if not, we employ the energy priority strategy. The goal of making use of daylight is saving energy. We calculate the energy use under different control strategies, including not implementing control, ON/OFF switch control, and dimming control. Through comparison, we can make such conclusions: both ON/OFF switch control and dimming control can bring about great energy savings; compared with ON/OFF switch control, dimming control can save more energy.