Shading is an effective way to save energy in buildings. Through good shading design, it can not only save energy, but also enrich the indoor light distribution, but also enrich the building shape and facade effect. Let's take a look at the use of intelligent sunshade system in intelligent buildings.
Nowadays, the indoor and outdoor environment of the building is controlled in an intelligent or automatic way, in order to achieve the safety and energy saving of the building. when the intelligence of HVAC and lighting system is gradually accepted by people, many advantages of intelligent sunshade system are ignored.
Different from the old sunshade system, the intelligent sunshade system is usually composed of sunshade blinds (curtains), motor and control system. The software of the control system is a part of the intelligent sunshade control system, which is used in conjunction with the hardware of the control system. According to the changes of the surrounding natural conditions, the angle of the curtain can be automatically adjusted or raised or lowered through the system circuit to complete the intelligent control function of the sunshade blinds, which can not only block the radiant heat, reduce direct sunlight, avoid glare, but also make full use of natural light and save energy.
According to its own characteristics, intelligent sunshade system can be divided into artificial electric control and induction intelligent control. Artificial electric control can artificially adjust the angle of the sunshade system according to the angle and intensity of sunlight in a day. On the other hand, the induction intelligent control automatically adjusts the shading direction, angle, position and shading area of the sunshade board through the induction of the position, direction and intensity of the sun exposure height of the probe, so as to achieve the purpose of sunshade. This kind of sunshade system has a very good effect on the sunshade used in roof lighting system.
Intelligent sunshade system mainly depends on its intelligent control system to achieve the purpose of energy saving.
At present, the most widely used intelligent sunshade control system is based on LONWORKS control network technology, which can achieve the following functions: according to the local meteorological data and sunshine analysis results, the system calculates the solar elevation and azimuth in different seasons, dates, different periods and different orientations. Then the intelligent controller controls the flip angle of the louver in different directions according to the set period of time. A multi-directional sun sensor set on the roof is used to detect whether it is sunny or cloudy. On a cloudy day, the system controls the louver to open horizontally; on a sunny day, it is executed according to the automatic sunlight tracking mode. at the same time, an occlusion model is established according to the shape of the building and the surrounding buildings, and the daily shadow change of the reference point is calculated. it is stored in the motor controller and runs automatically according to the results.
The software of intelligent sunshade control system includes two parts: computer monitoring software and intelligent node control software.
3.1 principle of automatic sunlight tracking and blade flipping.
According to the longitude and latitude of the building, the software can be used to calculate the sun elevation and azimuth in different seasons and different times, and the results can be stored directly in the motor controller. The motor controller will automatically calculate the corresponding sunlight angle and automatically flip the blade to the appropriate angle to block the direct sunlight with the set angle as the step.
3.2 set up sun tracking.
According to the shape and orientation of the building, several reference points are set on the facade of the building, and the four seasons sunshine analysis is carried out on the reference points.
According to the orientation and height of the building, the sun elevation and azimuth of each reference point in different seasons and different times are calculated by LONWORKS software.
The calculation results are stored in the motor controller of LONWORKS and run automatically.
Flip the angle of the leaf at any time, while preventing the sunlight from coming directly into the room, expand the angle as much as possible, maintain a good visual effect, and let the natural light reflect to the indoor ceiling.
3.3 calculate the shade of the building against the sunshade.
In the process of the operation of the sun, the building itself casts a shadow on the neighboring buildings, and the surrounding tall buildings may also have a blocking effect on this building. The window cast by the shadow does not actually need shading, otherwise the room will darken, so the leaves need to be horizontal or folded away.
Build the model according to the building plan and elevation.
Using the elevation and azimuth of each reference point just calculated, the shadow change of each day and year is calculated according to the shadow of the building around the building and its own shape and orientation.
Once these data are calculated, they are recorded in the LonWorks louver controller.
At different times, the louver controller automatically knows which reference points are located in the shadow according to the stored calculation results, and flips the blade to the horizontal position to let more light into the room.
Intelligent sunshade system is an indispensable part of building intelligent system. As a sunshade system that can improve building indoor environment and improve building living quality, intelligent sunshade system will be the most potential branch of building intelligent system and will also make a great contribution to energy conservation. And with the continuous progress of technology and the popularization of building intelligence, building sunshade will have a more complete intelligent control system, and the use of intelligent sunshade system in intelligent buildings will be more and more prominent.