1 Overview
In recent years, with the rapid development of China's automobile industry, the lighting level of factories has increased year by year, and the consumption of lighting energy has also increased year by year. However, the contradiction between power supply and demand has become more and more prominent. The lack of energy has seriously restricted the development of various industries including the automobile industry. The issue of energy conservation has become a long-term strategic policy of China. Lighting energy-saving design has become every electrical designer. Issues that must be carefully considered.
In the automobile factory, there are mainly three types of lighting design projects: factory lighting design engineering, integrated office lighting design engineering, and factory road lighting design engineering. The following are discussed separately.
2 Plant lighting engineering energy-saving design
2.1 Selection of high-efficiency energy-saving light source
Automobile factory buildings generally belong to tall industrial plants. When there is no special requirement, high-intensity gas discharge lamps (HID) represented by metal halide lamps should be preferred. Because metal halide lamps have the characteristics of high light efficiency, good color rendering, high power and long life, they are suitable for large-area lighting.
The height of a single-storey factory in a car factory is generally 8 to 15 m, and 250 W and 400 W are often used.
2.2 Selection of high-efficiency energy-saving lighting fixtures
According to the recommendations of the International Commission on Illumination (CIE), lamps are classified into five categories according to the distribution of luminous flux in the upper and lower spaces: direct type, semi-direct type, full diffused type, semi-indirect type and indirect type. Since the automobile factory building is generally tall and the maintenance is not convenient, it is necessary to select a direct type lamp with high utilization coefficient, reasonable light distribution, high reflection efficiency and good durability. Plate-type luminaires are preferred. The function of the plates is to make the reflected light change the path, leave the bulb, increase the light output, improve the efficiency of the luminaire, and extend the life of the lamp. Generally, the efficiency of the panel lamps is about 5% to 20% higher than that of the smooth surface lamps. The light distribution of the lamps should be reasonably selected. According to the relatively high characteristics of the factory buildings, lamps with narrow light distribution can be selected to improve the utilization factor.
The lamp should be equipped with a glass cover, and the efficiency of the lamp should not be lower than 55%. The structure of the luminaire should be such that it is easy to install, maintain and replace the light source.
2.3 Selection of high-efficiency energy-saving electrical accessories
2.3.1 Using energy-efficient magnetic ballasts and electronic ballasts
Factory lighting should use low-energy, high-performance light source electrical accessories, such as electronic ballasts, energy-saving magnetic ballasts, electronic triggers, etc., gas discharge lamps should use electronic triggers. Generally, the inductive ballast itself consumes 10% to 15% of the light source, while the electronic ballast itself has extremely low energy consumption and has the characteristics of constant power output. At present, about 90% of the gas discharge lamps in the factory are equipped with magnetic ballasts. If energy-saving magnetic ballasts, electronic ballasts and electronic triggers are used to replace the traditional high-energy magnetic ballasts, great energy savings will be obtained. benefit.
2.3.2 Implement single lamp capacitor compensation
The single lamp compensation of the factory lamps is to compensate one capacitor in parallel with each set of lamps, and the power factor is increased to 0.85 or more, which can reduce the reactive power of the circuit, reduce the line loss and voltage loss, and at the same time, because the line current is reduced. Use a smaller cross-section of the wire.
2.4 Energy-saving design of lamp layout and loop control
There are many tall equipments in the paint shop and stamping workshop of the automobile factory. When arranging the lamps, the influence of the tall equipment on the lighting should be considered. The layout of the lamps should avoid the tall equipment. The assembly line of the assembly shop generally requires a higher illumination. These three workshops should adopt a hybrid illumination system that combines the general lighting of the plant with the channel, equipment or local illumination of the production line. Metal halide lamps are used for the roof, and energy-saving fluorescent lamps are used for the local lighting of the passages, equipment or production lines.
The lighting partition control shall be carried out in the workshop according to the workshop, the working section or the production line process. The lighting switch shall be appropriately added. The lighting fixtures of each lighting switch shall not be too much. The control box shall be arranged on the passage convenient for the staff to operate. The guard lighting circuit is controlled separately.
2.5 Other lighting power saving measures
2.5.1 Selecting reasonable illumination and power density values
The newly revised "Architectural Design Lighting Standards" (GB 50034-2004) specifies the standard values ​​for general illumination illuminance. Local illumination should be selected from 1 to 3 times the general illumination illuminance value of the site. The new standard specifies the maximum allowable value of the building's lighting power density and should be strictly observed.
2.5.2 Reducing losses on the power supply line
Lighting circuit distribution should ensure that the three-phase power is basically balanced to reduce line loss.
2.5.3 Building design and lighting energy saving
When designing the plant, the electrical designer should consult with the building professionals to save the lighting power by changing the area of ​​the window (including the skylight and wall window) and using the natural light reasonably and fully.
3 Integrated office lighting design project
3.1 Selection of high-efficiency energy-saving light source
Generally, high-efficiency energy-saving fluorescent lamps (such as T5 and T8 tubes) and compact fluorescent lamps should be used in office rooms of automobile factories. The use of incandescent lamps should be minimized. The design advocates the use of T8 rare earth trichromatic fluorescent tubes instead of T12. This is because T8 lamps have higher color rendering index and light efficiency than T12 lamps, with low light decay, long life, and low mercury consumption, which is more in line with energy saving and environmental protection requirements. In addition, since the lamp power is higher, the light efficiency is higher, and a 36 W light source should generally be preferred.
Halls, corridors and other places are mainly compact fluorescent lamps (including "H" type, "U" type, "D" type, ring, etc.), replacing incandescent lamps.
Incandescent lamps can be used in the case of frequent opening and closing, small area, and low lighting requirements. Since the double-spiral filament type incandescent lamp is 10% higher than the single-spiral filament type incandescent lamp, it should be preferred.
3.2 Selection of energy efficient lighting fixtures
Direct lighting is preferred in general office areas, and high-efficiency gratings are preferred in office spaces with ceilings.
Reasonably choose the light distribution of the lamps. When the room space is smaller than the RCR value (the room is short and wide), it is advisable to use a wide-lighting luminaire; conversely, when the indoor space is larger than the RCR value (the room is narrow and high), a narrow-lighting luminaire should be used to Increase the utilization factor. 3.3 Selection of high-efficiency energy-saving electrical accessories
For integrated energy-saving lamps and single-ended low-power fluorescent lamps (that is, power less than or equal to 25W), electronic ballasts should be preferred because their harmonic requirements, abnormal protection functions, and preheating requirements are relatively low. For a straight tube fluorescent lamp of 25 to 65 W, an energy-saving magnetic ballast is preferred. This is because energy-efficient magnetic ballasts are more cost-effective than electronic ballasts. In addition, electronic ballasts have obvious advantages in terms of their own power consumption and light efficiency ratio, and Others are not as good as energy-saving magnetic ballasts. For example, when the current is on, the surge current is large, the external electromagnetic interference is serious, the harmonic content of the power supply current is high, the transient overvoltage capability in the power supply is low, and the service life is short.
3.4 Energy-saving design of lighting arrangement and loop control (1) The lighting switch is separately set on the side of the window to control the lighting range of the lighting according to the change of natural light. (2) Appropriately increase the number of lighting switches in each room to achieve zone control. (3) Lighting in public places such as foyer, stairs, toilets, corridors, etc. should be controlled centrally, and appropriate power-saving switches (such as voice control, time control, light control switches, etc.) should be used. (4) The office used by the individual automatically switches the light by means of human body induction or motion and static induction.
3.5 Other lighting power saving measures
3.5.1 Room decoration affects lighting energy saving
The effect of the ceiling and wall facing the lighting effect is related to the room area. The ceiling of the small room has a small proportion of the field of view, the influence of the contrast is small, and the proportion of the wall in the field of view is large, and the influence of the contrast is large. Therefore, the small room can use the wall with high reflectance and the ceiling with low reflectance. Conversely, large rooms use high reflectance ceilings and low reflectance walls.
3.5.2 Make full use of natural light to discuss the same plant lighting project
4 Factory road lighting design project
4.1 Selection of high-efficiency energy-saving light source
At present, the main types of light sources used in street lighting of automobile factories are: metal halide lamps, high pressure sodium lamps, fluorescent high pressure mercury lamps, and the like. Among them, the high-pressure sodium lamp has the advantages of long service life (24000h), high luminous efficiency, strong fog permeability, energy saving, moderate color temperature, and is suitable for road lighting with low color rendering requirements, and is widely used. In recent years, metal halide lamps have been widely used in street lighting systems. It is one of the most ideal energy-saving light sources with high luminous efficiency, high brightness, high color rendering, multi-tone and long life.
4.2 Selection of energy efficient lighting fixtures
Street lighting fixtures should have a higher utilization factor, reasonably choose the light distribution of the lamps, prefer to use block-type lamps, try to choose lamps without accessories, and choose lamps with high retention. The degree of protection of the luminaire is at least IP44.
4.3 Design of lighting method
There are generally four basic types of lighting: single side lighting, central lighting (including central single lighting, central symmetrical lighting), staggered lighting and symmetrical lighting.
The symmetrical arrangement is more beautiful, but the disadvantage is that the illumination is not uniform enough for a wide road. Although the staggered arrangement is not as beautiful as the symmetrical cloth, the illumination is relatively uniform.
Automobile factory road lights can generally be 8 to 10 poles high, and the distance between lamps is 30 to 40 meters. The main road adopts symmetric arrangement on both sides, the secondary trunk road adopts single-side cloth light, the test runway is staggered, and the parking lot adopts 35m flying butterfly-shaped high pole light. The position of the street light is suitable for normal traffic.
4.4 Energy-saving design of street lamp control mode
Because the factory area of ​​the automobile factory is generally large, it is impossible to control the street lamps of the entire plant with a street lighting control box. Therefore, the factory is divided into several areas, and several street lighting control boxes are set up to control the street lights in this area. There is a set of intelligent lighting control devices in each lighting control box. There are two main control methods in power supply and energy saving: using midnight light and adopting voltage regulation. The midnight light control method refers to the method of turning off a part of the street lamp in the middle of the night to achieve energy saving, and has the characteristics of being simple and easy to operate; the disadvantage is that the road lighting is uneven. In addition, because the voltage variation of the factory day and night is often 5% to 12%, the line voltage is generally 3% to 5% after midnight. At this time, the power of the running lamp often exceeds 10% of the rated value, and the high voltage not only wastes power. It also shortens the life of the bulb.
The voltage regulation control method refers to the method of reducing the power supply voltage to achieve energy saving and prolonging the service life of the light source, which is a better energy-saving control method. 4.5 Other lighting energy-saving measures Gas discharge light source should implement single-lamp local capacitor compensation, increase the power factor to above 0.85, and reduce reactive power loss.
In the design of the distribution line, appropriately increasing the cable cross section can not only reduce the voltage drop caused by the long line, but also reduce the line loss and system stability due to the small voltage drop, which prolongs the life of the whole system. It also saves energy. Through the discussion on the energy-saving design of the three main lighting projects of the above automobile factories, it can be found that the energy-saving design potential of building electrical is great. As an engineering designer, we should work hard to learn new technologies and new methods, rely on our own advanced scientific and technological knowledge, carefully consider in the design work, repeatedly compare and design the optimal plan to meet the functional requirements, and save for the construction of China. A society that contributes to sustainable development and contributes to it.
Longdi Light Equipment Technology Co., Ltd , http://www.gz-ledlight.com