Have a short life because incandescent, energy consumption, coupled with the rising cost of energy for many reasons, incandescent launch stage of history is an inevitable thing, then replace it with the energy-saving lamps and LED lights, that could do better? Before that the true successors of incandescent? we might look, energy-saving lamps and LED tube set.
One: the status of energy-saving lamps
In recent years, our country has been through a lot of manpower, material and financial resources to promote the use of energy-saving lamps. With the phase-out of incandescent lamps is ‘Proton’ out of the market for energy-saving lamps brings a huge space for development, more and more companies have introduced energy-saving lamps lighting products, to seize the remaining market.
energy-saving lamps
Currently, energy-saving lamps are the most widely used everyday consumers incandescent replacement product. Its efficiency is more than five times of incandescent bulbs, the average life of about 8000 hours, mature technology, and lighting, lamps matching, and is a simple and relatively low-cost replacement option. However, energy saving and environmental protection should complement each other in this, but in the energy-saving lamp body, but both went to the opposite, the problem is bound mercury will eventually be replaced with energy-saving lamps fate: a common energy-saving lamps average mercury content 0.5 mg, The mercury dipped underground about 180 tons of water may cause pollution. If the improper disposal of waste energy-saving lamps, is likely to become “eco-killer”, and waste energy-saving lamps have also been mishandled ‘good years’, and even today is still no appropriate policies and measures introduced. Two:LED tube set
Longer life LED light source, high efficiency, energy saving, environmental protection and other “theoretical advantage” has passed the test of practice, LED light source of the performance parameters have not always used to say, “improving”, but “further improvement” LED industry’s overall development prospects are generally good.
LED tube set
With the phasing out of incandescent and state subsidies for energy-saving lighting products, LED lighting market has been accelerating. Even in 2012 the industry hopes to popularize the first year of LED interior lighting, LED is gradually tentacles deep into the home lighting market. But now LED lighting products, price issue is still hindered LED home lighting market inroads into the most important factor. In terms of price, the market is 1.2 m long, 21 watt LED lamp normal retail price of 200 yuan, while the same length and wattage of traditional fluorescent tubes basic price less than $ 10; incandescent replacement cost, LED bulbs with the traditional energy-saving lamps in normal circumstances, there are at least eight times higher than the price difference. This price gap is naturally LED lighting into the home environment, the biggest obstacle. Many dealers also said lamps, LED home lighting is still in the promotion phase, more consumers still tend to buy relatively low price energy-saving lamps; in the home market, energy-saving lamps LED lighting products remains the biggest rival, And it is always home lighting energy-saving lamps areas of expertise.
LED tube set fixture is undoubtedly the future direction of development, but how to reduce the cost of LED lamps LED whether the popularity of the market has become an important part. In fact, at this time there a few years, LED lighting prices are at an annual rate of 35% -50% down, I believe that in the near time, LED lamps prices will drop to every household acceptable range, that time is LED lighting era has arrived.
LED is a low-voltage semiconductor and punctuate cold led light with longer life, high efficiency, energy saving, environmental protection and other “theoretical advantage”, which has passed the test of practice. The performance parameters of LED light source are not used to say “improving” or “further improvement “, The overall development prospects in LED industry’s were generally optimistic.
With the phasing out of incandescent lamps and the energy-saving lighting products, and services, led lighting market has been accelerating. LED is gradually entering into the home lighting market, but the price issue of LED lighting industry product is still hindered in LED home lighting market, which is the most important factor. In terms of price, the market retail price for 1.2 m long, 21 watt led lamp is 200 yuan, while the same length and wattage of traditional fluorescent tubes’ price is less than $ 10; In normal circumstances, the price difference between incandescent replacement cost and LED bulbs with the traditional energy-saving lamps are at least eight times higher. This price gap is naturally the biggest obstacle for LED lighting into the home environment. Many dealers also said lamps, LED home lighting is still in the promotion phase, more consumers still tend to buy relatively low price energy-saving lamps; in the home market, energy-saving lamps is the biggest rival for LED lighting products, And it is always a new areas of expertise for home lighting energy-saving lamps.
Mainstream LED lights for lighting trends
LED lighting fixture is undoubtedly the future direction of development. It is worth pondering, and with policy support. LED industry maintains the doubled growth rate for many years, but they did not start the LED lighting civilian market. In addition to higher prices, instability quality, not high cost is the main reason. In fact, at this time of few years, LED lighting prices are at an annual rate of 35% -50% down, I believe that in the near future, LED lighting prices will drop to a reasonable range that every household can be acceptable, at that time, it is the LED lighting era. LED lights for energy-saving lamps prevailing trend
In the wave of restructuring traditional lighting to LED lighting, some manufacturers in the market competition are inevitably eliminated, but some steady development based on technological, after emerging industries must withstand any test of the market to mature, this is the process for any kind of conventional light sources, traditional lighting and LED lighting are representative of different stages of development. LED industry’s rapid development, the government’s promotion efforts, All this does not mean that LED lighting is the traditional nemesis.
Insiders recently put forward in the micro-Bo: “Do not be seen with the traditional lighting and LED are simpler alternative relationship, not separated, if do so, it would ruin the LED lighting industry. LED lighting is the traditional relationship between inheritance and development, we should use this way of thinking starting from the LED light source combined flexible features to find the most suitable arena to shine. Only from the “alternative” perspective, LED light and lighting is naive and superficial performance. “
In the early 1990s, LED for cars and trucks brake lights. Some LED design soon emerged inconsistencies performance indicators, and quickly burned down, the reason may be due to the LED quality problems, perhaps the design of the product itself is entirely the problem. Until recently, in respect traffic lights, when the LED light source to become more appropriate, this phenomenon was only seriously. Design covered with a diameter of 8 inches or LED 12-inch PCB companies must choose the LED and improve the design and other aspects to consider environmental and application needs.
How to apply high-quality LED lighting
Any of the above circumstances, if the pressure test or accelerated life cycle tests have been done, it can be considered high-quality LED or LED assembly is qualified, it can be applied to a longer life and higher reliability occasions it.
Not every application requires high quality LED assembly technology. If the LED assembly does not meet the requirements of harsh environments, the application will not necessarily a larger security risk, or, if the final product is not very high maintenance costs, the use of some poor assembly techniques may be more appropriate.
The most fundamental point is the LED must be able to afford. Therefore, within the limits of the cost requirements, we must consider the level of vendor product packaging, assembly and testing of design experience and other factors. Meet the application and market demand is designed to serve the end user the most effective means. If the application requires high-end solution, then the chip vendor selection, design experience, and testing are all factors to be considered. If you do not consider the high-end product sales price, you should carefully consider the difference between good and bad LED and other relevant factors. Have the ability to classify the packaging level LED suppliers, and the ability to carry out reliability, accelerated life cycle testing vendors be able to conduct long-term cooperation, which helps manufacturers to adopt a more reliable LED develop high-end products.
Most designers think all LED lighting product quality is the same. However, LED manufacturers and suppliers many Asian manufacturers to global supply cost of the LED. Surprisingly, in these manufacturers, only a few can produce high-quality LED. For indicative only as a simple application, low-quality LED is sufficient to meet the requirements. However, in many of the requirements consistency, reliability, solid-state lighting and other areas of instruction or must use high-quality LED, especially in harsh environments, such as highways, military / aerospace, and industrial applications.
In the New York subway station environment, security requirements are very demanding, LED must meet the quality requirements of fundamental factors.
Distinguish between high and low quality LED factor is what? How to tell the difference between two kinds of LED? In fact, the selection of high quality LED chip can begin until assembly is complete, during which there are many factors to consider. Tier-One LED manufacturing company to produce good, consistent indicators wafer is manufactured from high-quality LED material humble beginnings, in turn, can produce excellent chip. LED performance in determining the conditions of all, the wafer used in the production process is a very important chemical material factor.
A 2 in. wafers can be cut out of more than 6000 LED chips, there is only the individual and the overall chip performance indicators are different. And an excellent chip makers manufacture chips in color, brightness, and other aspects of the voltage drop difference is very small. When the LED chip package is complete, the performance of many of their great differences may exist, such as the viewing angle. In addition, the impact of packaging materials is quite large, for example, than the epoxy silicone performance.
Classification ability
LED manufacturers excellent quality can be manufactured not only of the chip, and also has a color based on the LED luminance, voltage drop and angle to classify the different packaging capabilities. High quality LED vendors to provide customers with consistent product performance characteristics, while lower-quality LED suppliers can only offer similar to the “mixed” of the LED.
For the high-end, quality demanding applications, such as runway edge lights, must meet FAA specifications color and brightness level, to ensure performance and safety, LED packaging consistency and it was strictly limited. Packing LED is used in less demanding applications will lead to premature failure of a series of non-conformance issues, is likely to lead to a major accident. To avoid equipment downtime and ensure that the design requirements of the LED with a reliable operating characteristics, and the strict quality requirements of high-end applications avoid the use of “mixed” product is very important.
high-quality LED lighting equipment
Products supporting capacity
In addition to discrete LED, LED assembly and power supply for its performance, brightness and color indicators have a very significant impact. The ambient temperature, the operating current, the circuit structure, so the voltage spikes and environmental factors can influence the performance of LED, proper circuit design and assembly is to protect the LED and ensure the performance of the key. LED manufacturers can use a variety of techniques and different materials to design the circuit structure and assembly, in most cases, LED assembly difference in the experience of the level of the same application will cause the LED in the overall performance and reliability differences.
With the rapid growth in demand for LED, serve the global market manufacturers and assembly plants also increased rapidly. Unfortunately, the surge in support for manufacturers not only a large number of low-quality LED, their packaging and LED design engineers relative lack of experience. Therefore, in addition to the existing experience and accurate screening through LED suppliers outside, OEM manufacturers must also examine their circuit design and assembly techniques to ensure that it meets design specifications, and design provides adequate cooling capacity, because causes the LED failure and performance The main factor is inconsistent overheating.
To ensure that it meets the design requirements, OEM must detect the LED assembly and circuit structure.
LED lamps outstanding advantages are:
1, energy saving, LED luminous light efficiency, incandescent light efficiency is 15-20LM / W, LED lamps with high luminous efficiency can reach 60-100LM / W; That traditional 60W incandescent lamp with a 10W or so LED lamps can be replaced; LED fluorescent lamps are also compared with about 20% energy saving.
2, environmental protection, LED is a semiconductor device, do not contain mercury and other heavy metals materials; traditional energy-saving lamp manufacturing process and the use of waste mercury pollution, LED lighting energy saving lamp manufacturing process and use of process does not produce mercury pollution.
Advantages and disadvantages of LED lamps
3, long life, LED theoretical life of 100,000 hours, and is currently better quality life of 25,000 hours LED lamp warranty, incandescent lamp life of 1,000 hours, the fluorescent lifetime is more than 7000 hours.
4, high color rendering index, which is the color reproduction and high.
5, LED is a DC-driven, more suitable for solar lamps, solar panel life of 10-15 years, with a fairly long life of the LED general lighting maintenance costs will come down a lot; avoid the frequent replacement of light caused by maintenance costs.
Disadvantages of LED lamps
1 high cost, the current LED lighting gradually into the field of commercial lighting, LED lamps for general lighting manufacturing cost reasons in the field of large-scale application needs time.
2 LED constant current drive power required, the power of life affect the overall lamp life is one, if the LED power supply replacement is more convenient, you can overcome the power of the overall impact of lamp life.
Statistics showed that in the procurement of the LED when the reader is based on the brightness of the main selection and prices, both of which votes were 24.63%, occupy absolute advantage. In the second tier is the life and the light fades, respectively 17.91% and 15.67% of the readers’ poll. Finally, the thermal resistance of the winning rate was 3.73%
How much power LED products will become the mainstream market it? Readers comments are not the same: 37.31% of the readers chose 1W power LED, that it will make future market mainstream models; followed 3WLED, about a quarter of the reader’s vote (26.12%); 0.5W and two kinds of power 5W LED products relatively few people chose the winning rate was 11.19% and 13.43%, 0.2WLED minimum percentage of votes, only 9.7%.
LED lighting applications market can be broadly divided into outdoor lighting, indoor lighting, and backlighting three parts. After statistics, the reader in mind in the future LED lighting market is the most important indoor lighting, more than half of the readers (51.49%) chose this option. Outdoor lighting and backlighting supporters were only 29.85% and 11.19%. Warm white LED light is being more and more people of all ages, our findings also confirm this statement: up to 62.69% of the readers with absolute advantage will warm white LED onto the top spot, and become the main trend of demand for LED lighting ; cool white LED also has a certain market, accounting for 26.12%; while the blue LED color applications such as only a small part of the vote was only 9.7%.
2010 LED prices go up or down? Apart from a few readers that will rise (21.64%) or flat (2.24%), the vast majority of readers have chosen the decline, but the decline in the amount of disagreement on the issue there: 35.82% of readers believe that prices will fall this year, LED 10 to 30 percent, becoming the most majority opinion; 29.1% somewhat conservative readers that decrease below 10%; addition, about 10.45% and 0.75%, respectively, expressed support for the readers of “down 30% to 50%” and ” more than 50% “in two bold speculation.
What are the reasons hindering the development of LED lighting market? The findings show that the cost factor is the question we are most concerned about, expensive price as many practitioners must challenge; cooling issues are also part of the reader more concerned, about 26.12% of readers think they encountered a bottleneck in the heat treatment; There are also product standard is not perfect (18.66%) and other problems should be solved.
LED high bay lights are widely used in workshop, factory, warehouse, highway toll stations, gas stations, supermarkets, exhibition halls, stadiums and other needs of industrial lighting.
LED High Bay Lights are installed in what occasion
As we all know, the lighting energy consumption occupies a important part of the complete energy consumption. For example, in a 40,000 square meters factory buildings, lighting load is about 400KW, therefore, the choice of lighting in the factory, how to achieve energy saving, environmental protection is placed in the plant designers an important issue. Using new LED light source based LED High Bay Light, in addition to energy saving, it also has a long life, fast response time, pure light color light concentration, etc., in recent years, well received by consumers.
Mining lamps are widely used in factories, warehouses, supermarkets, fruit shops and other large areas that require high intensity lighting. They can directly replace the traditional E40 lamp holder fixture interface, easy installation and maintenance.
The decorative effect of LED High Bay Light is excellent, with a special surface treatment process, appearance can choose a variety of colors, simple installation, easy disassembly, apply a wide range.
LED High Bay light uses constant current control for wide voltage generated by the ballast to overcome the power grid, noise pollution and unstable light caused, to avoid the work to bring eye irritation, fatigue.
The color rendering of LED High Bay Light is good and more than real. Variety of light colors optional, to meet the different needs of the environment, eliminating the traditional lamp color depression caused by high or low mood, the visual department comfort, improve worker efficiency.
Use of lighting performance characteristics of the object itself, it can be natural objects or scenic spots, it can be ancient buildings or modern buildings.
LED lights how to show characteristics of the building
Monumental architecture: monumental architecture are some of the artistic, aesthetic features of the building, such as Buckingham Palace in London, France Arc de Triomphe and the Eiffel Tower, the Statue of Liberty in New York and Beijing bronze statue of Chairman Mao Memorial Hall, People’s Heroes Monument, Great Hall, etc., night lighting so that they, too majestic.
Neighborhood: main plaza surrounding the pavement lighting, showcase lighting, advertisement sign lighting and street lighting integrated static and dynamic combination of shapes, three-dimensional staggered, colorful, have shown a bustling scene, thereby increasing vitality .
Art View: Landscape Art based on a variety of raw materials or materials created objects, there are purely decorative role, such as statues, reliefs, gatehouse and some of the landscape, such as listening to music, to these landscapes to decorate or embellishment space, night lighting more students Hui.
Water View: eg fountain, fountains, wells and artificial lakes, etc., they and lighting combine to create a more attractive scenery. Square has marked sexual landscape, trees, drain fill plants, lawns, flower stalls, etc., so that it formed a certain scale, a create a magnificent night.
Building is the city’s landscape, lighting and build a second city skyline. Modern city due to the unique geographical landscape and cultural environment, and their respective aesthetic ideas and shapes, different styles of architecture in the light next to do now decorate its grand and imposing, and strengthen the city’s unique image, and thus play the iconic landscape value.
Beautiful urban landscape lighting not only for the people to create a good nocturnal lighting environment, enrich people’s nightlife, but also for economic prosperity, the development of the tourism industry, especially for propaganda achievements of China’s reform and opening up and thriving excellent situation, establish and the performance of a region or city at night image so has important significance and impact.
Has great potential for development as a light source, LED’s long life, rugged construction, low power consumption and flexible dimensions, etc. by the people more and more attention in recent years, LED especially monochrome LED is widely used in large-screen, lights and landscape lighting. As LED technology continues to evolve, the white LED luminous efficiency, color rendering, color temperature and a single LED power and luminous flux LED module parameters such indicators continue to achieve new breakthroughs, people are looking forward to LED for lighting.
White LED lights for indoor lighting application
However, the white LED used in ordinary indoor lighting is also facing a number of challenges, such as single LED luminous flux is also difficult to meet the demand for general lighting, the unit cost is too high, the low light efficiency than energy-saving lamps, great color, stability is inadequate. Although research is gratifying, but to truly meet the lighting requirements to produce market-oriented products will take some time, which is LED R & D personnel, manufacturers and users inescapable fact. In this paper, lighting ergonomics, analyzes the current situation and development of white LED light environment and health indicators required for the normal difference between the promotion of LED interior lighting application process made some suggestions.
1, lighting ergonomics
Ergonomics Ergonomics is also called ergonomics or to “man – machine – environment” system as the research object, using measurement, statistics, analysis and other methods to study the “man – machine – environment” between the three elements of the system relationships to solve the system of human performance, health problems. In other words, ergonomics research dedicated to the design and * price of human needs, human capacity, human limits, and how various tasks, jobs, products, environments and systems coordination. Lighting ergonomics, is the study of how the design of light environment to meet human needs, to make people better and faster completion of the visual task or try to meet the needs of a comfortable and healthy.
Illumination environment should take full account of the needs of visual function to meet people, so that people can fit in a visual environment to work properly, which can be clearly seen; psychological needs but also to meet people that want to see comfortable. A recent study showed that light can affect the human body through the secretion of melatonin affect the body’s circadian rhythms and health. Therefore, considering the ergonomics of the environment should be good light from human vision, psychological and physiological needs, a number of factors into account, otherwise it will on people’s working efficiency, psychological or physiological cause adverse health effects.
2, white LED current development
2.1 light efficiency
LED since its inception in the 1960s, in order to improve the brightness of every 10 years, 30 times, 10 times lower prices “Hydes Law”-like pace. According to reports, the current white LED luminous efficiency of laboratory data has more than 100lm / W, and into the commercial area of ??high-power white LED has reached 40lm / W. With breakthroughs in key technologies, the future high-power LED light effect still has much room for growth, the highest may reach 150 ~ 200lm / W.
2.2 Flux
With the advent of high-power LED and packaging, cooling and other key technology breakthroughs, 5WLED commercialization process has taken shape, which makes the flux LED module has been greatly improved. From Nichia’s latest research data shows that power was 5.5W and 11W, respectively 250lm and 400lm luminous flux of high-power LED integrated module has been developed. This makes LED for general illumination process forward in a major step forward.
2.3 color temperature and color rendering
White LED color temperature and color rendering with white LED is closely related to the preparation of solutions. 1996 first used Nichia InGaN blue chip plus YAG (yttrium aluminum garnet) $ phosphor method for producing white LED. Since then, people using R, G, B three color chips mixed excitation light and near ultraviolet chip R, G, B three-color phosphor powder mixed light into the white LED.
Blue LED using YAG phosphor way plus its process is simple, low cost technique, preparation of white LED is the most common way, but its color rendering index is relatively low. Add some red and green phosphor phosphor can improve the color rendering index, though, but because of the red phosphor relatively low conversion rate, usually caused by the overall flux attenuation, namely light efficiency decline. Near-ultraviolet LED plus RGB trichromatic phosphor can theoretically get any color temperature and high color rendering index white LED, but for UV LED phosphor technology is not yet mature. Single-chip phosphor coating method of the phosphor coating techniques, it is generally 80 ~ 800K with a color temperature difference. Multi-chip LED is theoretically possible to get any color temperature and high color rendering white LED, but due to multi-chip LED forward voltage and light output are different, in addition they maintain the temperature characteristics and properties of light is not the same, and thus the circuit design requirements is higher, the current technology is not mature, large differences between modules color temperature.
3, considering the ergonomics requirements for white LED lighting
As previously described, considering illumination ergonomics people consider the lighting environment. Indoor environment for people living and working environment stays most of the time, so people on the indoor lighting needs of the environment is getting high. Can meet these requirements, the LED light source instead of traditional interior lighting of the key.
3.1 visual function needs
In order to meet people’s visual needs, namely to make people able to see clearly, which requires illumination environment with a certain level of illumination, illumination uniformity and color rendering.
To meet certain level of illumination, the LED requires a sufficient flux. Reading room with a small example, assume reading area 6m × 8m, then about 20000 ~ 30000lm flux in order to meet people’s normal reading. Without considering other factors, the application of high-power currently on the market 200lm particles 100 to 150 particles also need to be able to reach such an LED illumination requirements. Due to the current market products better light efficiency at 30 ~ 40lm / W or so, whether energy or cost, LED and energy-saving lamps can not compete or fluorescent. In addition, LED lighting optical design technology immaturity make the current LED lamps light distribution is not stable enough to reach a certain uniformity of illumination also requires a very high cost. However, a small area of focus for the lighting of the LED with a small power consumption to meet the visual needs, uniformity also relatively easy to meet. In terms of color, white LED current can basically meet the general needs of indoor activities.
3.2 psychological needs
In normal indoor work or activity, it requires not only get the satisfaction of visual function, but also requires a certain visual comfort, this is the people’s psychological needs illumination light environment, it requires the field of view can not have direct glare light environment or indirect glare, color temperature to the right, lighting layout should be comfortable. In the field of view requirements glare of white LED are both advantages and challenges. As the LED light point and a small beam angle, the light emission direction is easy to control, but on the other hand, the LED light intensity generally more concentrated at the maximum light intensity distribution is easily if mishandled to cause glare to the observer. Studies have shown that not only cause discomfort glare efficiency decline, but also cause visual fatigue and headaches and other adverse reactions. In addition, if the choice of RGB three-chip LED, although able to form any color temperature of white light, but the larger the field of view of the color difference will affect the overall comfort and aesthetics. If the selection of YAG powder blue LED plus the way, the basic color temperature is high. In order to have a good effect of the illumination, the color temperature of the light source must be selected and adapted to the requirements of illumination, Figure 1 shows the illuminance and color temperature corresponding to the comfort zone. Therefore, the higher the color temperature can also affect white LED interior lighting applications, because it requires a high illuminance appropriate to make people feel comfortable. On the other hand, LED flexible dimensions that LED lighting has been designed with a lot of space, we can fully meet the decorative requirements.
3.3 physiological needs
Indoor lighting people on physiological needs mainly for health needs. In addition to long-term UV radiation can cause skin adverse effects other than light affect the health of the other two ways are often overlooked by people, is a light through the visual impact on health, and the other is light through the circadian system affect health. With white LED for indoor lighting has two effects is closely associated retinal blue light through the hazardous effects and suppress the body’s secretion of melatonin circadian rhythms affect the body systems and health. UV damage usually occurs before the eye portion of the human eye, which can cause damage to the cornea. The Blu-ray because of its longer wavelength than UV light can reach the retina through a fundus; while the unit of energy in the visible range of the strongest, easy to burn the retina and the early formation of cataracts. On the other hand, the body’s secretion of melatonin by light effects, when melatonin secretion disorders is likely to cause confusion in the human circadian rhythm, cause cancer or other serious diseases.
In the region of 400 ~ 500nm, the energy distribution of this white LED has a distinct peak. Added after a certain amount of red phosphor can be reduced to some extent this peak, but the current widespread use of white LED and blue peaks of the blue region of the spectral sensitivity curves of retinal damage and affect the circadian rhythm system ganglion cells sensitivity to light curves have more overlap area, which can not but arouse our attention. And if using a UV LED and RGB trichromatic phosphor plus multi-chip white LED, these two effects can be ignored.
4, to promote white LED interior lighting applications
High-power white LED light effect though, the color and the single power has made great breakthroughs in the LED manufacturers are also constantly updated rapid momentum has been achieved. However, taking into account the ergonomic aspects, for the need to create a line with the Habitat lighting environment, LED is clearly still a long way to go. In order to promote LED more and more reasonably applied to indoor lighting, the following aspects are LED designers, producers and the users should be of common concern.
4.1 the importance of appropriate lighting design
Needs in terms of visual function, LED luminous flux and luminous efficiency is also difficult to meet the needs of a large area of ??general lighting. Thus, reasonable lighting design is applied to the LED interior lighting of the key. For example, the partial use of LED accent lighting, or the use of easy to control the characteristics of LED auxiliary lighting and dimming design. Design should be combined with visual function, psychological and physiological needs, weaknesses, creating a healthy and comfortable light environment.
4.2 emphasis on the LED, midstream and downstream of the close contact
Undoubtedly, LED on the upper and middle reaches of the development and application of LED technology has played a key role, but the downstream applications and demand for the LED also play a leading role on the middle reaches. Scientists, engineers, and designers should strengthen ties, the LED industry development more rational and humane.
4.3 Strengthening LED secondary optics design technology
LED lighting applications, a key technology is the LED secondary optics design technology, through the secondary optical design, to optimize the LED light distribution, while avoiding glare emitted from the LED light is more reasonable to achieve the lighting requirements.
With the city’s economic construction and the rapid development of transportation, urban construction as the increasing number of large scale and lighting, urban lighting electricity consumption is also rising rapidly. How to meet the city residents and visitors from all live and work requirements, to meet the traffic safety, traffic smoothly under the premise of promoting low-carbon economy, promote green lighting. In urban road lighting, scientific and rational energy saving has become an important topic. This article on this subject to talk about their experiences.
City lights energy-saving technology
First, the appropriate illumination
In our city road lighting energy-saving work, proper illumination is the first to attention. We want to follow, “city road lighting design standards” CJJ45-2006 standards, according to the nature and scale of urban roads, for urban road lighting design. Meet the requirements of a variety of lighting standards proposed design, undertake a comprehensive technical and economic analysis and comparison, to choose the technology advanced, economical and optimum road illumination energy conservation values ??and lighting power density values. Not be divorced from “urban road lighting design standards”, one-sided pursuit of brightness, the pursuit of beauty, the pursuit of luxury.
Second, the capacitance compensation
The main city road lighting source is a gas discharge lamp, the starting current, the power factor is low, generally 0.45 or less, this will result in large current loops on the line to generate more losses. “Urban road lighting design standards” requirement should be added to the gas discharge lamp capacitor compensation, power factor compensation shall not be less than 0.8. However, the standard does not explicitly single lamp is concentrated dispersion compensation or compensation. Currently two kinds of compensation capacitors are in use. I think, as street lighting facilities are evenly distributed on both sides of the road, by the power to low voltage wiring long street lamps, road lighting system produces losses mainly occurred in this period, the use of lights at centralized power compensation, does not reduce the pressure power wiring. The use of a single light dispersion compensation, will undoubtedly reduce the lamp power to the lamps which generate a loss on the line, will play a good energy-saving effect.
Third, the implementation of control at midnight
Turn off the light source at night half way direct and significant energy-saving effect, saving operation time saving up to 50%, overall about 30% or so. Currently, the city control method commonly used in the night, to take “every one bright one” or “bright one every two” measures, the closure of some light, energy-saving effect is very obvious. However, the use of “bright one every one” or “one every two bright” mode, it will cause bad road illumination uniformity. Unilateral cloth lamps, light sources should not promote close half way. If you choose this approach, the disparity between light and dark lanes late at night, illumination uniformity is far below the design standards. In practice, I believe that the program can be double light fixtures, two light sources such as power or unequal power available. With this cloth lamp options, ShangBanYe two full bright light, late at night close one source. In this way, the control uniformity had no effect, unilateral arrangement, staggered, symmetrical arrangement, can use this program.
Fourth, intelligent light buck – Regulators – dimming technology,
Intelligent Light buck – Regulators – dimming technology, the device is installed in the power distribution circuit Qiduan street in before midnight for the whole loop pressure control the lights, close to midnight, the car came from a lower voltage thin people. Its saving principle there are two, one is to maintain high pressure sodium lights voltage below 198V, the light will not be extinguished; second is due midnight grid users less load is low, the grid voltage higher than 220V, and overvoltage an additional portion of energy consumption, the use of this device is to avoid this part of the waste. According to engineering practice, and its energy-saving effect in about 15%. With this device, not only saves energy, does not affect the uniformity of illumination, but also to avoid light overpressure run, extending the life of electrical light source. It should be noted that this method is a step-down power distribution circuit, within the circuit all fixtures in the low-voltage operation. As street distribution circuit supply radius up to 800 meters, with the lamp and power supply terminal distance increases, the voltage gradually decreased, if the lines are poorly designed, there may be a remote voltage source can not meet the normal maintenance of the required voltage.
Five, using variable power ballast
Variable power ballast, use gas discharge lamp in proper operating current is reduced, the principle still running through the rest of the night to increase ballast reactance, thereby reducing the source current to achieve the purpose of energy saving street lighting system as a whole. In this way because it is installed at the lamp, can be applied to a variety of lamps and lamp combination arrangement. The original road lighting engineering, may also have additional type variable power ballast transformation, supporting the original lamp ballasts shall not replace, convenient transformation of the construction, and reduce system cost.
