1、Advancements in Solar based LED Street light Nupur 1 Neha 1 Sangya gugri 1 Srishti mishra 1 Gulshan kr. dubey 2 UG Student, Dept. of EIE, Galgotia s College of engineering & technology, Uttar Pradesh India 1 Associate professor, Dept. of EIE, Galgotia s College of engineering & technology, Uttar Pra
2、desh, India 2 ABSTRACT: We are in the time where energy conservation & use of renewable resources has become a necessity. Thus requirement of methods which are not only highly efficient but also low in energy consumption has greatly increased to keep a check on pollution factor. Keeping this in mind
3、 this paper focuses on solar based LED street light that uses automatic intensity controller with a solar tracker. This type of LED street light not only adjust itself according to the varying darkness but also keeps a track on overcharging, deep discharging, automatic restoration of charging ,prote
4、cting the battery from the over/under voltage. It comprised of solar cell and electric energy stored from battery. The LED street lamp is lit at night automatically and changed into pulsed lighting in low power after the setting time and then turns off in daytime. Since only 20% of the total sun s e
5、nergy falls on earth and also the trajectory of sun keeps changing thus a solar tracker is used so as to track maximum sun s energy. Keywords:Solar panel, charge controller, Intensity regulator, Solar tracker. I.INTRODUCTION Thesurface of the Sun has a temperature of about 5,800 Kelvin (about 5,500
6、degrees Celsius, or about 10,000 degrees Fahrenheit),as per the say of NASA, At that temperature, most of the energy the Sun radiates is visible and near- infrared light. At Earth s average distance from the Sun (about 150 million kilometres), the average intensity of solar energy reaching the top o
7、f the atmosphere directly facing the Sun is about 1,360 watts per square meter, according to measurements made by the most recent NASA satellite missions. This amount of power is known as the total solar irradiance. (Before scientists discovered that it varies by a small amount during the sunspot cy
8、cle, total solar irradiance was sometimes called “the solar constant.” Averaged over the entire planet, the amount of sunlight arriving at the top of Earth s atmosphere is only one-fourth of the total solar irradiance, or approximately 340 watts per square meter. II. SOLAR TRACKER Solar tracking sys
9、tem1 is the most appropriate technology to enhance the efficiency of the solar cells by tracking the sun. A microcontroller based design methodology of an automatic solar tracker is presented in thispaper. Light dependent resistors are used as the sensors of the solar tracker. The sun is the prime s
10、ource of energy, directly or indirectly, which is also the fuel for most renewable systems. Among all renewable systems, photovoltaic system is the one which has a great chance to replace the conventional energy resources. Solar panel directly converts solar radiation into electrical energy. Solar p
11、anel is mainly made from semiconductor materials. Si used as the major component of solar panels, which ismaximum 24.5% efficient 2. Unless high efficient solar panels are invented, the only way to enhance the performance of a solar panel is to increase the intensity of light falling on it. Solar tr
12、ackers are the most appropriate and proven technology to increase the efficiency of solar panels through keeping the panels aligned with the sun s position. Solar trackers get popularized around the world in recent days to harness solar energy in most efficient way. This is far more cost effective s
13、olution than purchasing additional solar panels 3. III. TECHNOLOGY TO ENHANCE POWER OUTPUT FROM SOLAR PANEL Increasing the cell efficiency, maximizing the power output and employing a tracking system with solar panel are three ways to increase the overall efficiency of the solar panel4. Improvement
14、of solar cell efficiency is an ongoing research work and people throughout the world are actively doing research on this. Maximizing the output power from solar panel and integrating solar tracking system are the twoways where electronic design methodology can bring success. Maximum power point trac
15、king (MPPT) is the process to maximize the output power from solar panel by keeping the solar panel s operation on the knee point of P-V characteristics. A number of MPPT algorithms have been developed and employed around the world 5. MPPT technology only offers the maximum power that can be receive
16、d from a stationary array of solar panels at a particular time； it cannot, however, increase the power generation when the sun is not aligned with the system. Automatic solar tracker increases the efficiency of the solar panel by keeping the solar panel aligned with the rotating sun. Solar tracking
17、is a mechanized system to track the sun s position that increases power output of solar panel 30% to 60% than the stationary system 6. A few design methodology of solar tracking system has been proposed in recent days 7-9. LED (Light Emitting Diode), light-emitting Diode, is a kind of ability to ele
18、ctric energy into visible Light solid state semiconductor devices, it can be directly put DianZhuan into Light. The heart of the LED is a semiconductor chip, chip attached on a bracket, at the end of the end is negative, the other end connected to the power of the anode, the whole chip is encapsulat
19、ed by epoxy resin. Semiconductor chip consists of two parts, one part is a p-type semiconductor, dominated by holes in it, the other end is n-type semiconductor, here is mainly electronic. But this two kinds of semiconductor connected, forming a p-n junction between them. When a current flows throug
20、h a wire to the chip, the electron will be pushed P area, electron and holes in the P zone compound, then will be issued in the form of photon energy, this is the principle of LED light. And the wavelength of light was the color of the light, is determined by the formation of p-n junction material.
21、Initially LED is used as the indicator light instrument and then all kinds of light color of LED traffic light and display screen has been widely applied in large area, produced good economic and social benefits. 12-inch red traffic lights, for example, in the United States could have been used long
22、 life, low light efficiency of 140 - watt incandescent lamp as light source, it produces 2000 lumens of white light. After the red filter, light loss 90%, only 200 lumens of red light. And in the light of the new design, Lumileds companies adopted 18 red LED light source, including circuit loss, tot
23、al power consumption of 14 watts, can produce the same light. Car light is also an important field of LED light source. For general lighting, people need more white light sources. Hair white light LED successful development in 1998. This LED to GaN chip and yttrium aluminum garnet (YAG) packaging to
24、gether. GaN hair blue chip (lambda p = 465 nm, Wd = 30 nm), high temperature sintering of YAG phosphors containing Ce3 + yellow light shot after the blue light excitation, peak 550 m nled lamp. Blue LED substrate is installed in the bowl reflection cavity, covered with thin layer of resin mixed with
25、 YAG, about 200-500 nm. LED substrate from the blue part is absorbed phosphor to another part of the mix blue with yellow light from fluorescent powder, we can get more white light. For InGaN/YAG white leds, by changing the chemical composition of YAG phosphors and adjust the thickness of phosphor l
26、ayer, can obtain a variety of white light color temperature 3500-10000 k. This by the method of blue leds for white light, simple structure, low cost, high technical maturity, so use the most. Compared with the traditional glow of light, LED light source is low pressure microelectronics products, su
27、ccessfully combines computer technology, network communication technology, image processing technology and the embedded control technology, etc. Traditional LED lights used in the chip size is 0.25 mmX0.25 nm, and the size of the LED lighting is typically mmX1.0 in 1.0 mm and above. LED bare chip fo
28、rming work table structure, the inverted pyramid structure and flip chip design can improve the luminous efficiency, thus more light. LED packaging innovation including the design of high conductivity metal base, flip chip design and bare plate casting type lead frame and so on, these methods can de
29、sign a high power, low thermal resistance of the device, and the device of the illumination intensity of illumination is greater than traditional LED products. A typical high flux LED device can produce several lumens to dozens of lumen flux, update the design can be integrated in a device more leds
30、, or multiple devices can be installed in a single assembly, so that the number of lumen output is equal to the small bulb. For example, a high power 12 monochromatic LED chip light energy device can output 200 lm, the consumed power between 10 15 w. The application of LED light source is very flexi
31、ble, used as the dot, line, face various forms of lightweight products； LED control is extremely convenient, as long as adjust current, can be arbitrarily adjusted light； A combination of different light color changing, the sequential control circuit, can achieve more dynamic change of rich and colo
32、rful effect. LED has been widely applied in all kinds of lighting equipment, such as a battery-powered flashlight, mini voice control lamp, security lighting, outdoor and indoor stair floodlight roads and buildings and tag continuous lighting. The emergence of white LED is LED from the identificatio
33、n to the illumination function across a substantive step. White LED closest to the sun, more can well reflect the reality of the irradiation object color, so from a technical perspective, white LED is undoubtedly the most cutting-edge LED technology. White LED has began to enter some application fie
34、ld, emergency lights, flashlights, flash and other products appeared, but because the price is very expensive, so hard to popularize. White LED popularization is the premise of price decline, and prices must be formed in the white leds is possible after a certain market scale, integration of the two end depends on technology progress. IV. MICROCONTROLLER The ATMEGA32 microcontroller has been used in the prototype. Microcontroller is the heart of overall system.ATMEGA32 microcontroller requires a 5 volt regulated voltage supply. 7805
