Photovoltaic power generation is applied to solar lawn lights, street lights and LEDs

①Solar lawn light
Solar lawn lamp is a new type of green and environmentally friendly decorative lighting that is popular in Europe, America, Japan and other international markets. It uses solar cells to absorb sunlight to generate electricity to charge the battery in the lamp body. Automatic charging during the day and automatic lighting (light control) at night. The light uses 1 to 2 or more yellow, white, red, green, blue and other super bright LEDs. The battery can be charged continuously for 8~12h a day. The lamp body is made of high-strength ABS plastic, cast aluminum or high-quality steel. It is beautiful (can be designed and developed in many styles) and easy to install (insert it in the grass garden or install it in the door) The exterior wall is sufficient), strong decoration, energy saving, environmental protection, safety and trouble, low price, deeply loved by people. The solar lawn lamp is shown in Figure 1.

Figure 1 Solar lawn light

The working principle of the solar lawn lamp: during the day, when the sun shines on the surface of the solar panel, the solar cell generates electricity due to the photovoltaic effect. The electric energy is transmitted to the controller through the wire, and the controller detects the voltage condition of the battery to charge. At night, the sunlight gradually weakens, and the working voltage and working current of the solar panel gradually decrease. When the working voltage is less than the charging voltage specified by the controller, the discharge starts, and the discharge ends when the voltage generated by the solar panel is greater than the voltage specified by the controller the next day. This keeps circulating, which is the principle of light control of solar lamps.

The lawn lamp uses LED as the light source, and the LED has a long lifespan, which can reach 100,000h with a low working voltage, and is suitable for use in solar lawn lamps. The LED is powered by low-voltage DC, the light source control cost is low, it is easy to adjust the brightness, can be switched frequently, and will not adversely affect the performance of the LED; it can also easily control the color, change the light distribution, and produce a dynamic illusion, so it is suitable for use On the solar lawn lamp.

In general, low-power solar lawn lights below 1W have the functions of adjusting brightness and frequent switching, and generally use LEDs as the light source. However, when using ultra-bright white LEDs, attention should be paid to the problem of luminous efficiency, otherwise it will easily cause the quality of lighting to decrease. For large-power solar lawn lights, it is more reasonable to use three-color high-efficiency energy-saving lamps.

②Solar street light and LED
Solar street light is a kind of street light that uses solar energy as an energy source. During the day, solar panels charge the battery, and at night, the battery powers the light. Because it is not affected by power supply, does not require trenching, does not consume conventional electricity, and can be installed on the spot as long as the sun is sufficient, it has received widespread attention and is called a green product because it does not pollute the environment. Solar street lights can be used to illuminate urban parks, roads and lawns, and can also be used in areas with low population density, inconvenient transportation, underdeveloped economy, lack of conventional fuels, difficult to use conventional energy to generate electricity but rich solar resources, to solve these areas Home lighting problems.

The working principle of the solar street light: under the control of the intelligent controller, the solar panel absorbs solar energy and converts it into electric energy through the sunlight during the day to charge the battery pack; at night, the battery pack provides power to the LED to realize the lighting function. The intelligent controller can ensure that the battery pack is not damaged due to overcharging or overdischarging. It also has functions such as light control, time control, temperature compensation, lightning protection and reverse polarity protection. The structure of the solar street light is shown in Figure 2.

Figure 2 Solar street light structure

The solar street light system is composed of solar cell components, lamp caps (LED), intelligent controllers, storage batteries (including storage battery incubators) and light poles. Solar cell modules generally use monocrystalline silicon solar cell modules or polycrystalline silicon solar cell modules. LED lamp holders generally use high-power LED light sources. The controller is generally placed in a light pole, with light control, time control, overcharge and overdischarge protection, and reverse polarity protection. The advanced controller has the function of adjusting the lighting time in four seasons, the half power function and the intelligent charging and discharging function. In addition, it also has the function of automatically turning on and off the lighting. Usually, the timing and light control are used to control the working time of the solar street lamp. control.

The advantages of solar street lights are: solar street lights do not need to lay complicated and expensive power supply lines, so they can be installed in any site and any environment: its battery uses natural light and can be recycled without external power supply. It is green and environmentally friendly. When the sun is insufficient At a certain level, the solar street light can automatically adjust the switch, truly unattended, all-weather work; the solar street light is green, environmentally friendly, energy-saving and consumption-reducing, long service life, stable product structure, and has very good social and economic benefits .