Solar LED lighting system technologies and engineering design
The Solar LED lighting is a practical knowledge website that organically combines the design of LED solar lighting system with lighting technologies engineering application
1. Luminous flux Luminous flux Φ is the radiant energy that characterizes the total light output of the LED, and it marks the performance of the device. Φ is the sum of the energy that the LED emits in all directions, and it is directly related to the working current. As the current increases, the…
The light emitted by the LED is not a single wavelength, and its wavelength is basically distributed as shown in Figure 1. It can be seen from Figure 1 that no matter what material is used for the LED, the spectral distribution curve of the LED has the strongest relative light intensity (the maximum light…
The luminous intensity of an LED is a characterization of its luminous intensity in a certain direction. Since the luminous intensity of the LED differs greatly in different spatial angles, it is necessary to study the luminous intensity distribution characteristics of the LED. This parameter is of great practical significance and directly affects the secondary…
1. I-V characteristics. The I-V characteristic is the main parameter that characterizes the performance of the PN junction of the LED chip. The I-V characteristic of the LED has nonlinearity and unidirectional conductivity, that is, the applied positive bias voltage is low resistance, and vice versa, it is high resistance, as shown in Figure 1….
The luminous efficiency of the LED is generally called the external quantum efficiency of the module, which is the product of the internal quantum efficiency of the module and the extraction efficiency of the module. The so-called internal quantum efficiency of a module is actually the electro-optical conversion efficiency of the module itself, which is mainly related to…
LED is made of III-V compounds, such as GaAs (gallium arsenide), GaP (gallium phosphide), GaAsP (gallium arsenide phosphorous) and other semiconductors, and its core is a PN junction. Therefore, it has the I-V characteristics of a general PN junction, that is, forward conduction, reverse cutoff, and breakdown characteristics. In addition, under certain conditions, it also…
People have understood the basic knowledge that semiconductor materials can produce light 50 years ago, and the first commercial diode was produced in 1960. The structure of LED is mainly composed of PN junction chip, electrode and optical system. When a forward bias is applied to the electrode, electrons and holes are injected into the…
The output characteristic curve of the solar cell module is shown as in Figure 1. It can be seen from Figure 1 that the volt-ampere characteristics of solar cells have strong nonlinearity, that is, when the sunlight intensity changes, the open circuit voltage will not change much, but the maximum current generated will change considerably….
Only a small part of the light energy projected on the entire illuminated surface of the solar cell can be turned into electrical energy, because it is affected by many factors. The radiation of sunlight in outer space is basically constant, but after being absorbed by the atmosphere with different composition and thickness (It includes the…
A silicon atom has 14 electrons, which are distributed on three electron layers. The two electron layers inside have been filled, and only the outermost layer lacks four electrons to be half full. In order to achieve a stable structure of the full-electron layer, each silicon atom can only combine with its four adjacent atoms to…