The EL tester is a device specially designed to test the power generation efficiency of photovoltaic modules. Through the EL tester, we can understand the performance and quality of the PV module, ensure that it works properly and achieves the expected power generation effect. This article will introduce the basic principles and test methods of EL testers, as well as the main factors that affect the power generation efficiency of photovoltaic modules.
1. The principle and test method of EL tester.
The EL tester uses the principle of electroluminescence to excite fluorescence by applying a forward voltage to the surface of a photovoltaic module to redistribute the carriers inside it. This fluorescence can be captured by the camera and formed into an image, which can be analyzed to understand the performance and quality of the PV module.
The test method consists of the following steps:
1.Place the PV module under test on the test bench and connect it with the EL tester.
2.A forward voltage is applied to the surface of the PV module to redistribute its internal carriers.
3.A camera is used to capture fluorescence images of the surface of a photovoltaic module.
4.Analyze images to obtain information about the performance and quality of PV modules.
2. Factors affecting the power generation efficiency of photovoltaic modules.
1.Illumination intensity: Illumination intensity is one of the most important factors affecting the power generation efficiency of photovoltaic modules. At a certain light intensity, the output power of photovoltaic modules increases with the increase of light intensity. Therefore, in order to improve the power generation efficiency of photovoltaic modules, it is necessary to select the appropriate light intensity area for installation and use.
2.Temperature: Temperature is also one of the important factors affecting the power generation efficiency of photovoltaic modules. Within a certain temperature range, the output power of photovoltaic modules decreases as the temperature increases. Therefore, in order to improve the power generation efficiency of photovoltaic modules, it is necessary to keep them operating in the appropriate temperature range.
3.Shadow occlusion: When the surface of a PV module is shaded, it will seriously affect its power generation efficiency. Therefore, it is necessary to avoid shadow occlusion in practical use, or take appropriate measures to reduce its impact.
4.Series matching: When multiple PV modules are used in series, due to the possible differences in the performance parameters of each module, some modules will be overloaded or underloaded, which will affect the overall power generation efficiency. Therefore, it is necessary to ensure that the parameters of each component match in actual use.
5.Surface fouling: Surface fouling of PV modules can affect the absorption and reflection of light, thus affecting their power generation efficiency. Therefore, the surface of the PV module needs to be cleaned and maintained regularly to maintain its cleanliness.
6.Installation angle and height: The installation angle and height of a PV module will also affect its power generation efficiency. In actual use, it is necessary to choose the appropriate installation angle and height according to the local climatic conditions and geographical location.
7.Aging: Over time, the performance parameters of PV modules may change, resulting in a decrease in their power generation efficiency. Therefore, PV modules need to be regularly inspected and maintained to ensure that they are working properly and that their service life is prolonged.
To sum up, the EL tester is an important testing equipment that can help us understand the performance and quality of photovoltaic modules. In actual use, we need to comprehensively consider various factors to improve the power generation efficiency of photovoltaic modules and achieve sustainable energy development.