The hot spot effect has a great impact on the performance of photovoltaic modules. In order to verify that the photovoltaic modules can be used for a long time under specified conditions, it is necessary to test the photovoltaic modules through a reasonable time and process to determine their ability to withstand the heating effect of hot spots. The hot spot durability tester is a test equipment used to determine the ability of photovoltaic modules to withstand hot spot heating. The equipment is usually composed of radiation source 1 (steady-state solar simulator, irradiance not less than 700W/m², instantaneous instability within ±5%), vehicle radiation source 2 (class C steady-state solar simulator or natural light , its irradiance is 1000W/m²±10%), a photovoltaic module IU curve tester, a set of opaque cover plates with a speed light increment of 5% for the test photovoltaic modules, and an appropriate temperature detector.
1. Hot spot durability test procedure
(1) Irradiate an unshaded component under irradiation source 1, first calibrate the irradiation intensity with a standard sample or standard component, and then test the /I-U characteristics and maximum power point of the component under test.
(2) Short-circuit the module, and the module is irradiated by a stable radiation source 1, and use an appropriate temperature detector to determine the hottest cell (3) Completely block the selected cell monolith, and irradiate the module with radiation source 2. The temperature of the components during this process should be 50°C ± 10°C.
(4) Keep this state after 5h exposure.
(5) Re-determine the /I-U characteristics and the maximum power point of the module.
2. Requirements for hot spot durability test
(l) The solar cell module has no serious appearance defects.
(2) The attenuation of the maximum output power of the solar cell module shall not exceed 5% of the test value before the test.