Photovoltaic module reliability detection method

Abstract

The invention discloses a photovoltaic module reliability detection method, which comprises the following steps: S1, removing a module diode, and arranging a thermocouple on a back plate surface; s2,externally connecting a direct-current power supply to the module, introducing reverse current which is 1.5-2.5 times of short-circuit current of the module in a constant-current mode so as to generate temperature required by testing, keeping the temperature for more than 10min, and recording a current value and a voltage value of the power supply; s3, switching the circuit to a constant-voltage mode, keeping the voltage value recorded in the step S2 for 10 minutes, and keeping the voltage value stable; s4, loading a front 2400PA dynamic mechanical load to the module, maintaining the front 2400PA dynamic mechanical load for not less than 24 hours, and continuously recording a power supply current value during the period; and S5, if the current value fluctuation in the period is less than or equal to 3%, determining that a high-temperature mechanical load test of the module is qualified, otherwise, determining that the module is unqualified. According to the invention, a mode of externally applying a high-temperature mechanical load is adopted, so that the new process module is subjected to mechanical deformation at high temperature to verify the long-term reliability of outdoor useof the module, and is very worthy of popularization.

Description

technical field [0001] The invention relates to the technical field of crystalline silicon photovoltaic modules for ground use, in particular to a reliability detection method for photovoltaic modules. Background technique [0002] With the development of photovoltaic module technology and the wider application of new products, new cell interconnection processes (such as shingling, splicing, etc.) are constantly emerging, and new cell interconnection materials (such as conductive glue, solder paste, flexible ribbon, etc.). [0003] These newly added materials play a vital role in the internal interconnection of components and current transmission. These materials also have some characteristics of their own, such as the low melting point of solder paste, and the reduced bonding performance of conductive adhesives at high temperatures. There are also some extreme conditions in the outdoor application conditions of photovoltaic modules, at which time these characteristics of t...

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Problems solved by technology

[0006] 2. Due to outdoor weather and other reasons, the components will bear certain mechanical deformation, especially in plain windy areas;

[0007] 3. At present, the conductivity and bonding performance of silicone and acrylic conductive adhesives that are widely used in the market will be reduced when they are exposed to high temperature (between 120°C and 140°C) for a long time (heated to 120°C, very Easy to disassemble shingled battery string)

[0008] 4. The melting point of low-temperature solder is about 130°C, and there is a lack of corresponding detection whether the molten solder can play an effective conductive interconnection role at the component end;

[0009] 5. Heterojunction batteries are mostly welded with low-temperature ribbons, and the welding tension is low. Whether this weak welding can ensure the long-term reliability of the components also requires corresponding detection methods

New process components are still tested according to the original reliable new detection method, which is not conducive to the guarantee of long-term reliability of components

[0012] (2) The detection of mechanical deformation is included in the international standard, such as the mechanical load test of IEC61215-10-16, but it is not carried out at high temperature. New processes such as conductive adhesive and solder paste have good conductive interconnection performance at room temperature Yes, so the test results are not convincing

[0013] (3) High temperature testing is included in international standards, such as the hot spot durability test of IEC61215-10-9, but there is no external force to deform the components in this test, and it is impossible to simulate outdoor use, while the thermal cycle of IEC61215-10-11 In the experiment, the highest temperature in the IEC61215-10-13 damp heat test is 85°C, which is not enough to reduce the adhesive force of the conductive adhesive, without external force deformation, and the test period is long

[0014] Therefore, the current existing reliability verification lacks a method that can detect the long-term reliability of components that undergo mechanical deformation at high temperatures

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