A test device for a photovoltaic junction box

Abstract

The invention discloses a test device for a photovoltaic junction box, which is applied to a photovoltaic junction box with a sub-string MOS tube connected between a first PV terminal and a second PV terminal, including a first test module and a second test module; The first end of a test module is connected to the first PV end of the junction box to be tested, the second end of the first test module is connected to the second PV end of the junction box to be tested, and the difference between the first PV end and the second PV end is changed. The voltage between them simulates the failure of the battery substring, and the bypass function of the junction box to be tested can be detected by detecting whether the MOS tube of the substring is turned on; the first terminal of the second test module is connected to the OUT+ terminal of the junction box to be tested , the second terminal of the second test module is connected to the OUT-terminal of the junction box to be tested, and the voltage between the OUT+ terminal and the OUT-terminal is changed to simulate the situation that the junction box to be tested needs to be turned off. By detecting whether the main MOS tube is turned on The shutdown function of the main MOS transistor of the junction box to be tested can be detected.

Description

technical field [0001] The invention relates to the technical field of component testing, in particular to a testing device for a photovoltaic junction box. Background technique [0002] Photovoltaic junction box is a connection device between the solar cell square array composed of solar cell components and the solar charging control device. Its main function is to connect and protect solar photovoltaic components, connect the power generated by solar cells with external lines, and conduct photovoltaic current generated by the component. [0003] Traditional photovoltaic junction boxes usually use bypass diodes, which are turned on when the current of a certain battery substring is small, and the battery substring is bypassed to avoid hot spots. However, due to the diversity of solar panel installation locations, the solar panel may be shaded during operation, which will induce the activation of the bypass protection element (usually a diode) in the junction box behind the...

AI Technical Summary

Problems solved by technology

However, due to the diversity of solar panel installation locations, the solar panel may be shaded during operation, which will induce the activation of the bypass protection element (usually a diode) in the junction box behind the panel, and the battery string A DC current of up to about 9A will be instantly loaded on the bypass device, causing a high temperature of more than 100 degrees in the junction box. This high temperature will have little effect on the battery board and junction box in the short term, but if the shadow effect is not eliminated If it exists for a long time, it will seriously affect the service life of the junction box and the battery board

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