Photovoltaic module adjusting circuit and remote monitoring system

Abstract

The invention discloses a photovoltaic module adjusting circuit and remote monitoring system. Two adjacent photovoltaic modules connected in series are connected with an adjusting circuit. When one photovoltaic module is overshadowed or is under other non-normal conditions to result in inconsistent voltages of the adjacent photovoltaic modules, the adjusting circuit starts to work and adjusts the voltages of the adjacent photovoltaic modules to make the voltages consistent so as to realize terminal voltage balance and improve the overall output power of the module string. The adjusting circuit is provided with a digital signal processor, a communication module and a monitoring terminal. Voltage, current and temperature state of the photovoltaic modules can be monitored in real time, the state information of the photovoltaic modules can be collected, and any series-connected photovoltaic module which is overshadowed or is under other non-normal conditions can be automatically adjusted. The overall output power of the photovoltaic module string is improved. A controller is high in efficiency and low in loss. The adoption of a graphical monitoring terminal interface enables users to conveniently perform performance analysis and fault diagnosis on a photovoltaic system.

Description

technical field [0001] The invention relates to the technical field of solar photovoltaic power generation, in particular to an adjustment circuit and a remote monitoring system of a photovoltaic module. Background technique [0002] The voltage of the single solar cells is relatively low, and the single solar cells are generally connected in series to make the output voltage meet the load requirements. Photovoltaic modules are generally packaged by combining multiple single solar cells in series and parallel. Photovoltaic modules will produce a "hot spot effect" due to partial shading, that is, the short-circuit current of the shaded solar cells will become smaller, which will limit the output of the series circuit. current. In the module, part of the photogenerated current of the normal non-shading solar cell makes its own PN junction positively biased, forming a positive bias; in the circuit, the shading solar cell is subjected to reverse bias, and the shading solar cell...

AI Technical Summary

Problems solved by technology

However, although the bypass diodes in parallel avoid the aggravation of the "hot spot effect" and reduce the power loss of solar cells, they cannot completely save the overall string power loss caused by shading.

[0004] Photovoltaic modules are shaded or due to differences in manufacturing processes, which will lead to inconsistent photovoltaic cell parameters

In the photovoltaic module series system, the output power is no longer a single-peak curve, but multiple peaks, and the maximum power tracking algorithm used is difficult to find the actual maximum power point

Photovoltaic modules work under the above conditions, and some power will inevitably be lost

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