Photovoltaic inverter and photovoltaic system

Abstract

The invention discloses a photovoltaic inverter which comprises a flyback converter, an inverter circuit, an alternating voltage detection module and a control module. Specifically, the flyback converter firstly boosts the first direct current output by a photovoltaic module, so that the inverter circuit can invert the boosted second direct current and input the second direct current into an alternating current power grid. The flyback converter realizes multiplexing of the primary side main switch tube and the short circuit switch in the flyback converter, and when the AC voltage detection module detects that the AC power grid is disconnected, the control module sends a safety regulation closing instruction to control the short circuit switch to be closed so as to turn off the output voltage of each photovoltaic module, thereby meeting the requirements of safety regulations, and being simple in structure and low in cost. The invention further discloses a photovoltaic system which has the same beneficial effects as the photovoltaic inverter.

Description

technical field [0001] The invention relates to the field of electric energy conversion, in particular to a photovoltaic inverter and a photovoltaic system. Background technique [0002] Photovoltaic inverters can convert the direct current generated by photovoltaic modules into alternating current of mains frequency and output it to the alternating current grid. When the AC grid is disconnected, the photovoltaic inverter stops working, but the photovoltaic modules will output high voltage, which poses a safety risk and does not meet the requirements of safety regulations. Therefore, the safest way is to turn off the output voltage of photovoltaic modules to minimize the DC high voltage. In the prior art, an additional shut-off device is added at the output end of the photovoltaic module to shut off the output voltage of the photovoltaic module. Although this method can reduce the output voltage of the photovoltaic module, it also increases the power consumption of the phot...

AI Technical Summary

Problems solved by technology

In the prior art, an additional shut-off device is added at the output end of the photovoltaic module to shut off the output voltage of the photovoltaic module. Although this method can reduce the output voltage of the photovoltaic module, it also increases the power consumption of the photovoltaic inverter. The complexity of the structure also increases the cost

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