Photovoltaic module quick turn-off protection device with low cost and high reliability

Abstract

The invention relates to a photovoltaic module quick turn-off protection device with low cost and high reliability. The photovoltaic module quick turn-off protection device is powered up by a power grid, is arranged between a photovoltaic module and an inverter and is connected between the photovoltaic module and the inverter by virtue of an IGBT and a normally closed alternating current relay, wherein IO is a normally closed alternating current relay driving signal, G1 is an IGBT driving signal, a time sequence control circuit respectively gives the IGBT driving signal G1 or the normally closed alternating current relay driving signal IO; when input of the power grid is present, the time sequence control circuit guarantees that a normally closed alternating current relay is turned on before an IGBT; and when the power grid is turned off, the normally closed alternating current relay is turned off after the IGBT, so as to guarantee that the normally closed alternating current relay isturned on and off under the condition that no direct current exists. The photovoltaic module quick turn-off protection device provided by the invention solves the arc discharge problem of the alternating current relay, and cost is greatly reduced; the device is small in volume and can be conveniently mounted below the module, and the requirement of being 3m away from the module is met; and turn-off protection is fast, safe and reliable, and personnel do not need to go to a roof.

Description

technical field [0001] The invention relates to a photovoltaic module rapid shutdown protection device, in particular to a low-cost and high-reliability photovoltaic module rapid shutdown protection device. Background technique [0002] Photovoltaic modules are connected to the grid through inverters. When a fire breaks out in a building or other accidents occur, emergency personnel should disconnect the modules immediately. However, since most of the modules are installed on the roof, it is difficult to ensure that the modules are disconnected. Timeliness and safety, so the photovoltaic module rapid shutdown protection device was produced under this background. [0003] At present, the existing fast protection devices for photovoltaic modules mainly use a combination of DC contactor or DC relay and an AC power switch, that is, the DC contactor is controlled by the grid power supply to turn on / off the module and the inverter. [0004] The above method can achieve the purpos...

AI Technical Summary

Problems solved by technology

[0004] The above method can achieve the purpose of quickly shutting down the components, but there are two problems: one is the installation problem, the volume is relatively large, and it is divided into two parts, which makes installation difficult; the other is the high price and cost of the DC contactor / relay

[0005] The AC relay is relatively cheap, but the AC relay will have arcing phenomenon when switching in the DC state

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