Intelligent protection device and method for surge protector

Abstract

The invention relates to intelligent protection device and method for surge protector. The device comprises a power frequency leak current signal sampling module, a power frequency voltage signal sampling module, a control unit, a switch drive module, a switch module, and a power module. The power frequency leak current signal sampling is provided with an input end to be connected with the surge protector and an output end connected with the control unit. The power frequency voltage signal sampling module is provided with an input end to be connected with a power grid and an output end connected with the control unit. The control unit processes the input data to obtain processing results and outputs switch control signals according to the processing results. An input end of the switch drive module is connected with the control unit, and the switch drive module receives switch control signals output by the control unit. The switch module is opened or closed by driving of the switch drive module, an input end of the switch nodule is used to be connected with the power grid, and an output end of the switch module is used to be connected with the surge protector. The power module is used for connecting the former modules. The intelligent protection device and method are applicable to intelligent management and protection of the surge protector.

Description

technical field [0001] The invention relates to the field of surge protection, and more specifically, to an intelligent protection device for a surge protector and an intelligent protection method for a surge protector. Background technique [0002] Surge protector SPD is an indispensable device for lightning protection of electronic equipment. The current leaks to the ground to protect the protected equipment or system from impact. The main core component of SPD is metal oxide varistor (hereinafter referred to as MOV), but it will age and fail with the increase of service time. Under power frequency overvoltage, MOV is easy to break down and fail, and it will be short-circuited after failure. When the power frequency short-circuit accident current passes through MOV, it will cause fire. In order to protect it from fire, over-current protection technology and thermal protection technology are usually used now: [0003] The principle of overcurrent protection technology is ...

AI Technical Summary

Problems solved by technology

However, the larger the selected overcurrent protection device or device specification, the higher the short-circuit current that requires fast action. In many cases, the short-circuit current in the power grid cannot be large enough to quickly disconnect these over-current protection devices, making the over-current protection The device cannot be disconnected before the SPD catches fire, so it cannot protect the SPD; and the selected over-current protection device is too small to ensure rapid disconnection when the fault current is short-circuited, but these over-current protection devices are in a large lightning strike When the current occurs, it is easy to be damaged or malfunction, thus losing the protective effect on the protected equipment

[0007] For the thermal detachment protection technology, if the power frequency fault overvoltage is too high, the MOV in the SPD will be broken down and damaged in a short time. If the thermal detachment device cannot operate before the MOV breaks down and short circuit, the heat generated by the components will decrease after the breakdown , the temperature rises very slowly or does not rise to the action temperature of the thermal disconnector, then the SPD may catch fire and burn, and the greater the short-circuit current flows after the SPD element fails, the faster the SPD will catch fire

[0008] Therefore, whether it is the existing overcurrent protection technology or the thermal separation protection technology, it still cannot completely solve the problem of SPD failure and fire. In some cases, the SPD will still catch fire.

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