Signal protection filter circuit for electronic mutual inductor

Abstract

The invention discloses a signal protection filter circuit for an electronic mutual inductor. The signal protection filter circuit includes two signal input ends and two signal output ends. The two signal input ends and the two output signal output ends are connected to a protection circuit and a filter circuit therebetween. The protection circuit includes any one or any three combination of a gas discharge tube module, a pressure-sensitive resistance module and a transient inhibition diode module. The gas discharge tube module, the pressure-sensitive resistance module and the transient inhibition diode module are in coupled connection therebetween through a resistor or an inductor. The signal protection filter circuit inhibits overvoltage, overcurrent, common mode interference and differential mode interference. The signal protection filter circuit has simple structure, strong protection, excellent frequency response features and small influence on the precision of the electronic mutual inductor.

Description

technical field [0001] The invention relates to the field of electric power technology, in particular to a signal protection filter circuit for an electronic transformer. Background technique [0002] As an important part of the digital substation, the electronic transformer is the guarantee for the safe and stable operation of the power system. Since the electronic transformer is installed near high-voltage primary equipment, and its acquisition device uses a large number of electronic components, it is particularly susceptible to interference from harsh electromagnetic environments, resulting in abnormal output or damage to the electronic transformer. One of the interference sources of the electronic transformer is the signal port, so the signal port of the electronic transformer must be protected and filtered. [0003] In a common signal acquisition system, because the electromagnetic environment of the device is relatively safe and reliable, the signal circuit often add...

AI Technical Summary

Problems solved by technology

[0003] In a common signal acquisition system, because the electromagnetic environment of the device is relatively safe and reliable, the signal circuit often adds a transient suppression diode at the entrance to meet the design requirements, but its protection level is relatively weak, which cannot meet the requirements of electronic mutual inductance. device applications

Among the existing protective filtering technologies, lightning protection technology and EMC filtering technology are relatively mature. Although they have strong protection capabilities, they are usually used in applications such as lightning arrester design and power filtering, and there is no signal protection for electronic transformers. Special research, so the protective measures do not consider the influence of the circuit on the accuracy, resulting in problems such as the accuracy of the electronic transformer is out of tolerance, and the frequency response characteristics are not good.

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