Aiming at problem of low sampling rate signal is susceptible to interference

count against realtime monitoring

while ultra high frequency（ UHF） sensor for partial discharge monitoring has problem of low communication speed

and can not realize fault recording of traditional partial discharge monitoring

a gas insulated switch-gear（ GIS） partial discharge monitoring system based on Ethernet is designed. The system consists of a master control acquisition system and several sensor module

0. 3

2 GHz UHF electromagnetic wave signal is obtained by sensor module and the frequency dropped to 2

10 MHz by

logarithmic detector;the signal collected by master acquisition system

cached by SDRAM and send to substation administrator by Ethernet. Test results show that the system has strong function

high speed

stable work

large scale monitoring

when the partial discharge occurs

the system can send alarm signal in real time and provide fault signal waveform for fault analysis. The actual speed of 10 /100 M Ethernet up to 500 k B / s

over 90 times than communication speed of traditional RS—485.