Measurement And Analysis Of Radiation Electric Field By Action Of GIS Circuit Breaker

With the development of electric power system,in the process of reform and construction of substation,GIS substation(Gas Insulated Substation)has gradually replaced the traditional open type substation AIS(Air Insulated Substation),but also brought some problems,and had received wide attention of the power workers.Because the GIS substation covers a small area,led to the secondary weak current equipment was forced to move away from the control room to the place where is not far from primary equipment,make the secondary weak current equipment is exposed to the serious electromagnetic interference environment.switchgear is one of the main interference sources of electromagnetic interference in substation,and it moves can produce radiation field that has certain influence on the insulation of the primary equipment and the normal operation of the two weak current equipment.Therefore,studying the rules of the radiation field produced by the switch operation in the substation is not only helpful to the safe run of the substation,but also can reduce the electromagnetic interference of the substation from the sources.In this paper,the radiated electric field generated by the action of GIS circuit breaker with different voltage levels was measured firstly,and the experimental data were analyzed,and then obtained the distribution of amplitude,frequency and duration of the radiation field characteristics,the main work is as follows:First,we developed a set of optical fiber measurement system,it can be used in the radiation field measurement under serious electromagnetic environment,and it's frequency bandwidth is 1000Hz?400MHz,and the measurement range is 800V/m?50kV/m,and has good characteristics of rising edge,can satisfy theradiation fieldmeasurement in the most of environment.second,with the help of uhv laboratory in XIHART to test the performance of GTS circuit breaker,to test the radiation electric field of 550kV,1100kVGIS circuit breaker has produced with the optical fiber measurement system,and obtained more than ten groups of experimental data in the end.Finally,with the help of the MATLAB platform to analysis of the 5 groups of experimental data(3 groups of 550kV experimental data,2 groups of 1100kV experimental data)in the time domain and frequency domainrespectively,and then the time-frequency analysis of the 5 groups of experimental data is carried out by using the short-time Fourier transform and wavelet transform.So we can get the distribution regularity and frequency range of the radiation electric field interference pulses.The results show that the 550kVGIS circuit breaker produces' radiation electric field pulse amplitude can up to 0.13kV/m and the frequency range from several MHz to tens of MHz,and 1100kVGIS circuit breaker produces' radiation electric field pulse amplitude can up to 0.78kV/m and the frequency range from tens MHz to hundreds of MHz.And the radiation electric field frequencyusually presented in the form of frequency band,and high frequency and low frequency separated clearly.The high frequency band is scattered,decay quickly,lasted for a short time,and low frequency band is concentrated,decay slowly,lasted for a long time.