One of the fundamental issues in gas insulated substations （GIS） which has destructive effects on GIS equipment is the very fast transient over-voltages （VFTOs）. This paper models a 400/230 kV substation in order ...One of the fundamental issues in gas insulated substations （GIS） which has destructive effects on GIS equipment is the very fast transient over-voltages （VFTOs）. This paper models a 400/230 kV substation in order to study the effects of VFTO extensively implemen- ted on EMTP-RV. In addition, the application of ferrite rings for suppressing VFTOs is assessed thoroughly. The main advantage of this paper is its new proposed algorithm according to the ferrite ring frequency dependent modeling that is validated with experimental results. This paper examines the effects of three compositions of the ferrite ring on VFTO suppression. Moreover, it estimates the dimension of the ferrite ring based on the SF6 gas insulation withstand and the maximum effect of ferrite rings on VFTO suppression constraint with the COMSOL multiphysics software. Furthermore, it gains VFTO attenuated percentages due to the installation of the ferrite ring in different GIS nodes. Finally, it analyzes the offered VFTO amendment technique in various GIS switching scenarios.展开更多
The resonant frequency of the ferrite-loaded cavities used in the future China Spallation Neutron Source (CSNS)sweeps from 1.02MHz to 2.42MHz.The ferrite property is very important to the accelerator structure in the ...The resonant frequency of the ferrite-loaded cavities used in the future China Spallation Neutron Source (CSNS)sweeps from 1.02MHz to 2.42MHz.The ferrite property is very important to the accelerator structure in the CSNS ring.A primary experiment was set up to measure theμrQf value and the power density of different ferrite materials.According to the comparison results,4M2 ferrite rings were chosen to meet the requirement of CSNS.展开更多
文摘One of the fundamental issues in gas insulated substations （GIS） which has destructive effects on GIS equipment is the very fast transient over-voltages （VFTOs）. This paper models a 400/230 kV substation in order to study the effects of VFTO extensively implemen- ted on EMTP-RV. In addition, the application of ferrite rings for suppressing VFTOs is assessed thoroughly. The main advantage of this paper is its new proposed algorithm according to the ferrite ring frequency dependent modeling that is validated with experimental results. This paper examines the effects of three compositions of the ferrite ring on VFTO suppression. Moreover, it estimates the dimension of the ferrite ring based on the SF6 gas insulation withstand and the maximum effect of ferrite rings on VFTO suppression constraint with the COMSOL multiphysics software. Furthermore, it gains VFTO attenuated percentages due to the installation of the ferrite ring in different GIS nodes. Finally, it analyzes the offered VFTO amendment technique in various GIS switching scenarios.
文摘The resonant frequency of the ferrite-loaded cavities used in the future China Spallation Neutron Source (CSNS)sweeps from 1.02MHz to 2.42MHz.The ferrite property is very important to the accelerator structure in the CSNS ring.A primary experiment was set up to measure theμrQf value and the power density of different ferrite materials.According to the comparison results,4M2 ferrite rings were chosen to meet the requirement of CSNS.
