Calculation And Analysis Of Operation And Lightning Overvoltage In 1100kV GIS

In recent years,China has vigorously promoted the construction of UHV transmission projects,and has successfully built and operated a number of UHV AC and DC transmission projects.With the development of UHV transmission technology,gas insulated substation(GIS)has been widely used,but the overvoltage in GIS substation of GIS insulation and safe and reliable operation of the system level has an important influence.Therefore,it is very important to study the operation overvoltage and lightning overvoltage of GIS substation.In this paper,the calculation and analysis of the ultra fast transient overvoltage(VFTO)and lightning surge overvoltage in a 1100kV GIS substation are carried out.First,analyzes the selection method of calculation method and parameters of the main components of equipment in GIS model,ATP-EMTP VFTO established the 1100kV equivalent of GIS substation simulation calculation model based on the research of transformer substation in isolating switch operation generated,including amplitude and frequency characteristics,and then analyzes several typical the inhibition of VFTO measures.Finally,according to the lightning wave parameters,a GIS substation lightning over-voltage equivalent simulation model,using double exponential wave and oblique flat wave two lightning current waveform simulation,characteristic wave overvoltage of transformer substation lightning invasion were studied,analyzed the influence of MOA on lightning arrester protection performance of voltage.The simulation results show that the various electrical equipment to determine the variation of degree of node VFTO in different operation modes under different switch produced in isolation;closing operation case of the VFTO amplitude below the switch operation of the VFTO amplitude,in the case of brake frequency oscillation components higher;distance switch operation point the closer,the amplitude and frequency of VFTO determination of the corresponding node is also larger;arrester(MOA),closing resistor,ferrite bead on the inhibition of VFTO to a certain extent,but these measures have their own advantages and disadvantages;the equivalent oblique wave simulation of lightning current the maximum voltage value ratio double exponential wave simulated value is bigger,but considering the factors of transmission line and tower,the maximum voltage value is close to MOA;lightning arrester for Lightning Electric GIS on each device The pressure has better protection performance.