Research On Harmonic Characteristic Of Ultra High Voltage AC Transmission System

China 1000kV AC Pilot Project from Jindongnan to Jingmen via Nanyang has been put into operation in January 2009, but there still exist many problems to be explored or researched for the independent innovation project, harmonic analysis on UHV AC Transmission System is one of them, which need to research deeply.Based on the electromagnetic relations and the effect of iron core nonlinearity of shunt reactor and autotransfomrer, a new model of them used for harmonic analysis and computer simulation is presented.Against the background of 1000kV AC Pilot Project from Jindongnan to Jingmen via Nanyang, based on accurate modeling of the nonlinear equipments such as autotransformer and shunt reactor in 1000kV system, the harmonic characteristics of 1000kV system are calculated and analyzed in PSCAD/EMTDC. Finally, measures and suggestions are proposed to reduce the harmonic level of UHV system.