Research On Key Technologies Of ±1100kV UHVDC AC&DC Harmonic And Resonance Characteristic

The development of UHVDC trasmission system is highly required in the 13 th Five-Year Plan of China.±1100k V UHVDC is the most advanced techinology of this area,and the ultra high voltage also brings out lots of issues needed to be researched.This paper mainly research on the key issue of ± 1100 k V UHVDC system harmonic characteristic,such as harmonic influence between splited AC system,resonance with 3000 km DC transmission line,and finally give out the AC&DC filter configuration of the Changji-Guquan±1100k V UHVDC project.This paper is based on areal system conditionof Changji-Guquan±1100k V UHVDC project,which is in build.First,each poleof the systemcontains two series of 12 pulse converter respectivelyconnected to two independent 500 k V/1000 k V AC system.Whetherthe harmonics generated by converter will be effected bythemutual impedance betweenspilit AC system has beengiven out in thispart of research.Then the simulation calculation gives out the actual AC filter configuration with AC side harmonic performance results at the inverter station.This paper study also research on the low order resonance characteristics of over 3000 km DC transmission lines,using lumped parameter equivalent model method,it is concluded that the resonant impedance characteristics of the DC system,and on this basis,accordingtothe ± 1100 k V project specialty,give out a technical-economy comparetion of converter stations filter configuration and performance on DC side,finally recommanded the optimization of DC filter configuration.