±800 kV特高压直流输电工程换流器投退策略分析

Strategy of Converter Entry/Exit for ±800 kV UHVDC Project

特高压直流输电工程采用双12脉动阀组串联的接线方式,存在多种运行方式,因此需研究单换流器在线投/退策略。以向上士800kV特高压直流输电工程为参照对象,讨论了双12脉动阀组的运行方式和电压平衡,详细阐述了极运行时整流侧和逆变侧换流器的投退过程及其投退时触发角控制。借助EMTDC仿真,验证了单一换流器投退顺序控制的动态过程。结果表明该控制策略方案完全满足特高压直流系统设计的要求,对后续的特高压直流输电工程具有直接的指导意义。

The series connection of dual 12-pulse valve groups adopted in the HVDC transmission project operates in multiple modes;therefore,it is necessary to study strategies of converter online entry/exit.Using Xiangjiaba-Shanghai±800kV HVDC transmission project as referent,this paper discusses the operation mode and voltage balance of dual 12-pulse valve groups,and elaborates entry/exit process and the firing angle control of converter for two stations in the pole running.EMTDC simulation was applied to verify the dynamic process of sequential control for entry/exit of single converter group.Simulation results show that the proposed control strategy can completely satisfy the design requirement of HVDC power transmission system,which can provide direct guidance for the follow-up UHVDC transmission projects.