SEDC与TCSC联合抑制次同步振荡的研究

Research on Sub-Synchronous Oscillation Mitigation Using Supplementary Excitation Damping Controller and Thyristor Controlled Series Capacitor

可控串联补偿(TCSC)工作在调节模式时,可以连续调节线路串补度,从而改变次同步振荡的条件;此外,TCSC所产生的谐波频带非常宽,足以使次同步频率的信号通过,在某些情况下可能激发次同步振荡。因此,当系统中包含TCSC时,次同步振荡问题的研究尤为复杂。本文提出使用附加励磁阻尼控制器(SEDC)与TCSC联合运行抑制次同步振荡,分析了TCSC不同运行状态对次同步振荡产生的影响,针对TCSC的运行特性,分段设计了两组SEDC参数,并模拟实现了SEDC参数间的切换。结果表明:通过切换控制参数,SEDC获得了更好的鲁棒性,TCSC的安全运行范围大大增加。

Operating in vernier mode thyristor-controlled series capacitor（TCSC） can control the degree of series compensation consistently,and changes sub-synchronous oscillation（SSO） conditions as a result.Besides,band width of the harmonic created by TCSC is wide enough to allow signals at subsynchronous oscillation frequency to pass.And this could excite SSO under certain conditions.Because of these reasons,study of subsynchronous oscillation problems on systems operating with TCSC is much more complicated.This paper focuses on using SEDC and TCSC operating in combination to suppress SSO.The impact of different TCSC operating conditions on SSO was studied.2 sets of SEDC parameters were given respectively based on the operating characteristics of TCSC.And switching between 2 sets of parameters was carried out by simulation.Our results show that by switching control parameters we can have a better robustness on SEDC and increase the safety operating range of TCSC greatly.