摘要
在远距离内输电线路中串入固定电容器,可能会引起次同步谐振(SSR),为此,在串补系统中使用了基于电压源换流器(VSC)的新一代串联补偿装置静止同步串联补偿器(SSSC)来替代部分固定电容器。首先分析了SSSC基本运行原理,通过对VSC输出电压幅值和相位的控制,使SSSC能够向线路中注入串联的容性电压,相当于提供了串联补偿电容。分析了不同容量SSSC的电气阻尼特性,针对SSSC原有控制抑制次同步谐振效果不佳的缺点,设计了SSSC次同步谐振多模式阻尼控制器。通过通带内低相移的扭振模式带通滤波器滤出系统每个扭振模式信号后再进行相位补偿,使SSSC能够在所有扭振频率附近提供正的电气阻尼。基于测试系统的频域和时域仿真结果表明,简单地增加SSSC的容量并不能有效地化解系统发生次同步谐振的风险,所设计的多模式阻尼控制器不仅能够阻止发电机和串补线路之间次同步谐振的产生,并且能有效地减小所需SSSC装置的容量。
To mitigate subsynchronous resonance problem caused by series capacitor,the application of a VSC based static synchronous series compensator（SSSC） in series compensated system is investigated.The modeling and basic operation principles of SSSC were analyzed.By controlling the angular position and magnitude of the VSC output voltage,the SSSC can inject ac compensating voltage in series with the line.A case study based on modified IEEE first benchmark model（FBM） was adopted to investigate the SSSC damping characteristics with varied SSSC rating.A multimode damping controller was then developed to suppress multiple unstable torsional frequencies.Special band-pass filters having low passband phase shift were used to obtain signals of multiple torsional modes.By phase compensation of each mode,the SSSC damping controller could provide positive electrical damping around each torsional frequency.Simulation results based on modified IEEE FBM show the proposed controller can not only mitigate subsynchronous resonance effectively,but also reduce the power rating of the SSSC,leading to a cost-effective solution for SSR suppression.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2011年第9期2321-2327,共7页
High Voltage Engineering
基金
国家高技术研究发展计划(863计划)(编号略)~~
关键词
静止同步串联补偿器
次同步谐振
测试信号法
电气阻尼
多模式阻尼控制器
低相移带通滤波器
static synchronous series compensator（SSSC）
subsynchronous resonance（SSR）
test signal method
electrical damping
multimode damping controller
low passband phase shift filter
