阻抗不均导致振荡中心迁移的规律  

The Mechanism of Oscillation Center Migration Due to Impedance Inequality

作　　者：刘福锁[1] 方勇杰[1] 李威[1] 薛峰[1] 袁虎玲[1] 

机构地区：[1]南京南瑞集团公司(国网电力科学研究院),江苏省南京市210003

出　　处：《电网技术》2014年第1期193-198,共6页Power System Technology

基　　金：国家电网公司重大专项资助项目(S G C C-MPLG003-031-2012)~~

摘　　要：基于计及阻抗不均的等值两机系统模型,采用向量图和数值计算相结合方法研究了线路阻抗不均导致振荡中心偏移的规律。定义两机系统总阻抗模值的中点为系统中心。在系统功角由0?360?摆周期中,系统阻抗角不等可导致振荡中心动态迁移:当系统中心落在联络线上时,振荡中心仅在联络线内部动态迁移。当系统中心落在联络线任侧系统等值阻抗上时,存在两种迁移规律,是仅在联络上动态迁移,二是振荡中心在联络线和系统中心所在的联络线侧等值阻抗上动态迁移。系统失步中心位置(振荡周期内电压过零点)不受阻抗不均的影响,不影响失步中心位置的定位,但失步中心并非只在系统功角摆至180?时出现。The regulation and mechanism of oscillation center migration are studied by integrating vector graph and numerical calculation method, based on a two-machine equivalent system model considering impedance inequality. The midpoint of total impedance absolute is defined as the system center. Research results show that impedance inequality will cause migration of oscillation center during an oscillation cycle in the power system angle from 0° to 360° swing cycle. Oscillation center just migrates only inside contact lines when the system center is located at the contact lines. When the system center is located at equivalent system impedance at either end of contact lines, there are two kinds of migration, one is only inside contact lines, the other is the oscillation center may migrate in lines, but more likely migrationes between the lines and the equivalent system impedance that the system center is located. The position of out-of-step center is not affected by the impedance inequality, but out-of-step center occurs not only when the system angle is 180°.

关 键 词：振荡中心 动态迁移 失步振荡 阻抗不均 

分 类 号：TM721[电气工程—电力系统及自动化]