局部振荡引起区间大功率振荡的机理

从小干扰稳定性分析中的特征值分析方法出发，利用右特征向量的特征和发电机功角特性分析了局部振荡模式引起区间联络线上大功率振荡的机理。指出局部振荡模式的特征值随着运行工况的变化而变化，从而各机组该模式的右特征向量之间的关系也发生变化，当局部振荡模式所在联络线的那一侧的所有发电机的功率增量和出现较大数值时，则在该区间联络线上发生较大的功率振荡。以实际发生的功率振荡为具体实例，从小干扰稳定和时域稳定计算上证明了这种机理的存在，并提出了相应的分析方法及改善措施。

Tentative Study of Inter-area Large Power Oscillation Mechanism Caused by the Local Mode

Based on eigenvalues analysis of small signal stability analysis, mechanism of interconnected-lines' large power oscillations is studied by right eigenvector characteristic and generator power-angle characteristic. Eigenvalue of local mode changes with running condition and then relations between right eigenvectors of all generators also changes. If power increment sum of all generator units located in the one area occurred local mode oscillations would be serious, the large power oscillation in interconnected lines emerged. A four-generator power system and a field data case of West Inner Mongolia power grid oscillation proved the oscillation mechanism being, and corresponding analytic method and improved measures are proposed.