摘要
电力系统多摆失稳的根本原因在于主导映像系统的非哈密顿特性 ,经典模型下起主要作用的是互补簇簇内的不同调性 ,它综合反映在不平衡功率—位置量曲线的非周期程度上。对于提前终止数值积分 ,即根据短时段内的稳定轨迹来估计系统的后续稳定性的问题 ,分析了难以用轨迹的频域特性作为判据的原因 ,并提出了预估的方法。基于扩展等面积准则 (EEAC) ,选取相邻摆次动能的最大变化量、动能的平均变化率以及映像系统功角曲线与理想哈密顿系统功角曲线所围面积作为定量指标 ,以反映互补簇内的不同调程度 ,并参考各摆的最小稳定裕度 ,得出判别系统暂态稳定性的 3条判据。然后综合由不同判据得出的结论 ,将算例划分为后续稳定、后续不稳定及尚不能确定 3类子集 ,对前两类算例可提前终止积分 ,属于尚不能确定的算例则需继续积分。对不同系统、不同故障及不同模型下算例的仿真计算表明了这一方法的可靠性。
The multi-swing instability of power system is mainly due to incoherency in the complementary clusters of the controlling image system. It is reflected in the non-sinusoidal of unbalanced force-position curve. The reason why the spectrum of this curve can't be used to justify the stability after the integration window is discussed. A method is proposed to predict long-term stability with short-duration numerical simulation. Based on EEAC (extended equal-area criterion) three indices are proposed to indicate the incoherency of the system. Correspondingly, three criterions and their thresholds are suggested for predicting the stability after the simulation period. The rules for coordinating their results are investigated. The cases are classified into three subsets. For the long-term stable cases and unstable cases, the simulations can be terminated as early as possible to save computational burdens; for other cases, simulations should be continued. Applications to different systems and different faults demonstrate the security and validity of the proposed approach.
出处
《电力系统自动化》
EI
CSCD
北大核心
2002年第3期1-5,共5页
Automation of Electric Power Systems
基金
国家重点基础研究专项经费 (G19980 2 0 30 1)
国家自然科学基金 (5 992 0 0 37)
