【摘要】 电力系统暂态功角失稳模式同相关不稳定平衡点密切相关。鉴于电力系统失去暂态功角稳定时总是伴随着电力网络的某个或某些临界割集上支路角度急剧地、过大地增长,人们已经认识到电力网络中存在临界割集与系统模型中存在不稳定平衡点是等价的,并提出了用于电力系统暂态功角稳定分析的割集稳定准则。为了使人们能够放心地、正确地运用与临界割集相关的稳定准则,本文以电力系统结构保留模型为基础,从理论上推导出暂态功角稳定不稳定平衡点为i型的当且仅当事故后电力扩展网络中存在i个临界割集。利用上述结论,可以很容易地将割集稳定准则应用于多群失稳的情况,以消除原准则的保守性。更多还原

【Abstract】 A transient angle unstable mode of power system closely relates to a controlling unstable equilibrium point (UEP). Angles of branches in critical cutsets change rapidly and largely when the power system loses transient angle stability. People have realized that there exists a certain relation between the critical cutsets and the UEP for structure- preserving power system models and suggested the cutset stability criterion for transient angle stability analysis. For the proper use of the criterion, the relationship between the number of critical cutsets and the type of UEP with respect to transient angle stability is developed based on two structure-preserving power system models. The conclusion that the UEP is type-i iff there exist i critical cutsets in the post-fault network can be easily used to propose a modified cutset stability criterion, which will have less conservation than the original one, for the case of that the post-fault power system exists more than one critical group of generators.更多还原