异步联网后云南电网失步特性与解列系统方案研究

Research on Oscillation Characteristics and Out-of-step Separation System Scheme for Yunnan Power Grid After Asynchronous Interconnection

云南电网与南方电网主网实现异步联网,云南电网的失步振荡特性随之发生新的变化。利用基于电压比相原理和Ucosφ原理的失步振荡中心搜索方法,对异步联网后云南电网典型方式下的多重严重故障进行仿真研究,确定失步振荡中心的分布区域和失步断面的构成类型。云南电网目前配置的分散独立式失步解列装置,对于复杂断面的失步判别和解列效果均不理想,因此在研究云南电网失步特性的基础上,针对并列式失步断面和长链式失步断面,提出基于Ucosφ判据和电压比相判据的失步解列系统构建方法,设计并初步验证了滇西北、滇中西南、滇东北失步解列系统构建方案与初步策略。

Yunnan Power Grid and China Southern Power Grid have became an asynchronous network. There is a new change in the out-of-step oscillation characteristics of the grid. In this paper, four kinds of nmhiple serious faults are studied which are under the typical mode of Yunnan Power Grid. The out-of-step oscillation sections can be divided into two types, one is the parallel section and another is the long chain section. Yunnan Power Grid is currently equipped with distributed out-ot^step devices, which is not ideal for the out-of-step determination and separation for these two types of out-of-step sections. A method is presented to design an out-of-step system based on the Ucosq~ criterion and the voltage phase difference criterion. Three out- of-step systems are designed respectively for northwestern Yunnan, northeastern Yunnan and southwestern Yunnan. The strategies of the out-of-step systems are also developed.