暂态稳定视角下的强关联输电断面及其识别方法

Strong Correlated Transmission Sections and Their Identification Method from Perspective of Transient Stability

多个交流输电断面暂态稳定极限功率相互耦合,给电网安全稳定运行控制带来了极大挑战。文中深入挖掘受扰系统中暂态响应轨迹特征与稳定模式的对应关系,提出了暂态稳定视角下关键输电断面及关联断面的概念,并将关联输电断面分为模式共存机理决定的关联断面和模式演化机理决定的关联断面两类。提出了基于电网电气量变化来反映系统稳定模式的支路同步力系数指标,并结合该指标、图论和暂态稳定模式识别方法,提出了关键断面及关联断面识别的实用算法,有利于克服人工经验方法中因机理分析不足而可能导致的识别不准和效率低下的缺陷,为基于输电断面准确识别的稳定分析或运行监控提供了基础。基于IEEE 10机39节点系统的算例阐明了所提方法的原理及有效性。

The coupling of transient stability limit power among multiple AC transmission sections brings great challenges to the security and stability operation of the power grid. Based on digging the corresponding relationship between the transient response trajectory characteristics and the stability mode in the disturbed system, the concept of the key transmission section and the associated sections from the transient stability perspective is proposed. The associated transmission sections are classified as the mode-coexistence mechanism determined and mode-evolution mechanism determined sections. The index of the synchronization force coefficient is put forward for the disturbance severity of the branch, which is used to reflect the system stability model based on the electrical quantity changes. A practical algorithm for identifying the key section and related sections is then put forward by combining the index, the graph theory and the transient stability mode identification method. The proposed algorithm is helpful for overcoming the lack of inaccuracy and inefficiency of the artificial experience method which is lack of mechanism analysis guidance. It provides the basis for the stability analysis or operation monitoring of the power grid security and stability coordination control based on the accurate identification of transmission section. Based on the example of IEEE 10-machine 39-node system, the principle and effectiveness of the proposed method are illustrated.