电力系统振荡中心的特性与识别

发布时间：2018-05-24 07:29

本文选题：振荡中心 + 振荡中心的识别　；参考：《华北电力大学》2014年硕士论文

【摘要】：我国能源资源分布与经济建设不平衡的基本情况决定了我国电力流西电东送的总体特征。因此,建设坚强可靠的电网已成为解决我国当前能源与经济发展问题的有效途径。然而,由于电网电气联系变得日益紧密,系统中一旦出现扰动,如果防控不及时、手段不奏效,雪崩式的多重严重故障就可能发生,进而诱发大停电事故。所以,能够尽早预测振荡中心位置,确定失步断面,并采取有效控制措施,这对于电网稳定安全可靠的运行具有极大意义。本文首先利用幅值相等的两机系统模型推导了失步过程中各电气量的数学表达式并总结了相应的变化规律。针对已有快速定位振荡中心算法的不足,提出其改进算法,该改进算法不受网络的运行方式以及网络结构变化的影响,提高了振荡中心定位的准确性。本文研究了失步过程中振荡中心的漂移特性及其影响因素,指出负荷模型和负荷大小对振荡中心漂移的存在重要影响,明确了振荡中心漂移的根本原因是输电线路两端电压幅值不等。分析了振荡中心电压Ucos φ推导的前提条件,并且根据系统的实际运行情况,提出了能够弥补已有算法不足的改进措施。本文将振荡中心快速定位的方法与振荡中心电压Ucos φ二者结合提出了一种带有预测功能的电力系统失解列判据,通过IEEE11节点经典算例验证了该方法可行有效,并把该算法应用到PSD-BPA软件中,实现了在华北-华中实际电网数据中仿真的应用,从而证明了该判据在系统进入失步运行前就可以准确预测到失步后振荡中心的位置,对于及时采取有效措施提供了重要的参考依据。
[Abstract]:The unbalanced distribution of energy resources and economic construction determines the general characteristics of electric power flow from west to east in China. Therefore, the construction of a strong and reliable power grid has become an effective way to solve the current energy and economic development problems in China. However, because the electrical connection of the power network becomes more and more close, once disturbance occurs in the system, if the prevention and control is not timely and the means are not effective, the avalanche type of multiple serious faults may occur, and then the blackout will be induced. Therefore, it is of great significance to predict the location of the oscillation center, determine the out-of-step section and take effective control measures, which is of great significance for the stable, safe and reliable operation of the power network. In this paper, the mathematical expressions of the electrical quantities in the out-of-step process are derived by using the two-machine system model with equal amplitude, and the corresponding variation laws are summarized. In view of the shortcomings of the existing fast positioning oscillation center algorithm, the improved algorithm is proposed. The improved algorithm is independent of the network operation mode and the network structure changes, and improves the accuracy of the oscillation center location. In this paper, the characteristics of oscillation center drift and its influencing factors are studied. It is pointed out that load model and load size have important influence on oscillation center drift. It is clear that the fundamental reason of the oscillation center drift is that the voltage amplitude at both ends of the transmission line is not equal. The precondition for derivation of oscillation center voltage Ucos 蠁 is analyzed. According to the actual operation of the system, the improvement measures are put forward to make up for the deficiency of existing algorithms. In this paper, by combining the method of quick location of oscillation center with Ucos 蠁 of oscillation center voltage, a criterion of power system failure with prediction function is proposed. The feasibility and effectiveness of this method are verified by a classical example of IEEE11 node. The algorithm is applied to PSD-BPA software to realize the application of simulation in the actual power network data from North China to Central China. It is proved that the criterion can accurately predict the position of the oscillation center after the system goes out of step before the system goes out of step. It provides an important reference basis for taking effective measures in time.
【学位授予单位】：华北电力大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM712

【参考文献】