广域系统低频振荡多扰动的稳定域机理

由于系统扰动和操作的特性,广域系统中的低频振荡总是呈现出多重扰动现象,给传统的稳定性分析方法带来了一定的挑战。针对该现象提出了断面潮流分析模型,以该模型为基础给出了求取广域系统能量函数、稳定域的实用方法和利用该理论分析低频振荡多重扰动机理的流程。该方法能够进行广域大系统的实时在线安全评估和预警,若在此基础上施加相应的控制策略,可大大提升系统的能控能观性,从而能进一步保证系统的安全、可靠、经济和高效运行。可有效减少由于电网稳定性破坏导致的大面积停电事故,形成安全、可靠的现代电网。该方法尤其适用于省间、区域间电网在多重扰动后的稳定性分析。以四机两区域系统和华中电网作为算例,进行了大量的仿真分析。结果验证了所提方法的有效性和正确性。

Mechanism of Low Frequency Oscillation with Multiple Disturbances Based on Stability Region Theory in Wide-area System

Because of the characteristics of disturbances and operation in system,low frequency oscillation in wide area power system always performs multiple disturbances phenomenon, which brings huge challenge to analysis and control. Based on this phenomenon,a model named section power flow analysis is proposed. Based on this model,a practical approach is given to present for getting the energy function and stability region of wide-area power system. Then, a flowchart is presented on how to use stability region theory to analyze the low frequency oscillation with multiple disturbances. This method can be carried out in wide-area power system for on-line real-time security assessment and warning, on this basis some control strategies can be brought out correspondingly. So the controllability,observability of the system will be promoted at a higher level. As a result, a safe, reliable, economic and efficient power system will be secured well. And blackouts incidents caused by power system stability failure can be controlled. Meanwhile, it can improve system reliability. IEEE 4 machines 11 nodes system and Central China Grid system are used for simulation and analysis. At the same time, many results are obtained with different multiple disturbances. And the results verify the correctness and effectiveness of the proposed method. This method can be used for analyzing,monitoring,and emergency control for low-frequency oscillation with multiple disturbances in practical wide-area system with guiding significance.