电力系统低频振荡性质频域判别方法  

Frequency-Domain Method for Identifying the Property of Low Frequency Oscillations

作　　者：冯双[1] 蒋平[1] 吴熙[1] 李安娜[1] 

机构地区：[1]东南大学电气工程学院,江苏省南京市210096

出　　处：《中国电机工程学报》2016年第9期2357-2365,共9页Proceedings of the CSEE

基　　金：国家自然科学基金项目(51577032);"十二五"国家科技支撑计划重大项目(2011BAA01B02)~~

摘　　要：负阻尼低频振荡和强迫功率振荡是两种典型的低频振荡,它们的发生机理和抑制措施有本质的区别。因此,准确判断低频振荡性质对选择合理的抑制措施具有较大的参考价值。根据分析,两种低频振荡的频谱分布有显著差异,据此提出了一种频域判别法。首先采用复调制细化谱分析的方法对振荡数据进行精细化频谱分析,获得高分辨率和高精确度的频谱分布。在此基础上,采用反距离加权插值方法拟合频谱,对拟合值和原频谱进行比较,以判别是否存在间断点,从而辨识出低频振荡的类型。华东电网的实际系统算例验证了所提方法的有效性、抗噪性和鲁棒性。Low frequency oscillation （LFO） of negative damping mechanism and forced power oscillations are two typical kinds of LFO. The mechanism and suppression methods of them are different essentially. Therefore, identifying the property of LFO correctly is of great importance to the adoption of reasonable suppression methods. According to the theoretical analysis, there are significant differences between the spectral distributions of the two kinds of LFO. Thus, a frequency-domain method for identifying the property of LFO was proposed. Firstly, the zoom fast Fourier transform （Zoom-FFT） was adopted to analyze the oscillation data and obtain the spectral distribution with high resolution and accuracy. On this basis, the frequency spectrum was fitted with the inverse distance weighted （IDW） interpolation. The fitted values were compared with the values obtained with Zoom-FFT to recognize the discontinuity point and thus the property of LFO is identified. The simulation results in East China power grid demonstrate that the proposed method is effective and has good robustness and anti-noise capacity.

关 键 词：负阻尼低频振荡 强迫功率振荡 性质判别 复调 制细化谱分析 反距离加权插值 频域 

分 类 号：TM71[电气工程—电力系统及自动化]