摘要
电网中常见的低频振荡包括负阻尼低频振荡和强迫功率振荡,精确有效的低频振荡检测与类型判别对保障电网安全稳定运行十分重要。提出基于四阶混合平均累积量（fourthorder mixed mean cumulant,FOMMC）对角切片的低频振荡检测与类型判别方法。首先推导两种低频振荡的FOMMC对角切片数学表达式,并据此定义振荡检测指标,以检测低频振荡的发生。然后从高阶统计特征的角度深入对比分析两种低频振荡的FOMMC对角切片,并提出根据FOMMC对角切片的峰度判别低频振荡类型的方法。由于利用了低频振荡FOMMC对角切片与原振荡信号包含振荡模态的一致性和对高斯信号的自然盲性,上述方法不受随机功率波动或量测噪声造成的高斯色噪声的影响,即使在信噪比很低的情况下,仍然能够准确检测低频振荡并正确判别振荡类型。华东电网中的仿真结果验证了所提方法的有效性、准确性和抗噪性。
Main types of low frequency oscillations in power grid are those of negative damping mechanism and forced oscillations. Accurate and effective detection and diagnostic of low frequency oscillations is of great importance for safe and stable operation of power grid. This paper proposes a detection and diagnostic method of low frequency oscillations based on diagonal slice of fourth order mixed mean cumulant（FOMMC）. Firstly, mathematical expressions of these two low frequency oscillations are deduced and the criteria for detecting oscillations are defined. Then, the FOMMC diagonal slice of these two low frequency oscillations are analyzed and compared from aspect of high order statistics so that the diagnostic method of oscillation type according to kurtosis of FOMMC diagonal slice is proposed. Due to consistency of oscillation mode in FOMMC diagonal slice and original oscillation, as well as its natural blindness to Gaussian signal, accurate detection and correct diagnostic can be achieved even under stochastic power fluctuations and low signal noise ratio. Simulation results for East China power grid demonstrated effectiveness, correctness and anti-noise ability of the proposed method.
作者
冯双
蒋平
舒展
吴熙
徐青山
雷家兴
FENG Shuang;JIANG Pingl;SHU Zhan;WU Xi;XU Qingshan;LEI Jiaxing(School of Electrical Engineering,Southe~/st University,Nanjing 210018,Jiangsu Province,China;State Grid Jiangxi Electric Power Research Institute,Nanchang 330096,Jiangxi Province,China)
出处
《电网技术》
EI
CSCD
北大核心
2018年第9期3007-3013,共7页
Power System Technology
基金
国家自然科学基金项目(51577032)
教育部中央高校基本科研业务费专项资金资助项目(2242018K40073)~~
关键词
低频振荡检测
四阶混合平均累积量
振荡类型判别
峰度
detection of low frequency oscillation
fourthorder mixed mean cumulant （FOMMC）
diagnostic ofmechanism of low frequency oscillations
kurtosis.
