摘要
随着风电的快速发展,其规模化接入会对系统的低频振荡带来较大的影响,采用希尔伯特-黄变换法（HilbertHuang transform,HHT）分析风电功率波动及其对电力系统低频振荡的影响。将风电功率进行经验模态分解（empirical mode decomposition,EMD）,采用HHT变换和曲线拟合,进而得到不同振荡模态的阻尼比,以此作为低频振荡的判断依据。以WSCC 3机9节点系统模型为例,对比分析同幅值不同频率和同频率不同幅值的标准正弦风电功率波动对系统低频振荡的影响。针对实际风电功率,根据波动率和能量密度可知功率的波动集中于中频段（0.01~1 Hz）,因而对系统低频振荡的影响更为严重,对风电功率波动的平抑成为必要。
With the rapid development of wind power, its large-scale integration and long-distance transmission will bring significant impact on power system low frequency oscillation（LFO）. A method evaluating wind power fluctuation characteristics and its impact on power system LFO based on Hilbert-Huang Transform（HHT） is proposed. Firstly, wind power was decomposed with empirical mode decomposition（EMD） into a series of stable signal with different frequencies. Secondly, the damping ratios of different modes were acquired through HHT. Then system LFO type and features were obtained. The WSCC 3-machine 9-bus power system is employed to investigate the impact of typical sinusoidal wind power fluctuations on power system LFO, including different frequencies with identical amplitude, and different amplitudes with identical frequency respectively. Since wind power fluctuations rate and energy density of an actual wind farm mainly concentrate in medium frequency band（0.01-1Hz）, the LFO of power system will be deteriorated. Therefore, wind power fluctuations should be suppressed properly.
出处
《电网技术》
EI
CSCD
北大核心
2015年第8期2115-2121,共7页
Power System Technology
基金
国家重点基础研究发展计划项目(973项目)(2012CB215200)~~
关键词
希尔伯特-黄变换
波动率
阻尼比
低频振荡
HHT
rate of power fluctuations
damping ratio
low frequency oscillation
