基于双谱的风电引起强迫振荡模式相关性分析

Correlation analysis of forced oscillation modes induced by wind power based on bi-spectrum

风机并网容量的增加表明新能源替代正在逐步发展,但含风电的非线性系统可能会激励多模式的强迫振荡,其深层次关系难以用传统方法分析。文中首先由组合风速模型分析了风电引起强迫振荡可能拥有的特性;其次引入了高阶统计量中的双谱分析和双相干分析,所得双谱和双相干系数用于分析风电引起的振荡和振荡之间的二次相位耦合关系;最后在四机两区算例中接入小型风电场进行仿真。仿真结果验证了所提推测的正确性和所提方法的有效性。

The increase of the grid-connected capacity in wind turbine indicates that the renewable energy alternative is gradually developing.However,the nonlinear system containing wind power may stimulate multi-mode forced oscillation,whose deep relationship is difficult to analyze by traditional methods.In this paper,the characteristics of wind-induced forced oscillations are analyzed firstly based on combined wind speed model.Secondly,bi-spectral analysis and bi-coherence analysis in high-order statistics are introduced.The obtained bi-spectrum and bi-coherence coefficients are used to analyze the oscillation caused by wind power and the quadratic phase coupling level between these oscillation modes.Finally,the simulation is operated in the four-generator two-zone system with a small wind farm.The simulation results verify the correctness of the proposed speculation and the effectiveness of the proposed method.