基于EMD和Prony算法的次同步扭振模态参数辨识

Modal Parameter Identification of Subsynchronous Oscillations Based on EMD and Prony Algorithm

从瞬时转速测量数据中有效提取次同步扭振信号,并准确地辨识模态参数,仍有一定的技术难度。提出了通过EMD预处理提取次同步扭振信号,并进行重采样处理,再通过Prony算法辨识次同步扭振模态参数的方法。采用该方法对某电厂扭振实测数据进行了应用分析,并与基于传统滤波器以及小波滤波器的Prony分析结果进行比较。研究表明所提方法能够有效提高次同步扭振模态参数辨识的精度。

It is technically difficult to extract subsynchronous oscillation signals effectively from the transient speed measurements, and identify modal parameters accurately. This paper proposes a method including EMD-based pre- treatment for the signal extraction, resampling processing, and modal parameter identification through Prony algo- rithm. This method was adopted for application analysis of the field oscillation measurements in a power plant, and the analytical results were compared with those based on the conventional wave filter or wavelet filter Prony analysis. It is shown that this proposed method can effectively improve the identification accuracy of subsynchronous oscillation modal parameters.