基于Park-HHT的故障特征提取方法

针对三相对称系统,提出了一种新的故障特征提取方法。该方法首先将系统输出信号进行Park变换,之后进行希尔伯特-黄变换(Hilbert-Huang transform, HHT),从HHT的本征模态函数中选取低频分量,提取信号幅度作为故障特征值。该方法兼具Park变换和HHT的优点,在降低变量维度的同时提高了故障分辨率,并且具有较强的抗噪声能力。最后,在三相逆变电路中进行了仿真实验,根据特征向量间距离分布对不同方法的提取效果进行评价,验证了所提方法的有效性。

Fault feature extraction method based on Park-HHT

A new fault feature extraction method is proposed for three-phase symmetric system. Firstly, the three-phase output signal of the system is firstly Park transformed by the method, and then the signal goes through Hilbert-Huang transform (HHT). The low-frequency component is selected from the eigenmode function of HHT and the signal amplitude is extracted as the fault characteristic value. This method has the advantages of both Park transformation and HHT, which can improve the fault resolution while reducing the variable dimension, and has a strong anti-noise capability. Finally, the simulation experiment is carried out in the three-phase inverter circuit, and the extraction effect of different methods is evaluated by using the distance distribution between feature vectors, which verify the effectiveness of the proposed method.