电厂开关柜局部放电振动信号降噪方法研究

针对电厂开关柜运行环境复杂,振动干扰较强,又需要保留振动干扰、分析振动干扰特征的问题,将基于相空间重构的ICA降噪方法应用到电厂开关柜局放振动信号中,进行信噪分离。首先依据相空间重构,在不破坏信号本身动力学特征的情况下构造高维相空间矩阵。然后利用独立分量分析方法进行信噪分离,提取有用振动信号。仿真信号和实际检测数据的应用表明,所提方法与小波法降噪能力相当,甚至更优;且不需要考虑最优小波基和最佳分解层数,自适应强,易于实现;且适用于电厂开关柜局放振动信号降噪。

Study on de-noise method for partial discharge vibration signal of switch cabinet of power plant

In view of the problems of power switch cabinet such as complex operating environment, strong vibration disturbance, and needing to retain the vibration disturbance and analyze the characteristics of vibration disturbance, the Independent Component Analysis (ICA) de-noise method based on phase space reconstruction is applied to the partial discharge vibration signal of the switch cabinet of the power plant, and the signal separation is carried out. First, according to phase space reconstruction, this paper constructs the high dimension phase space matrix without destroying the dynamical characteristics of the signal itself. Then the independent component analysis method is used to separate the signal from the noise and extract the useful vibration signal. The application of the simulation signal and the actual data shows that the method is equivalent to or better than the wavelet method in de-noise. Besides, the optimal wavelet base and the optimal decomposition layer are not considered, and the self adaptation is strong and easy to implement. It is also suitable for de-noise of partial discharge vibration signals of switch cabinet of power plant. This work is supported by Key Science and Technology Project of Jiangsu Electric Power Company (No. J2017070).