用小波包变换检测永磁直线同步电机系统的弱信号

分段式永磁直线同步电机垂直提升系统解决了单段型动子需要拖线的供电方式,但是系统信号却较难检测。文中分析了小波包变换具有良好的时频特性的特点,并根据信号和噪声具有不同的小波特性,采用浮动阀值去噪的方法,解决了低信噪比情况下弱信号的检测。

Weak Signal Detection of Permanent Magnet Linear Synchronous Motor Operating in the Vertical Elevating System by Means of Wavelet Packet Transform

The vertical elevation system composed with each segmental permanent magnet linear synchronous mo-tor solves problem that the power supply of single segmental moving part has to be equipped with the dragging cable but the signal of the system is actually more difficult to detect,however,the job site has the massive unwanted signal. The paper analyses the excellent time-frequency localiza-tion properties of wavelet packet transform according to the different wavelet properties between the signal and noise and realizes the weak signal detection by means of floating threshold denoising based on wavelet packet transform.