铝电解槽电阻信号的小波包分析

Study on Resistance Signal of Aluminium Reduction Cells Applying Wavelet Packet

铝电解槽是典型的非线性复杂系统,具有高温、强电磁场、强腐蚀性、时变性、在线连续检测量少等特征,而槽电阻信号是电解槽控制的关键变量.对槽电阻信号进行预处理后,首次采用四层小波包变换对其进行分析,以分解后的各小波系数的模构建了特征向量;通过计算特征向量间的欧式距离,提取出阳极效应前和正常期的槽电阻高频特征信息.这为提前作出阳极效应预报及控制提供了新途径.

Electrolytic cell is typically nonlinear and complex system with high temperature and strong electromagnetic fields. It is also highly erosive and time-varying. The online measurable variables are also very limited. The cell resistance is a key variable for the cell control. In this paper, a four-layer wavelet transform is used to analyze the pre-processed cell resistance signal. The norm of the wavelet coefficients after decomposition is then used to construct the characteristic vector. The Euclidean distance between the characteristic vector is calculated to extract the high frequency information from the resistance signal prior to and after the anode effect. A new method for forecast and control of anode effect is provided.