(1. 中南大学 能源科学与工程学院,长沙 410083;
2. 中铝公司 广西分公司电解厂,百色 531400)
摘 要: 以采集的160 kA铝电解槽阳极的电流信号为基础,利用Yule-Walker方法的功率谱估计对其进行分析,提取不同槽况的频谱特征,并将分析结果与HHT(Hilbert-Huang transform)的边际谱分析结果进行对比。结果表明:基于Yule-Walker方法的功率谱估计分析结果能较好地区分正常糟、冷槽及阴极破损槽,并得到正常糟、冷槽及阴极破损槽功率谱曲线主谱峰的频率范围分别为0.003~0.018、0.023~0.027、0.027~0.031 Hz;对于不同槽况下的阳极电流信号,HHT的边际谱的主谱峰与Yule-Walker方法的功率谱曲线的主谱峰位置一致,表明功率谱估计分析结果的可靠性。
关键字: 铝电解槽;160 kA铝电解槽;槽况;阳极电流;功率谱估计;Yule-Walker方法;边际谱
160 kA aluminum reduction cells in different states
(1. School of Energy Science and Engineering, Central South University, Changsha 410083, China;
2. Aluminum Electrolytic Plants, Guangxi Branch of China Aluminum Co., Baise 531400, China)
Abstract:Yule-Walker method was applied to analyzing the power spectrum of anode current signals collected from 160 kA aluminum reduction cells and to extracting the spectral characteristics in different operation states, and then the power spectrum was further compared with the marginal spectrum resulting from HHT(Hilbert-Huang transform). The results show that the power spectrum based on Yule-Walker method is able to distinguish the normal cell, the cold cell and the cell with local failure of cathode surface, and their frequency ranges are recognized to be 0.003−0.018, 0.023−0.027 and 0.027−0.031 Hz, respectively. For the anode current signals from different cell states, the main peak at the power spectrum curve has the same location as that at the marginal spectrum curve, showing the good reliability of Yule-Walker method for the power spectrum estimation of the anode current signals.
Key words: aluminum reduction cell; 160 kA aluminum reduction cell; cell state; anode current; power spectral estimation; Yule-Walker method; marginal spectrum