结合自适应最稀疏时频分析(ASTFA)和广义解调的优点提出了基于ASTFA的广义解调方法。该方法首先采用ASTFA对原始信号进行分解,得到分量信号及其相位函数;然后,提取该相位函数的二次项及高次项,获得解调相位函数;之后利用解调相位函数对分量信号进行广义解调;最后对广义解调后的信号进行频域分析,提取特征信息。仿真和实验分析结果表明,基于ASTFA的广义解调方法非常适用于处理多分量频率调制信号,能够有效提取滚动轴承在变速工况下的故障特征信息。
Combining with the advantages of the ASTFA and the generalized demodulation, a generalized demodulation method was proposed based on the ASTFA. Firstly, the original signals were decomposed via ASTFA,and the component and its corresponding phase function were obtained. Secondly, the demodulation phase function was formatted by extracting the secondary and higher or- der terms of the phase function. Then, the generalized demodulation method was applied to the com- ponent using the demodulation phase demodulation function. Finally, the frequency domain analyses were applied to the demodulated component to extract feature information. Simulation and experimen- tal analyses show that the method is very suitable for processing multi-component frequency modulated signals, and can effectively extract the damage characteristic informations of the rolling bearing damages in shifting conditions.