基于EEMD和MFFOA-SVM滚动轴承故障诊断

针对滚动轴承发生故障时，振动信号的时域和频域特征都会发生变化的特点，提出了基于集合经验模态分解（EEMD）、改进果蝇优化算法（MFFOA）和支持向量机（SVM）的滚动轴承故障诊断方法。该方法主要是利用EEMD方法对故障信号进行分解，并计算各IMF分量的均方根值和重心频率，以此进行归一化处理得到特征向量。为了提高诊断精度，采用果蝇优化算法优化SVM参数，建立MFFOA-SVM模型，然后对提取的特征向量进行训练与测试，从而识别故障与否及发生点蚀故障的程度。利用该方法对实测信号进行分析与诊断,并与遗传算法的优化结果进行对比，验证了该方法的有效性，说明其具有良好的应用前景。

Study on Rolling Bearing Fault Diagnosis Based on EEMD and MFFOA-SVM

Both of the time domain and frequency domain of the vibration signals would be changed when rolling bearing faults occured. A rolling bearing fault diagnosis method was proposed based on EEMD, MFFOA and SVM. EEMD was used to decompose the fault signals, and to calculate the root mean square value and frequency of the center of gravity, achieving the normalization processing feature vector. In order to improve the classification accuracy rate, a MFFOA-SVM model was built, and then the feature values were extracted for training and testing, so that it might recognize the faults or not and the degree of pitting corrosion failures. The actual signals were analyzed and diagnosed, and compared with genetic algorithm optimization results, it proves the validity of the method, and the improved method has a good prospect for its applications in rolling bearing diagnosis.