Application of high-order differential energy operator in bearing fault diagnosis

Abstract

An alternative energy operator demodulation method named high-order differential energy operator is proposed in this paper. The high-order differential energy operator, unlike previous demodulation techniques, can detect the weak fault bearing signature from a heavily contaminated signal because it can increase the signal-to-noise ratio. Furthermore, this energy operator is also able to suppress vibration interferences. Thus, the operator is more robust than the classical Teager energy operator (TEO) and its improved versions (DESA-1 and DESA-2 for short). Besides, it is also a non-parameter and non-filtering method, so it is easy and straightforward to apply. Finally, the built-in amplitude demodulation (AD) capability eliminates the enveloping step required by most AD methods like TEO and Hilbert transform (HT). The results of simulation tests and bearing fault experiments demonstrate that this method can effectively extract fault features, certifying its superiority in comparison with previous demodulation methods. Therefore, it is more likely to be useful and practical in the field of bearing fault diagnosis, especially in the presence of intense noise and interferences.