Weak signal detection based on differential oscillator

The fault characteristic signals of rolling bearings are in low frequency band, and the useful signals are often buried in heavy noise and difficult to be detected. So a new weak signal detection method based on differential oscillator is proposed. Differential oscillator is a kind of signal detection method based on two-dimensional linear differential equations. When measured signals contain the frequency component- fd, the phase diagram converges to the polar ring, otherwise it converges to the poles. The early system fault can be visually detected according to the change of the phase diagram. Based on the introduction of the setup principle of oscillator system parameter, this paper recommends and first analyzes the influence of noise on the oscillator phase diagram emphatically. The simulation signal and the incipient outer ring of the deep grove ball bearing are precise detected by this method.