Demodulated resonance technique in fault diagnosis of high speed line rolling-mill synchromesh gears

Normal vibration signal of rotating machinery is low-frequency signal, yet high-frequency component would exist when having fault, especially when the fault is caused by mechanical shock. But the shock pulse is very weak compared to the low-frequency component. Demodulated resonance technique can filter the low-frequency component and keep the high-frequency component. Then generate resonance wave in which the shock pulse is amplified. The signals from the gearbox are coupled to each other which make the fault diagnosis difficult, with multiple sources decoupling technique can detect independent signal of each measuring point. First, construct relative influence coefficient of the system, and then calculate the gain matrix. Adjust the parameters of the matrix repeatedly to eliminate the impact from other points. Finally, the amplified independent shock signal is detected through which the fault can be identified. The application approves that this method is effectively in fault diagnosis and fault location.