Fault Diagnosis Of Dlanetary Dearbox Dased On Donstationary Dignal

At present, many large mechanical equipments require a large transmission ratio to transmit power, and planetary gear transmission system is one of the most widely used transmission components. It is widely used in ships, aircrafts, wind turbines and other equipments. Planetary gear transmission system is a complete system. If there is a problem in the structure of the key components, it will affect other components, and the whole system will stop working, which may lead an immeasurable economic loss.Planetary gear box is different from a fixed axis gear transmission box. Planetary gear box is composed by several components composition. A single-stage planetary gearing system generally consists of a sun gear, planetary wheels, a gear ring and a planet carrier. Gear ring generally is fixed on the gear box, and the sun gear rotates around its own axis. The planetary gears evenly distributed around the sun gear, and the planetary gears will mesh the sun gear and the ring gear at the same time. Therefore, the movement of the gear box is a typical complex motion, which makes the vibration response more complex than the fixed axis gear box, and leads to the fault diagnosis become difficult. In practice, planetary gear box often works in nonstationary condition. However, the study about the fault diagnosis of the planetary gear box in nonstationary condition is still few. Therefore, it is necessary to analysis the vibration signal and diagnose the planetary gear box in nonstationary condition.Aiming at the difficulties of fault diagnosis of planetary gear box, this thesis has done the following work:(1) Owing to planetary gearbox is the research object, this thesis summes the different vibration theory models of the fault planet gear box, then analyzes the fault characteristic frequency and the fault judgment of the planetary gear box.(2) Focusing on the characteristics of the nonstationary signal, this thesis selects order analysis to analyze the signal. This thesis introduces the theory and application of order analysis, and proves that order analysis is an effective method of the fault diagnosis in nonstationary condition. Then combined with experimental equipment and order analysis, summarys the different orders of the planetary gear box, and analyzes the collected planetary gearbox vibration signal of rotating speed by order analysis. And it achieves the fault diagnosis of the planetary gearbox in nonstationary condition.(3) Due to the frequencies and amplitudes are all non-stationary, this thesis analyzes the theory model and puts forward the relationship between the amplitude and rotational speed of the planetary gear box, and then prove this method by smoothing the experiment data of the planetary gear box which works in nonstationary condition.(4) In view of the unique operating condition of the planetary gear box, this thesis puts forward the order tidal time which can be used for fault diagnosis of the planetary gear box, and uses the tidal order of planetary gear box diagnosis the fault of the planetary gear box.