Debris Recognition Methods in the Lubrication System with Electrostatic Sensors

Abstract

The oil-line electrostatic sensor (OLS) is a developing debris monitoring sensor. Previous work has shown that electrostatic charge signals can indicate the debris by calculating the Root Mean Square (RMS) value or the correlation-based indicator, but the precision of these methods is not high. This paper further developed the more accurate methods to obtain detailed debris information. Firstly, to interpret the monitoring principle of OLS and provide the guidance for developing the debris recognition methods, this paper analyzed the possible charge sources in the lubrication system and obtained the characteristics of the OLS by establishing its mathematical model. Further, a new OLS test rig was designed and verified the correctness of the sensor’s characteristics and its mathematical model. Based on the characteristics of the sensor, two new debris recognition methods were proposed. Finally, the effects of the new debris recognition methods were verified by the practical industrial gearbox bench test. Results showed that, compared to the traditional methods, the new methods could recognize the debris effectively and provide more detailed information of the debris.

Numerical analysis and experimental verification of the induced waveform characteristics for aeroengine gas path debris electrostatic sensor

“…The researchers who apply electrostatic sensors with ring probe to monitor debris in the oil give this definition. [24][25] This study also uses this definition. Calculate Qf and T, and the results are shown in Table 1:…”

“…The characteristic analysis of the induced charge waveform is also the basis of the particle recognition technology. 24 However, detailed analysis on the induced charge waveform characteristics of the aeroengine debris electrostatic sensor has not been reported.…”

Electrostatic sensors – Their principles and applications

“…To optimise the design of the electrostatic sensors for oil lubricated tribological systems, Liu et al [114] developed mathematical models of the ring-shaped electrostatic sensor and investigated its sensing characteristics, including spatial sensitivity, sensor efficiency, static sensitivity and electrostatic field of view. Through analyzing the possible charge sources in the lubrication system, Mao et al [115] proposed two debris recognition methods based on the amplitude and pulse width of the sensor signal and general extreme value distribution. However, the methods only work when the gearbox is in a stable working condition.…”

Research on Electrostatic Monitoring of Tribo-Contacts with Dynamic Adaptive Fusion Method

“…Later, it is introduced to apply in the friction and wear of mechanical systems with researches on the monitoring of sliding rolling and bearing wear systems [17][18][19][20]. After a series of experimental works, the electrostatic monitoring technique has been proved to be effective with its high sensitivity in condition monitoring of tribo-contacts [21][22][23][24]. Unlike conventional monitoring methods such as temperature and vibration that measure the secondary effects of wear, electrostatic monitoring is a direct measurement with detected electrostatic charges to the wear components by using electrostatic sensors [25][26][27].…”