An ultrasensitive self-powered smart bearing pedestal with fault locating capability

Abstract

For bearing condition monitoring, commonly used measuring points on the casing suffer from low signal-to-noise ratios and strong interference. These issues are expected to be addressed through embedded wireless sensors. To tackle the challenges faced by wireless sensor nodes in terms of energy supply and to enhance their intelligence level, this paper proposes a self-powered smart bearing pedestal with ultrasensitive sensing capabilities. The proposed bearing pedestal features a segmented arrangement of piezoelectric stacks integrated into the structure, utilizing the varying contact load generated by rolling elements. To evaluate the operating characteristics of the smart bearing pedestal, an electromechanical coupling dynamic model is developed, upon which dynamic analysis is carried out for both healthy and faulty bearings. Subsequently, a smart bearing pedestal prototype is manufactured and rotor tests are conducted to further investigate the performance of the proposed smart bearing pedestal. It is observed that the test data aligns well with the simulation results. The smart bearing pedestal has condition monitoring and fault detecting capabilities of high sensitivity, allowing it to sense bearing rotational speed and identify faults of different bearing components, as well as localize the defects on the outer ring. Additionally, it exhibits excellent power supply performance, with a quite low internal resistance of approximately 100 Ω, and is capable of generating an electrical output of 525.9 μW at the rotating speed of 1800 rpm. This research provides a new solution for smart bearing support systems, contributing to intelligent sensing in rotating machinery.