Damping-regulated GSR array method for multi-harmonic fault diagnosis under variable speed conditions

Abstract Bearing fault diagnosis under variable speed conditions is essential due to the complexities introduced by speed fluctuations. The accurate detection of multi-harmonic faults is critical for ensuring reliability in intricate operating environments. From the perspective of the beneficial effects of noise, in this study we propose a novel damping-regulated generalized stochastic resonance (GSR) array method designed for multi-harmonic fault diagnosis under variable speed conditions. First, we employ computed order tracking to transform non-stationary time-domain signals into stationary signals in the angular domain. A damping-regulated GSR oscillator is then introduced within this domain, forming the basis of our GSR array. By analyzing the system stationary response, we reveal the diagnostic performance in theory to assess the array’s capacity for enhancing multi-harmonic fault characteristics. Through simulations and experimental validation, our method demonstrates superior diagnostic accuracy, particularly in variable speed scenarios. It excels in preserving and enhancing weak multi-harmonic fault characteristics while offering significant advantages in high diagnostic robustness. These findings provide significant potential for practical applications in fault diagnostics across various engineering systems.