To solve the problem that the weak fault signal is difficult to extract under strong background noise, an asymmetric second-order stochastic resonance method is proposed. By adjusting the damping factor and the asymmetry, weak signals, noise, and potential wells are matched to each other to achieve the best stochastic resonance state so that weak fault characteristics can be effectively extracted in strong background noise. Under adiabatic approximation, the effects of damping coefficient, noise intensity, and asymmetry on the output signal-to-noise ratio are discussed based on the two-state model theory. Under the same parameters, the output signal-to-noise ratio of the asymmetric second-order stochastic resonance system is better than that of the underdamped second-order stochastic resonance system. The bearing fault and field engineering experimental results are provided to justify the comparative advantage of the proposed method over the underdamped second-order stochastic resonance method.

中文翻译：

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非对称二阶随机共振弱故障特征提取方法

针对强背景噪声下微弱故障信号难以提取的问题，提出了一种非对称二阶随机共振方法。通过调整阻尼因子和不对称性，使弱信号、噪声和势阱相互匹配，达到最佳随机共振状态，从而在强背景噪声中有效提取弱故障特征。在绝热近似下，基于二态模型理论讨论了阻尼系数、噪声强度和不对称性对输出信噪比的影响。在相同参数下，非对称二阶随机共振系统的输出信噪比优于欠阻尼二阶随机共振系统。