Small sample reliability assessment with online time-series data based on a worm WGAN learning method

The scarcity of time-series data constrains the accuracy of online reliability assessment. Data expansion is the most intuitive way to address this problem. However, conventional, small-sample reliability evaluation methods either depend on prior knowledge or are inadequate for time series. This article proposes a novel auto-augmentation network, the worm Wasserstein generative adversarial network (WWGAN), which generates synthetic time-series data that carry realistic intrinsic patterns with the original data and expands a small sample without prior knowledge or hypotheses for reliability evaluation. After verifying the augmentation ability and demonstrating the quality of the generated data by manual datasets, the proposed method is demonstrated with an experimental case: the online reliability assessment of lithium battery cells. Compared with conventional methods, the proposed method accomplished a breakthrough of the online reliability assessment for an extremely small sample of time-series data and provided credible results.