Catching Critical Transition in Engineered Systems

Figure 2

The Fluctuation Mining (FM) process and the identification of intrinsic stochastic fluctuations. (a–c) The processing flow of FM on the collector current of the IGBT system. (a) A snippet of the time series of collector current collected from the IGBT system. (b) The failure-sensitive component, i.e., the switch-off current that exponentially converges to 0, in the collector current. (c) The fluctuations derived after performing FM on the previous snippet of the time series. (d) The original time series of collector current collected from the IGBT accelerated aging test. (e) The fluctuations derived after FM for (d). (f–h) The variance, autocorrelation, and skewness indicators after FM. Analysis of the signals after the FM process shows strong evidence of CSD and deviating skewness.

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