Data-Driven AI Model for Railway Vehicle SIV Condition Diagnosis System
摘要
Capacitors in the Static Inverter (SIV), which are essential power conversion devices for railway vehicle operational stability, exhibit a high failure rate due to degradation and breakdown. This reveals the inefficiency of conventional time-based maintenance (TBM) and the limitations of existing diagnosis research conducted in restricted environments. To address these issues, this study proposes a data-driven AI model-based condition diagnosis system for railway vehicle SIV DC-Link capacitors. The proposed system estimates capacitance changes based on voltage, current, and temperature data collected during operation. Essential temperature compensation is applied, especially considering the temperature sensitivity of the externally installed SIV enclosure. For precise diagnosis, a high-sampling-frequency Data Sensing Module (DSM) is installed, and after deriving capacitance, data synchronized with the TCMS is secured for data preprocessing. The collected data are refined through median-based transformation, followed by temperature compensation, to analyze long-term degradation trends. A deep learning-based prediction model is employed to forecast future changes in capacitor state, and the performance of various regression algorithms, including Gradient Boosting, MLP, LSTM, and GPR, is compared. The proposed method was validated through field tests on AC/DC and DC railway vehicles, demonstrating its consistent applicability across different SIV systems and proving it to be a versatile capacitor diagnosis system.