Life Estimation of DC-Link Capacitor in Multi-operating Traction Drive System

The reliability of DC-link capacitor in the traction drive system is regarded as a major problem that should be resolved well. Based on this, this paper proposes a life estimation method of DC-link capacitor to realize the reliability evaluation of the traction drive system. Starting from the capacitor life model, the actual multi-operating data is converted into the calculation of traction load through simulation tests, and the capacitor voltage and current ripple signals are obtained. Fourier method by combining the sliding window grouping with the neural network are used to analyze the dynamics of the hot spot temperature, and is optimized by use the Newton's law of cooling. Finally, the capacitor loss is analyzed through the experimental test results, and the safe operation of the system is considered, and the lifetime of the capacitor under multi-operating conditions is shown.