Stray Parameter Extraction Method Based on High-Frequency Oscillation: An Experimental Study With Theoretical and Execution Demo

Stray parameter extraction is crucial for the safe operation and stress estimation in power electronics systems. This study proposes a multifaceted stray parameter extraction method based on high-frequency oscillation characteristics of switching transient. Unlike existing methods that rely on waveform amplitude accuracy and channel sampling synchronization, the proposed method requires less precision in these areas. Hence, it is more resilient to signal attenuation and mismatch issues, making it a robust solution. First, the mathematical analysis of the oscillation behavior in the turn-OFF transients is presented. Next, the relationship of the oscillation frequency with the parameters in a second-order and a fourth-order model is analyzed. A novel extraction method and the corresponding design of the extraction kit are then presented. The effectiveness is verified by the extraction application in various components in a high-power converter, including copper and laminated busbars, dc-link capacitors, and semiconductor power modules. The robustness and frequency algorithm were improved and verified by Monte Carlo trials. Both partial and total loop parameter extraction tests validate that the proposed method can accurately obtain values in the order of 10 nH and offers high test precision, simple operation, and low extraction error.