An Advanced Power Cycling Test Method for SiC MOSFETs Based on Real-Time Junction Temperature Control

The reliability of Silicon Carbide MOSFETs remains a critical bottleneck for high-performance power converters. While Power Cycling Tests are standard for lifetime assessment, conventional methods generate thermal stress indirectly through open-loop power control. Even some advanced PCTs often rely on pre-calibrated models, leading to a potential mismatch with the true thermal dynamics experienced in diverse applications. To bridge this gap, this digest proposes an advanced Temperature Controlled Power Cycling Test method. The core of Temperature Controlled Power Cycling Test represents a fundamental shift: from controlling the electrical input to directly regulating the primary failure-inducing stressor - the junction temperature. By implementing a high-fidelity, real-time, closed-loop control, the TCPCT platform forces the SiC MOSFET to follow a pre-defined junction temperature profile with high precision. This approach decouples the thermal stress assessment from the specific electrical operating mode, making it a more universal and application-agnostic tool. A prototype has been successfully developed and validated on commercial SiC MOSFETs, demonstrating its capability to accurately replicate application-specific thermal profiles. The results confirm that Temperature Controlled Power Cycling Test provides a more direct, repeatable, and physically meaningful approach to reliability assessment, overcoming key limitations of existing methodologies.