Thermal Impedance Characterization Using Optical Measurement Assisted by Multi-Physics Simulation for Multi-Chip SiC...

Area of Science:

• Electrical Engineering
• Materials Science
• Thermal Management

Background:

• Accurate thermal impedance characterization is critical for the reliability and performance of silicon carbide (SiC) power modules.
• Traditional methods using temperature-sensitive electrical parameters (TESPs) can be limited by response time and require calibration.
• Fiber optic sensors offer non-intrusive temperature measurements but have slower response times compared to electrical methods.

Purpose of the Study:

• To propose and validate a hybrid approach for determining the thermal impedance of multi-chip SiC power modules.
• To overcome the limitations of slow optical temperature sensors by integrating multi-physics simulations.
• To achieve accurate and reliable thermal resistance analysis without additional calibration.

Main Methods:

• A fusion approach combining fiber optic temperature sensing for junction temperature measurement with multi-physics simulations.
• Utilizing multi-physics simulations to estimate thermal responses during periods not captured by the slower optical sensors.
• Employing network identification by deconvolution (NID) for thermal resistance analysis.

Main Results:

• The proposed fusion method accurately determined the thermal impedance of a multi-chip SiC power module.
• The estimated thermal resistance showed a minimal difference of 3.8% compared to a conventional method.
• The hybrid approach successfully compensated for the slow response of fiber optic sensors.

Conclusions:

• The combined optical measurement and multi-physics simulation method is accurate and reliable for SiC power module thermal impedance determination.
• This technique eliminates the need for additional calibration circuits, simplifying the measurement process.
• The approach enhances the thermal management strategies for high-power SiC devices.