Lightweight Hybrid Additively Manufactured Liquid Cooler for 10 kV SiC MOSFET Power Module

Medium-voltage silicon carbide (SiC) power modules are central to high-power-density converters for electrified transportation, aerospace propulsion, renewable energy systems, medium-voltage motor drives, and solid-state transformer in data centers. However, the elevated heat fluxes generated by medium-voltage SiC devices impose stringent thermal management requirements while system-level mass constraints increasingly motivate lightweight cooling solutions. Prior work demonstrated a multi-tier liquid cooling architecture for a 10 kV SiC MOSFET power module featuring stacked substrates and an additively manufactured metallic cooler. Building upon this platform, this work investigates a lightweight hybrid liquid cooler that replaces the aluminum manifold with a 3D-printed nylon manifold while retaining the AlSi10Mg heat transfer core. The hybrid cooler is experimentally evaluated against the original fully metallic cooler using pressure drop measurements, thermal resistance characterization, and infrared thermography. Results show that replacing the aluminum manifold with nylon reduces the cooler mass by 51% while maintaining similar hydraulic performance across the tested flow range. The thermal resistance increases moderately due to the reduced thermal conductivity of the polymer structure and reduced parasitic thermal spreading through the manifold. The results demonstrate the feasibility of hybrid polymer-metal cooling architectures for medium-voltage power electronics applications where gravimetric thermal performance is a critical design consideration, including electrified aircraft propulsion systems and mobile power converters.