Power Electronics Runs Hot – and Keeps Getting Hotter
Every megawatt of installed solar, every fast-charging pile and every electric drive relies on power electronics that dissipate serious heat. A 60 kW DC fast charger module can push several hundred watts through a single IGBT or SiC power stage, and the heat sink bolted to that module is not an accessory – it is the component that decides whether the device survives its first summer. As SiC and GaN devices shrink package sizes while power density climbs, the thermal budget per square centimetre keeps rising, which is exactly why extruded aluminium heat sinks remain the workhorse of power electronics cooling.
Where Extruded Heat Sinks Do the Heavy Lifting
Extruded profiles cover the three classic power-electronics jobs. First, baseplate heat sinks for IGBT and MOSFET modules: a flat milled base mounts the module while fins carry heat into the airflow. Second, enclosure and duct heat sinks inside inverters and chargers, where long straight fins double as airflow guides. Third, natural-convection heat sinks for smaller drives and power supplies, relying on fin spacing tuned for passive airflow. Compared with die-casting, extrusion wins on medium-to-high fin density, lower tooling cost and faster iteration – three things power-electronics design cycles care about.
Specifying a Heat Sink for Power Electronics
Start from the thermal budget: define the target junction temperature, ambient temperature and airflow, and let the thermal resistance number drive fin height, fin pitch and base thickness. Then pay attention to the three details that decide assembly success: flatness of the mounting face (milled, not as-extruded, to keep thermal interface material thin and even), fin orientation aligned with the airflow direction, and insulation requirements – a 10-25 micron anodised layer provides electrical isolation while keeping emissivity high for radiation cooling. Outdoor chargers and PV inverters also need corrosion protection and, where condensation is a risk, a finish that survives humidity cycling.
From Thermal Design to Production in One Chain
Power-electronics development is iterative: thermal simulation, prototype, test, repeat. A supplier that can turn a revised fin geometry into a new extrusion quickly, machine the mounting face to the required flatness, and anodise to spec – all in-house – keeps each iteration to weeks instead of months. At Siken Aluminum we run extrusion, CNC machining and anodising under one roof, with die development times aligned to power-electronics project cycles. Send us your thermal design or the module datasheet, and we will help you spec the heat sink, then deliver it ready to mount.