BLDC Controller Cooling: Is a Heatsink Necessary?

If you're working with BLDC controllers, you've probably noticed they can get warm during operation. This is quite normal, as components like MOSFETs generate heat while switching currents to drive the motor. A little warmth is usually fine, but too much heat might affect performance or even shorten the controller's lifespan.

So, do you always need to add a heatsink? Well, it depends. In lower-power applications—like small fans, lightweight drones, or low-torque projects—many controllers are designed to dissipate heat through the PCB and their housing. If the controller feels warm but operates stably without cutting out, it may not require extra cooling.

However, as power demands rise—for instance, in e-bikes, electric scooters, or power tools—heat generation can increase significantly. In such cases, a heatsink can be a helpful and straightforward solution. Made typically from aluminum, a heatsink attaches to the hotter components, expanding the surface area for heat to escape into the surrounding air. This passive cooling method is often enough to keep temperatures under control without adding complexity.

There are also other simple ways to help with cooling. Ensuring good airflow around the board, using thermal pads or paste for better contact, and avoiding enclosing the controller in a tight space can make a noticeable difference. Sometimes, even small design tweaks—like mounting the controller on a metal surface—can assist in heat dissipation.

In the end, the need for a heatsink is not always a strict yes or no. It's more about understanding your specific setup, power requirements, and operating conditions. If your controller feels too hot to touch or shows signs of thermal throttling, adding a heatsink is a sensible step toward more reliable and efficient performance. Keep it cool, and your BLDC system will thank you with smoother and longer operation.

Tecote provides comprehensive solutions for BLDC motor controllers. From precision engineering to volume manufacturing, we offer high-performance control boards tailored to your application. Partner with us for expertise that drives innovation. Start the conversation: info@tecote.com.