Thermal management for LED headlights

Thermal management for LED headlights

Energy-saving lighting demands new solutions

LED headlight ventilation with the 622 M compact fan from ebm-papst

The power density of modern LEDs makes it possible to use this type of lighting in vehicle headlights. The actual light source is insensitive to vibration and shocks. But like any other electronic component, it also needs to be operated within certain temperature limits. Small fans specially adapted to the needs of headlight operation offer a solution. To adapt the headlight to the car's needs, all components need to fulfil a few basic requirements. This also applies to the fans that are used.

Legislation only allows LED lamps in cars as self-contained units. If even one LED fails, the entire headlight must be replaced. So it is important for all components to be durable and perform reliably. At an efficiency of approximately 30%, LEDs also produce considerable waste heat – on a very small chip surface. Even in an energy-saving LED headlight housing, with several LED chips the amount of heat to be dissipated adds up to a few watts quickly. If the chip gets too hot, the service life and light output both suffer. Small fans that are powerful yet smooth-running and durable help to direct the cooling airflow with pinpoint accuracy to protect the electronics. Ruggedly designed fans that can stand up to vibrations, shocks, heat and cold (-40 to +120°C) are called for in the closed headlight housing. They emit no chemicals that could be deposited on the optics and reduce the light output. Special grease lubricates the ball bearings dependably even after 10 years under all climatic conditions.

The design principles of modern LED headlights call for reliable thermal management. Small, rugged fans exactly tuned to the specific characteristics of the vehicle and of LED technology ensure reliable dissipation of excess heat, allowing trouble-free headlight operation for more than a decade. The very tight integration of optics, electronics and cooling in an LED headlight calls for early design consultations among all specialists to ensure optimum results in terms of economic and lighting efficiency.