LED active cooling system

Posted by shiapeng0220 on January 9th, 2020

In more extreme lighting situations, some type of active cooling may be required. This may be due to high heat flux from nearby leds, small size or surface area that is unable to conduct natural convection, or extremely high ambient temperature conditions. Any of these conditions may change the thermal budget of certain areas and require active cooling systems.

Various "standard methods" for active electronic cooling have been proposed or are also used for leds, although some special conditions apply to active LED cooling.
To date, the led cooling system has used or recommended the use of simple dc rotating fans, thermoelectric coolers (TEC), piezoelectric fans (PZF), synthetic jets (SJ) and liquid cooling (such as microchannels). Each of these has specific advantages, but there are also some disadvantages to the cooling lighting system.

Active cooling of lighting has special requirements that are not required for every semiconductor application. For example, most lighting systems must not produce unpleasant noise levels. This means that any active cooling system must be quiet, and unless precautions are taken, a moving active system can produce unwanted noise.

Other considerations for active optical cooling systems include: 

·  low power consumption --  as efforts continue to improve energy and further increase the energy star rating of LED lamps

· Low sensitivity to dust/external contaminants -- this is a problem for systems with moving parts and airflow

· ability to withstand periodic loads - problematic due to frequent switching on and off of lights

· increased system costs -- a problem that liquid loop systems (such as microchannels) face today

·  service life -- LED products are typically 50,000 hours

For all these problems, is there any reason to consider active cooling? Given how leds glow, the answer is yes. Many leds can increase the light output by increasing the current input until the current saturation point is reached. Today, the most expensive part of an LED system is the LED itself. If the number of leds could be reduced by driving them at a higher current, the cost of the system could be greatly reduced. Increased costs for active cooling systems can actually reduce overall system costs by reducing the number of leds.Therefore, a good active cooling system, if properly designed, is an advantage, which means it must be efficient, quiet, reliable and cost effective.