Car owners are continuously replacing their Halogen headlights with the more efficient LED headlights. LED headlights are known to provide better lighting solution and also lasts over a longer period of time as compared to halogen headlights. The only disadvantage with LED headlights is the extreme heat. LED headlights components to create a considerable amount of heat which needs to be dissipated in order to maintain optimal light output and to increase or maximize the headlights operating life. As a way to extend the brightness and LED headlights performance, LED’s within your car come equipped with either an active cooling mechanism or passive cooling mechanism.
Passive cooling which makes use of heat sinks is sufficient for normal LED’s. On the other hand, designers who make high brightness and power LED’s can also consider active cooling. However, forced air cooling comes with a higher level of complexities. In this post, we will see the relationship between heat and LED performance, passive and active cooling, pros and cons of headlights equipped with fans and pros and cons of headlights without fans.
The amount of heat generated by LED headlights can have a considerable impact on its performance and longevity. There are three important reasons to keep the LED headlights as cool as possible. These reasons are as follows.
The first important reasons are related to the radiant power of LED. The radiant power varies as the function of its junction temperature. As the ambient temperature increases, the junction temperature also increases. And when the junction temperature of the LED increases, the forward voltage as well as the lumen output of the LED decreases.
When the LED is operated with its maximum rated junction temperature, it can initiate a variety of different stress mechanism which in turn will reduce the operating life or longevity of your vehicles LED headlight.
When the LED headlight in your vehicle has a high junction temperature, it reduces your LED headlights color rendering index. The color rendering index (CRI) is a measure of how true the color of LED headlight is when compared with industry standards.
In addition, when the heat within your vehicle is properly managed, it has several benefits. When the heat is effectively dissipated, it can reduce your total cost of LED system by avoiding frequent replacement. It also allows the LED’s to operate at an optimal power level, which reduces the number of LED’s required within your vehicle to achieve industry specified brightness.
Passive Cooling
The main advantage of the passive cooling mechanism lies in the low financial cost and better energy efficiency. This makes it an astute design choice for designers when it comes to heat management for LED headlights. It achieves high levels of heat dissipation by using a heat sink that maximizes the convection and radiation heat transfer modes. Passive cooling uses natural sources like wind to absorb or dissipate heat. This in return performs proper cooling of LED headlights and allows it to be maintained at optimal operating temperatures.
Active Cooling
On the other hand, active cooling mechanism relies on the external sources to provide heat dissipation or transfers. Inactive cooling method, the rate of fluid flow enhances during convection. This increases the rate at which heat is dissipated or removed. It is a forced way to remove heat by using fans and to achieve high levels of optimal operating temperatures. However, the major disadvantages of using active cooling mechanism are the higher operating costs of LED headlights.