Energy Conversion and Management, Vol.101, 532-540, 2015
Experimental study on the thermal management of high-power LED headlight cooling device integrated with thermoelectric cooler package
In view of the characteristics of high power light-emitting diodes (LEDs), such as strict junction temperature (T-j) control, the enhanced cooling models based on the thermoelectric cooler (TEC) were presented to meet the thermal demand of high-power LED headlight. The cooling performance of different devices (air cooling & TEC, liquid cooling & TEC) was evaluated and compared by measuring the LED case temperature. Details of the heat transfer performance, particularly, the start-up performances of the TEC cooler, as well as the influence of the fan rotate speed or liquid velocity on the system thermal performance were obtained. It was found that the thermal performance had been elevated dramatically due to the reduction of the hot side temperature, and the thermoelectric cooler was more sensitive to the external fan speed or liquid velocity than purely air cooling or liquid cooling. In addition, the optimal current for air cooling & TEC was 3A, and 5A for liquid cooling + TEC. Investigations of the simulated ambient temperature on junction temperature, forward voltage, and output light were conducted. Results indicated that the case temperature changed linear basically with the increase in heating power or the simulated ambient temperature. When the ambient temperature was within its severe level (60-65 degrees C), the junction temperature could be calculated to 59.5 degrees C, and the corresponding output light was 1607.3 lm. (C) 2015 Elsevier Ltd. All rights reserved.