https://doi.org/10.15407/iopt.2019.54.139

Optoelectron. Semicond. Tech. 54, 139-148 (2019)

D.V. Pekur

TWO PHASE COOLING SYSTEMS OF VOLUMETRIC LED MODULES FOR RETROFIT LAMPS

The article is about the problem of creating powerful LED light sources. At present time, most household lighting fixtures and much of the industrial ones are using lamps of various types intended for installation in the lampholder. Such lighting products have the design and technical characteristics intended for use in them lamps with traditional sources of light - incandescent, fluorescent, halogen or metal-halide lamps. In order to preserve the luminous design of such lighting devices and to increase their luminous efficiency, it is important to create lamps based on solid - state light sources with a distribution of light close to traditional lamps - retrofit lamps.

Consideration is given to the usage of heat pipes reducing the temperature of the LEDs in the designs of retrofit lamps. The usage of heat pipes as an element of the heat sink holder significantly reduces the temperature difference between the LEDs and the heat exchange system with the air (radiator), even at a considerable length of the holder, while maintaining its small mass and overall characteristics. Placing LEDs on a voluminous module as a heat sink holder used by heat pipes increases the angles of spatial distribution of light across the bulb of the lamp without the use of lenses, and thus reduces the number of structural elements, while maintaining the low temperature of the LEDs, which increases their light efficiency and lifetime. This paper explores and compares experimental samples of three-dimensional LED modules of different designs. The analysis of the results showed that the proposed design of powerful LED retrofit lamps with cooling systems based on heat pipes is able to provide optimal temperature modes for operation of the LEDs, even with a significant increase in lamp power. The thermal resistance between the LED body and the radiator was reduced 6.8 times. The expediency of using LEDs with low thermal resistance between the crystal and the housing in cooling systems based on heat pipes is shown. The developed design with the usage of LEDs with low thermal resistance allowed to improve the thermal conditions of the LEDs and to increase the prototype power of high-power lamps by 136% without increasing the size of the radiator of the cooling system.

The results of the study can be used to create super-power lamps which use heat pipes in the cooling systems.

Keywords: voluminous light-emitting diode modules, cooling, retrofit lamp, heat pipes.