Thermal Uniformity Improvement of High Power LED Street Lamp Using Nonuniform Distribution Design of LEDs

摘要

Light emitting diode (LED) street lamp heavily relies on successful thermal management, which strongly affects the optical extraction and the reliability/durability of the LED lamp. In this study, the two-dimensional temperature profile of a high power LED street lamp with traditional uniform distribution of LEDs is calculated, which shows that there is a higher temperature in the central region of the heat sink. For the 196 watts LED street lamp, the peak heat sink temperature was about 53.2°C at the environment temperature of 20°C. With the aid of the theoretical analysis, an optimized structure of LED street lamp with nonuniform distribution of LEDs is presented. The peak temperature is lowered by 1°C compared with that of the uniform one. And the temperature difference within 0.1 °C in the surface of aluminum plate. The improvement above is ascribed to the nonuniform distribution of LEDs, and hence suppressing the heat flow from adjacent area to the central area. Therefore, the calculated results verify that the optimized structure of high power LED street lamp with nonuniform distribution of LEDs is superior to the uniform distribution of LEDs for enhancing the thermal uniformity of LED street lamp.