A REVIEW ON THERMAL MANAGEMENT FOR HIGH POWER LED STREET LIGHTS
Pushparaj Singh, Rohit Tiwari
High-Power LEDs, Heat Pipe, Numerical Simulation, Thermal Management, Fins
Light-emitting diode (LEDs) have a promising prospect because of its outstanding advantages: 1) long lifetime, 2) environmentally friendly, 3) flexibility of color mixing, 4) high illumination efficiency, etc. Based on the electrical characteristics of LEDs, a constant current driver is needed to support the LED working performance. The scope of this review paper is to consolidate various thermal factors which affect the performance of high power LEDs and also to summarize various cooling methods which improve both the efficiency and lifetime of LED lamps.
Thermal factors such as thermal resistance, thermal spreading resistance, and thermal interface material, and thermal capacitance, active and passive cooling systems suitable for high power LED packages are discussed. The effect of junction temperature on the colour of emitted light and life of LED is also explored. Junction temperature of the LED depends on the current supplied and type of cooling system used. Higher junction temperature with poor cooling leads to shift in the light colour and drastically reduces the LED life. From the review it was found that heat sink and heat pipes are best solution for heat dissipation.