Thermal Performance Comparison of Thick-Film Insulated Aluminum Substrates With Metal Core PCBs for High-Power LED Modules

LED has been regarded as the next generation lighting source. As for high power LED lamps, heat accumulation will cause a series of problems. Therefore, thermal management is very important for designing a high power LED lamp. Three types of heat sinks are designed by using the finite element analysis (FEA) method for an 180W high power LED lamp. Then the optimized heat sinks are developed and experiments are performed to demonstrate the simulated results. At the same time, the thermal performances with different working angles are investigated experimentally. The heat sink with heat pipe has a better heat dissipation performance than the conventional heat sink under the same input power. The working angles of the lamps greatly influence the thermal performance of each heat sink. For the same heat sink, the temperature varies with different install directions and working angles. Finally, the heat sink with the best thermal performance is recommended. The results have practical significance in designing high power LED lamps.

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Thermal Management for High Power Light-Emitting Diode Street Lamp

Volume 4: Electronics and Photonics ◽

10.1115/imece2010-38557 ◽

2010 ◽

Author(s):

M. Ying ◽

S. M. L. Nai ◽

P. Shi ◽

J. Wei ◽

C. K. Cheng ◽

...

Keyword(s):

Thermal Management ◽

Thermal Performance ◽

High Power ◽

Heat Dissipation ◽

Light Emitting Diode ◽

System Level ◽

Light Emitting ◽

High Power Led ◽

Street Lamp ◽

Lamp System

Light-emitting diode (LED) street lamp has gained its acceptance rapidly in the lighting system as one of choices for low power consumption, high reliability, dimmability, high operation hours, and good color rendering applications. However, as the LED chip temperature strongly affects the optical extraction and the reliability of the LED lamps, LED street lamp performance is heavily relied on a successful thermal management, especially when applications require LED street lamp to operate at high power and hash environment to obtain the desired brightness. As such, a well-designed thermal management, which can lower the LED chip operation temperature, becomes one of the necessities when developing LED street lamp system. The current study developed an effective heat dissipation method for the high power LED street lamp with the consideration of design for manufacturability. Different manufacturable structure designs were proposed for the high power street lamp. The thermal contact conductance between aluminum interfaces was measured in order to provide the system assembly guidelines. The module level thermal performance was also investigated with thermocouples. In addition, finite element (FE) models were established for the temperature simulation of both the module and lamp system. The coefficient of natural convection of the heat sink surface was determined by the correlation of the measurement and simulation results. The system level FE model was employed to optimize and verify the heat dissipation concepts numerically. An optimized structure design and prototype has shown that the high power LED street lamp system can meet the thermal performance requirements.

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Thick Film Approaches in High Power LED Array Module

Additional Conferences (Device Packaging HiTEC HiTEN & CICMT) ◽

10.4071/cicmt-2011-tp33 ◽

2011 ◽

Vol 2011 (CICMT) ◽

pp. 000130-000133

Author(s):

Hyo Tae Kim ◽

Jihoon Kim ◽

Young Joon Yoon ◽

Chang Yeoul Kim ◽

Jong-hee Kim ◽

...

Keyword(s):

Heat Transfer ◽

Thick Film ◽

High Power ◽

Light Emitting Diode ◽

Life Time ◽

Operating Voltage ◽

Operation Temperature ◽

Led Array ◽

High Power Led ◽

In Series

Light emitting diode, LED, has become a popular device for display and lighting applications. Among them, high power LED array modules are especially interested in the field of street light system, recently. High power LED array module is generally consisted of several pieces of LEDs which are mounted on the PCB with the combination of series and parallel circuits according to the designed operating voltage and power consumption, i.e. total wattages. Since the life time expectancy and brightness of LED are greatly influenced by the operation temperature of LED, thermal management technology of LED module including system design, heat transfer and dissipation become a hot issue in these days. In this work, we would like to present several thick film approaches to fabricate thermally efficient high power, i.e. LED array modules with over 50 watts by using different array package design, materials selection and film forming techniques. Here, we will demonstrate 50 watts LED array modules directly coupled with aluminum, copper or silicon heat sinks which operates at 12volts using 4 × 9, 4 pieces of LED in series multiplied by 9 arrays in parallel, LED array circuit. The microstructure of metal-ceramic multilayers and interfaces, and the heat transfer performance of the LED array modules will be presented.

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