When junction temperatures of the light emitting diode
(LED) chips packaged inside LED lamps exceed their
maximal limits, the optical extraction and the
reliability/durability of the LED lamps will be jeopardized,
therefore, thermal management is very important for high
power LED street lamps. In this research, a design and
optimization method of horizontally-located plate fin heat
sink was presented to improve the heat dissipation of high
power LED street lamps. To prove the feasibility of the
present design and optimization method, a 112-W LED street
lamp was co-designed by concurrent engineering of optical,
thermal, and stress requirements. The engineering prototypes
were manufactured and experimentally investigated. The
experimental results demonstrated that the maximal heat sink
temperature remained to be stable at 45°C when the ambient
temperature was 25°C, the maximal temperature difference
between steady state temperature and environment
temperature for the heat sink was less than 21°C. Comparing
the results achieved by the design with the ones by the
experiment, it is found that the design and optimization
method is feasible and works well for realizing the
horizontally-located heat sink of such kind of high power
LED street lamp.