System dynamics model of high-power LED luminaire

Optical properties of LEDs are sensitive to junction temperature. From the principle of solid-state lighting, the luminance of LED is induced from two physical mechanisms: energy effect and optoelectronic effect. Both effects are related to junction temperature. The understanding of system dynamic behavior in junction temperature is quite important for lighting control design. The system dynamics model of a high-power LED fixture for energy effect was derived and identified in the present study using step response method. Both theoretical and experimental analyses have shown that the thermal system dynamics model of the LED fixture is 4th-order with three zeros and can be reduced to a first-order biproper system. The instantaneous jump of junction temperature dominates the thermal behavior of LED at the beginning of the step input. The optoelectronic effect was induced mainly from the current input and the junction temperature. Combining the two physical effects, an electric-heat-optical system dynamics model of LED luminaire was finally proposed which is the basic system dynamics model for LED luminance control.

[1]  Mi Sandar Mon,et al.  Heat Exchanger Design , 2008 .

[2]  J. D. Martin,et al.  Temperature rise and thermal rise‐time measurements of a semiconductor laser diode , 1992 .

[3]  E. Schubert,et al.  Influence of junction temperature on chromaticity and color-rendering properties of trichromatic white-light sources based on light-emitting diodes , 2005 .

[4]  D. H. Mash,et al.  Light-emitting diodes , 1977, Nature.

[5]  M. Pashley,et al.  Red, green, and blue LEDs for white light illumination , 2002 .

[6]  C. Hoelen,et al.  Achieving color point stability in RGB multi-chip LED modules using various color control loops , 2005, SPIE Optics + Photonics.

[7]  E. Gray,et al.  Physical Electronics and Circuit Models of Transistors , 1964 .

[8]  Raimo Sepponen,et al.  Use of junction temperature in control of CCT in luminaire , 2005 .

[9]  E. Fred Schubert,et al.  Light-Emitting Diodes , 2003 .

[10]  H. Rake,et al.  Step response and frequency response methods , 1980, Autom..

[11]  Bin-Juine Huang,et al.  Study of system dynamics model and control of a high-power LED lighting luminaire , 2007 .

[12]  Ian E. Ashdown.  Neural networks for LED color control , 2004, SPIE Optics + Photonics.

[13]  S. Muthu,et al.  Red, green and blue LED-based white light source: implementation challenges and control design , 2003, 38th IAS Annual Meeting on Conference Record of the Industry Applications Conference, 2003..

[14]  Michael S. Shur,et al.  Quadrichromatic white solid state lamp with digital feedback , 2004, SPIE Optics + Photonics.

[15]  P. T. Tsilingiris.  On the thermal time constant of structural walls , 2004 .

[16]  Bin-Juine Huang,et al.  Study of System Dynamics of High-Power LEDs , 2006, 2006 International Conference on Electronic Materials and Packaging.