Abstract

This paper describes a new design concept of automatically diagnosing and compensating LED degradations in distributed solid state lighting (SSL) systems. A failed LED may significantly reduce the overall illumination level, and destroy the uniform illumination distribution achieved by a nominal system. To our knowledge, an automatic scheme to compensate LED degradations has not yet been seen in the literature, which requires a diagnostic step followed by control reconfigurations. The main challenge in diagnosing LED degradations lies in the usually unsatisfactory observability in a distributed SSL system, because the LED light output is usually not individually measured. In this work, we tackle this difficulty by using pulse width modulated (PWM) drive currents with a unique fundamental frequency assigned to each LED. Signal processing methods are applied in estimating the individual illumination flux of each LED. Statistical tests are developed to diagnose the degradation of LEDs. Duty cycle of the drive current signal to each LED is re-optimized once a fault is detected, in order to compensate the destruction of the uniform illumination pattern by the failed LED.

© 2011 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. E. Schubert, J. Kim, H. Luo, and J. Xi, “Solid-state lighting a benevolent technology,” Rep. Prog. Phys. 69, 3069–3099 (2006).
    [CrossRef]
  2. I. Ashdown, “Solid-state lighting design requires a system-level approach,” in “SPIE Newsroom,” (2006). http://newsroom.spie.org/x2235.xml?highlight=x531
    [CrossRef]
  3. N. Narendran, N. Maliyagoda, A. Bierman, R. Pysar, and M. Overington, “Characterizing white LEDs for general illumination applications,” Proc. SPIE 3938, 240–248 (2000).
    [CrossRef]
  4. C. Tsuei, J. Pen, and W. Sun, “Simulating the illuminance and the efficiency of the LED and fluorescent lights used in indoor lighting design,” Opt. Express 16, 18692–18701 (2008).
    [CrossRef]
  5. I. Moreno, and U. Contreras, “Color distribution from multicolor LED arrays,” Opt. Express 15, 3607–3618 (2007).
    [CrossRef] [PubMed]
  6. Z. Qin, K. Wang, F. Chen, X. Luo, and S. Liu, “Analysis of condition for uniform lighting generated by array of light emitting diodes with large view angle,” Opt. Express 18, 17460–17476 (2010).
    [CrossRef] [PubMed]
  7. C. Sun, W. Chien, I. Moreno, C. Hsieh, and Y. Lo, “Analysis of the far-field region of LEDs,” Opt. Express 17, 313918 (2009).
    [CrossRef]
  8. Y. Ding, X. Liu, Z. Zheng, and P. Gu, “Freeform LED lens for uniform illumination,” Opt. Express 16, 12958–12966 (2008).
    [CrossRef] [PubMed]
  9. M. Blanke, M. Kinnaert, J. Lunze, and M. Staroswiecki, Diagnosis and Fault-Tolerant Control (Springer Verlag, Heidelberg, 2003).
  10. T. Shen, A. Lau, and C. Yu, “Simultaneous and independent multi-parameter monitoring with fault localization for DSP-based coherent communication systems,” Opt. Express 18, 23608–23619 (2010).
    [CrossRef] [PubMed]
  11. H. Yang, J. Bergmans, and T. Schenk, “Illumination sensing in LED lighting systems based on frequency-division multiplexing,” IEEE Trans. Signal Process. 57, 4269–4281 (2009).
    [CrossRef]
  12. H. Yang, J. Bergmans, T. Schenk, J. Linnartz, and R. Rietman, “An analytical model for the illuminance distribution of a power LED,” Opt. Express 16, 21641–21646 (2008).
    [CrossRef] [PubMed]
  13. A. Descombes, and W. Guggenbuhl, “Large signal circuit model for LEDs used in optical communication,” IEEE Trans. Electron. Dev. 28, 395–404 (1981).
    [CrossRef]
  14. D. Wood, Optoelectronic Semiconductor Devices (Prentice Hall, 1994).
  15. L. Ljung, System Identification - Theory for the User (Prentice Hall, 1987).
  16. F. Gustafsson, Adaptive filtering and change detection (John Wiley & Sons, 2001).
    [CrossRef]
  17. K. Åström, and B. Wittenmark, Computer controlled systems: theory and design (Prentice Hall, 1984).
  18. IEC 62386, Digital addressable lighting interface (2007).
  19. S. Boyd, and L. Vandenberghe, Convex Optimization (Cambridge University Press, 2004).
  20. Philips Lumileds, “LUXEON Rebel Illumination Portfolio - Technical Datasheet DS63,” http://www.philipslumileds.com/pdfs/DS63.pdf.

2010

2009

C. Sun, W. Chien, I. Moreno, C. Hsieh, and Y. Lo, “Analysis of the far-field region of LEDs,” Opt. Express 17, 313918 (2009).
[CrossRef]

H. Yang, J. Bergmans, and T. Schenk, “Illumination sensing in LED lighting systems based on frequency-division multiplexing,” IEEE Trans. Signal Process. 57, 4269–4281 (2009).
[CrossRef]

2008

2007

2006

E. Schubert, J. Kim, H. Luo, and J. Xi, “Solid-state lighting a benevolent technology,” Rep. Prog. Phys. 69, 3069–3099 (2006).
[CrossRef]

2000

N. Narendran, N. Maliyagoda, A. Bierman, R. Pysar, and M. Overington, “Characterizing white LEDs for general illumination applications,” Proc. SPIE 3938, 240–248 (2000).
[CrossRef]

1981

A. Descombes, and W. Guggenbuhl, “Large signal circuit model for LEDs used in optical communication,” IEEE Trans. Electron. Dev. 28, 395–404 (1981).
[CrossRef]

Bergmans, J.

H. Yang, J. Bergmans, and T. Schenk, “Illumination sensing in LED lighting systems based on frequency-division multiplexing,” IEEE Trans. Signal Process. 57, 4269–4281 (2009).
[CrossRef]

H. Yang, J. Bergmans, T. Schenk, J. Linnartz, and R. Rietman, “An analytical model for the illuminance distribution of a power LED,” Opt. Express 16, 21641–21646 (2008).
[CrossRef] [PubMed]

Bierman, A.

N. Narendran, N. Maliyagoda, A. Bierman, R. Pysar, and M. Overington, “Characterizing white LEDs for general illumination applications,” Proc. SPIE 3938, 240–248 (2000).
[CrossRef]

Chen, F.

Chien, W.

C. Sun, W. Chien, I. Moreno, C. Hsieh, and Y. Lo, “Analysis of the far-field region of LEDs,” Opt. Express 17, 313918 (2009).
[CrossRef]

Contreras, U.

Descombes, A.

A. Descombes, and W. Guggenbuhl, “Large signal circuit model for LEDs used in optical communication,” IEEE Trans. Electron. Dev. 28, 395–404 (1981).
[CrossRef]

Ding, Y.

Gu, P.

Guggenbuhl, W.

A. Descombes, and W. Guggenbuhl, “Large signal circuit model for LEDs used in optical communication,” IEEE Trans. Electron. Dev. 28, 395–404 (1981).
[CrossRef]

Hsieh, C.

C. Sun, W. Chien, I. Moreno, C. Hsieh, and Y. Lo, “Analysis of the far-field region of LEDs,” Opt. Express 17, 313918 (2009).
[CrossRef]

Kim, J.

E. Schubert, J. Kim, H. Luo, and J. Xi, “Solid-state lighting a benevolent technology,” Rep. Prog. Phys. 69, 3069–3099 (2006).
[CrossRef]

Lau, A.

Linnartz, J.

Liu, S.

Liu, X.

Lo, Y.

C. Sun, W. Chien, I. Moreno, C. Hsieh, and Y. Lo, “Analysis of the far-field region of LEDs,” Opt. Express 17, 313918 (2009).
[CrossRef]

Luo, H.

E. Schubert, J. Kim, H. Luo, and J. Xi, “Solid-state lighting a benevolent technology,” Rep. Prog. Phys. 69, 3069–3099 (2006).
[CrossRef]

Luo, X.

Maliyagoda, N.

N. Narendran, N. Maliyagoda, A. Bierman, R. Pysar, and M. Overington, “Characterizing white LEDs for general illumination applications,” Proc. SPIE 3938, 240–248 (2000).
[CrossRef]

Moreno, I.

C. Sun, W. Chien, I. Moreno, C. Hsieh, and Y. Lo, “Analysis of the far-field region of LEDs,” Opt. Express 17, 313918 (2009).
[CrossRef]

I. Moreno, and U. Contreras, “Color distribution from multicolor LED arrays,” Opt. Express 15, 3607–3618 (2007).
[CrossRef] [PubMed]

Narendran, N.

N. Narendran, N. Maliyagoda, A. Bierman, R. Pysar, and M. Overington, “Characterizing white LEDs for general illumination applications,” Proc. SPIE 3938, 240–248 (2000).
[CrossRef]

Overington, M.

N. Narendran, N. Maliyagoda, A. Bierman, R. Pysar, and M. Overington, “Characterizing white LEDs for general illumination applications,” Proc. SPIE 3938, 240–248 (2000).
[CrossRef]

Pen, J.

Pysar, R.

N. Narendran, N. Maliyagoda, A. Bierman, R. Pysar, and M. Overington, “Characterizing white LEDs for general illumination applications,” Proc. SPIE 3938, 240–248 (2000).
[CrossRef]

Qin, Z.

Rietman, R.

Schenk, T.

H. Yang, J. Bergmans, and T. Schenk, “Illumination sensing in LED lighting systems based on frequency-division multiplexing,” IEEE Trans. Signal Process. 57, 4269–4281 (2009).
[CrossRef]

H. Yang, J. Bergmans, T. Schenk, J. Linnartz, and R. Rietman, “An analytical model for the illuminance distribution of a power LED,” Opt. Express 16, 21641–21646 (2008).
[CrossRef] [PubMed]

Schubert, E.

E. Schubert, J. Kim, H. Luo, and J. Xi, “Solid-state lighting a benevolent technology,” Rep. Prog. Phys. 69, 3069–3099 (2006).
[CrossRef]

Shen, T.

Sun, C.

C. Sun, W. Chien, I. Moreno, C. Hsieh, and Y. Lo, “Analysis of the far-field region of LEDs,” Opt. Express 17, 313918 (2009).
[CrossRef]

Sun, W.

Tsuei, C.

Wang, K.

Xi, J.

E. Schubert, J. Kim, H. Luo, and J. Xi, “Solid-state lighting a benevolent technology,” Rep. Prog. Phys. 69, 3069–3099 (2006).
[CrossRef]

Yang, H.

H. Yang, J. Bergmans, and T. Schenk, “Illumination sensing in LED lighting systems based on frequency-division multiplexing,” IEEE Trans. Signal Process. 57, 4269–4281 (2009).
[CrossRef]

H. Yang, J. Bergmans, T. Schenk, J. Linnartz, and R. Rietman, “An analytical model for the illuminance distribution of a power LED,” Opt. Express 16, 21641–21646 (2008).
[CrossRef] [PubMed]

Yu, C.

Zheng, Z.

IEEE Trans. Electron. Dev.

A. Descombes, and W. Guggenbuhl, “Large signal circuit model for LEDs used in optical communication,” IEEE Trans. Electron. Dev. 28, 395–404 (1981).
[CrossRef]

IEEE Trans. Signal Process.

H. Yang, J. Bergmans, and T. Schenk, “Illumination sensing in LED lighting systems based on frequency-division multiplexing,” IEEE Trans. Signal Process. 57, 4269–4281 (2009).
[CrossRef]

Opt. Express

Proc. SPIE

N. Narendran, N. Maliyagoda, A. Bierman, R. Pysar, and M. Overington, “Characterizing white LEDs for general illumination applications,” Proc. SPIE 3938, 240–248 (2000).
[CrossRef]

Rep. Prog. Phys.

E. Schubert, J. Kim, H. Luo, and J. Xi, “Solid-state lighting a benevolent technology,” Rep. Prog. Phys. 69, 3069–3099 (2006).
[CrossRef]

Other

I. Ashdown, “Solid-state lighting design requires a system-level approach,” in “SPIE Newsroom,” (2006). http://newsroom.spie.org/x2235.xml?highlight=x531
[CrossRef]

M. Blanke, M. Kinnaert, J. Lunze, and M. Staroswiecki, Diagnosis and Fault-Tolerant Control (Springer Verlag, Heidelberg, 2003).

D. Wood, Optoelectronic Semiconductor Devices (Prentice Hall, 1994).

L. Ljung, System Identification - Theory for the User (Prentice Hall, 1987).

F. Gustafsson, Adaptive filtering and change detection (John Wiley & Sons, 2001).
[CrossRef]

K. Åström, and B. Wittenmark, Computer controlled systems: theory and design (Prentice Hall, 1984).

IEC 62386, Digital addressable lighting interface (2007).

S. Boyd, and L. Vandenberghe, Convex Optimization (Cambridge University Press, 2004).

Philips Lumileds, “LUXEON Rebel Illumination Portfolio - Technical Datasheet DS63,” http://www.philipslumileds.com/pdfs/DS63.pdf.

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (10)

Fig. 1
Fig. 1

Geometry between an LED and a target. Circles: target points.

Fig. 2
Fig. 2

An nl × nw LED array on a flat surface with equal spacing s0.

Fig. 3
Fig. 3

FDM-PWM light pulses.

Fig. 4
Fig. 4

Filter bank for illumination sensing using FDM-PWM drive current signals with a unique fundamental frequency to each LED.

Fig. 5
Fig. 5

Scheme of fault tolerant control of a SSL system.

Fig. 6
Fig. 6

Contributions of the LEDs to the photosensor. (a). Spatial pattern. (b). SNRs.

Fig. 7
Fig. 7

Illumination distribution (lumen/m2) of the LED array with a degraded LED in the center. (a). Overall spatial distribution. (b). Distribution along the line of −0.5 ≤ x ≤ 0.5,y ≤ 0.

Fig. 8
Fig. 8

Test statistics for diagnosing LED degradations. Dash-dotted purple: time instant of the fault onset. Dash-dotted cyan: 0.0405sec intervals respectively from the start and from the fault onset.

Fig. 9
Fig. 9

Reconfigured illumination distribution (lumen/m2) of the LED array with a degraded LED in the center. (a). Overall spatial distribution. (b). Distribution along the line of −0.5 ≤ x ≤ 0.5,y = 0.

Fig. 10
Fig. 10

Reconfigured duty cycles of LED currents. (a). All LEDs. (b). Zoom into the neighborhood of the failed LED. Dots: positions of the LEDs projected onto the target surface. Red square: magnitude of the original duty cycle, pi = 0.4, ∀i. Circles with different levels of red: magnitudes of duty cycles. The darker the circles than the square, the longer their duty cycles than 0.4; and vice versa. The color is calculated as 1 – pi · [0 1 1], ∀i.

Equations (23)

Equations on this page are rendered with MathJax. Learn more.

( d , h ) = ( μ + 1 ) 0 2 π h 2 ( 1 + d 2 h 2 ) μ + 3 2 .
q i ( t ) = { 0 , t p i 2 f i 1 e t + p i 2 f i τ on , i , p i 2 f i t p i 2 f i ( 1 e p i f i τ on , i ) e t + p i 2 f i τ off , i , t p i 2 f i .
rect ( t ) = { 1 , 1 2 t 1 2 0 , otherwise .
I x , y , h ( t ) = i = 1 L n = a f , i q i ( t n f i ) + e ( t ) .
a ^ f , i ( t ) = π sin ( π p i ) | 0 T I x , y , h ( t τ ) g ( τ ) e j 2 π f i τ d τ | .
g ( t ) = 1 T rect ( t T 1 2 ) ,
| a ^ f , i ( t ) a ^ f , i ( t ) | | v i ( t ) | ,
P e g 2 ( t ) d t = P e T ,
0 , i ( t ) = η i c i ( t ) .
a f , i ( t ) = η i c i ( t ) α i μ i + 1 2 π h 2 ( 1 + d i 2 h 2 ) μ i + 3 2 ψ i ( t ) .
r i ( t ) = a f , i ( t ) a ^ f , i ( t ) ,
r i ( t ) = φ i ( t ) + w i ( t ) .
φ i ( t ) = η i ψ i ( t ) η i ψ i ( t ) = ( 1 δ ) η i ψ i ( t ) .
| a f , i ( t ) a ^ f , i ( t ) P e / T | | v i ( t ) P e / T | [ a f , i ( t ) a ^ f , i ( t ) ] 2 P e / T v i 2 ( t ) P e / T .
ζ i ( t ) no fault faulty γ χ 1 2 , β
SNR i = a f , i 2 ( t ) P e / T > γ χ 1 2 , β ;
x , y , h = i = 1 L p i η i c i α i μ i + 1 2 π h 2 ( 1 + d i 2 h 2 ) μ i + 3 2 .
( x , y ) TS ( x , y , h x , y , h ) 2 .
𝒥 = ( x , y ) TS w ( x , y ) ( x , y , h x , y , h ) 2 + i I all \ I fail w p i p i 2 .
min { p i | i I all \ I fail } 𝒥 s . t . 0.001 p i 0.97307 , i I all \ I fail .
i I an 0.97307 η i c i α i μ i + 1 2 π h 2 ( 1 + d i 2 h 2 ) μ i + 3 2 i I a n I fail p i η i c i α i μ i + 1 2 π h 2 ( 1 + d i 2 h 2 ) μ i + 3 2 ;
0.97 ( 1 a f , i a f , max [ 1 1 1 ] ) , i = 1 , , 81 ,
1 N d p 1 x , y 1 ( x , y , h ¯ ) 2 , where ¯ = 1 N d p 1 x , y 1 x , y , h ,

Metrics