Summary
This paper presents two complementary algorithms — simulated annealing for spectral matching and PID closed-loop feedback control — enabling multi-channel LED systems to generate and maintain arbitrary spectral power distributions with high accuracy despite temperature and aging drift. For circadian and human-centric lighting designers, this provides a practical engineering framework to reliably deliver and sustain target spectra (e.g., specific melanopic content) in real-world installations.
Key Findings
- Simulated annealing algorithm achieves spectral matching with color shifts Δu'v' < 5×10⁻⁴, within milliseconds computation time
- Closed-loop PID feedback control successfully compensates for spectral drift caused by LED temperature changes and lumen decay
- Combining both methods (using simulated annealing output as initial guess for PID) yields the best balance of speed, accuracy, and precision for embedded microprocessor implementation
Categories
The Science of Light: Develops algorithms for precise spectral power distribution matching in multi-channel LED systems, directly relevant to melanopic EDI control and lighting standards compliance.
Author(s)
A Llenas, J Carreras
Publication Year
2019
Number of Citations
24
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