An interior-points algorithm for color and CCT control of multichannel LED lighting system using a Smart 18-Channel Spectral Sensor

In this paper we provide a simple and cost-effective control scheme for controlling a colored light ambience or Correlated Color Temperature (CCT) in a room at least partially lit up by a set of colored LEDs. The objective is to maintain a desired lighting ambience or desired CCT in a room by taking into account external lighting (external disturbances) sources and/or rejecting disturbances specific to LEDs (spectral drift). This control system consists in using a Smart 18-Channel Spectral Sensor, a PI controller, an anti-windup system, an interior-point algorithm for nonlinear optimization and a set of colored LEDs. It provides improved performance and enables the management of various scenarios (reduce energy consumption, protect the retina of the eye, ...) based on the nonlinear optimization algorithm and on the preference of certain LEDs. The experimental results are given to illustrate the performance of the proposed algorithm.