Controlling the correlated color temperature of high CRI light-emitting diodes in response to the time of day as a way of enhancing the well-being of smart city residents

In order to meet people's biological and emotional requirements, this study provides a novel approach for controlling the correlated color temperature (CCT) of light-emitting diodes (LEDs) with high color rendering index (CRI) according to the individual's circadian rhythm and the time of day. The suggested technique regulates the correlated color temperature of high CRI LEDs, considering the time of day, analogous to the function of natural light from sunrise to sunset. This study establishes a mathematical model for determining the relationship between the CCT of LED light sources and the time of day. Then, using the introduced model, control of the correlated color temperature of light-emitting-diodes is performed. The introduced method is based on employing two channels with 2700 K and 6500 K LEDs and blending their light colors. Simulation results confirm the precision of the proposed approach. This system can be used in indoor locations such as commercial settings, educational environments, health care facilities, and so on, especially places where due to the long-term presence of people, the effects of artificial lighting on the performance and efficiency of inhabitants are significant. This method is recommended for improving residents' well-being, particularly in smart cities.