Illumination Balancing Algorithm for Smart Lights

In this paper, we present two decentralized algorithms that aim to achieve uniform lighting across the floor of an experimental testbed under a variety of challenges, including cross-illumination effects and external light disturbances. These challenges cause over-illuminations in the environment that result in a waste of energy and discomfort to the occupants. First, a decentralized integral control approach that does not have any communication between the lights is developed and applied to the system. Due to its failure in achieving uniform lighting when the cross-illumination effects are maximized, a new decentralized method called the illumination balancing algorithm (IBA) is developed that takes the local light levels into account when adjusting the light voltages. The stability analysis of the IBA for the full height partitions case of the testbed is shown as well as the regulation problem results where the algorithm successfully balances the illuminations and hence achieves uniform lighting. In order to track a desired light level across the zones, the IBA is augmented with an integral control at an arbitrarily selected control loop. This combined algorithm achieved successful control even in a case where the decentralized integral control failed.