Optimizing Energy Consumption for Lighting Control System via Multivariate Extremum Seeking Control With Diminishing Dither Signal

Abstract

Because that the light-energy consumption (LC) is growing quite dramatically over the past decades, the light-energy efficiency is regarded as a key component of the modern energy system in major cities. In this paper, a novel and sophisticated algorism of lighting control is presented to improve light-energy efficiency and cut down energy consumption, when considering the lighting system with multilighting equipment. In this paper, a multivariate extremum seeking controller is used to manipulate, respectively, the luminance of multilighting equipment, in order to track the minimal LC efficiently. Meanwhile, a proportional–integral–differential (PID) approach is adopted to achieve the required level of illumination. The proposed extremum seeking control (ESC) is designed to ensure the amplitude of the dither signal converge exponentially to zero, by making the amplitudes change with the extremum estimation error. The presented frame helps to improve search speed for the minimal LC value and remove the steady-state oscillations. The comparative experiments reveal that, compared with the convergence velocity of the Newton- and gradient-based ESCs, the developed method for the track of the minimal LC can have higher accuracy and faster speed. Note to Practitioners —In a modern large commercial building, the exorbitant LC is an important problem for the engineering technicians and managers, and the hybrid lighting system which combines artificial light with natural light offers a solution to this problem. However, the minimum light-energy optimal control is a very key problem in manipulating multigroup lighting equipment, since the required level of illumination usually varies according to the exterior lighting environment. This paper contributes to a useful multivariate extremum seeking controller to solve these light-energy control problems for multiple-input single-output hybrid lighting system, whereas the PID controller is also designed to maintain the required level of illumination simultaneously. This paper discusses how to seek the minimal energy necessary for the required levels of illumination by separately regulating different light equipment. The research results of this paper will be beneficial for a practical application of extremum seeking control method in enhancing the lighting energy efficiency of lighting system.