Optimizing LED Driver Performance: Fuzzy PI Controller for Peak-to-Average Reduction in Output Current

Abstract

This paper presents an optimal gain-scheduling fuzzy PI controller applied to an ACDC
discontinuous conduction mode (DCM) flyback converter to achieve a high performance
electrolytic capacitor-less LED driver with high efficiency and high power factor. The proposed
system consists of seven PI controllers for seven different load currents which are designed
based on Particle Swarm Optimization (PSO) algorithm. By using the obtained data, a fuzzy
system is trained to give suitable PI gains for any load condition. Employing the proposed
controller significantly improves the peak-to-average ratio of the output current to 1.05 while the
LED driver reaches to a high power factor of 90.8% and its input current THD is equal to
11.88% meeting the IEC 61000-3-2 class C standard. Keywords—flyback converter; electrolytic
capacitor; fuzzy PI controller; PSO algorithm; peak-to-average ratio; THD; power factor.