Fuzzy Logic Control With an Improved Algorithm for Integrated LED Drivers

Abstract

This paper presents a fast fuzzy logic control algorithm for a Takagi–Sugeno–Kang fuzzy controller, which is applied to integrated ${\text{LED}}$ drivers with the purpose of getting a good dynamic response and the reduction in the low-frequency (120 Hz) ripple. The algorithm uses the high-speed mathematical engine of a digital signal controller ${\text{(DSC)}}$ that is capable to achieve fast multiplications during a common one-cycle instruction. Therefore, the execution time of the controller is improved with the use of a ${\text{DSC}}$ . A scaling procedure is included in the program in order to use and to improve the accuracy of the multiplications and divisions in the ${\text{DSC}}$ mathematical engine. A low-range ${\text{DSC}}$ was used to program the proposed controller; therefore, the cost is affordable for ${\text{LED}}$ driver applications. The fuzzy control curve was approximated to the sliding mode control ${\text{(SMC)}}$ curve with the purpose of getting some of the good advantages of the ${\text{SMC}}$ strategy like a good dynamic performance. The proposed controller is used to regulate the ${\text{LED}}$ current. Simulation and experimental results are shown