Predictive Boundary Conduction Mode PFC Converter with Optimized Variable On-time Control for Driving LED Lighting

Abstract

This paper presents an optimized variable on-time (VOT) control for predictive boundary conduction mode (BCM) PFC converter to drive LED lighting applications. The constant on-time (COT) control is normally implemented in conventional predictive control methods, which in turn leads to high input current THD. Many VOT control methods have been proposed to reduce the input current THD. However, these VOT control methods are too complex to be implemented in the predictive control. An optimized VOT control method is applied for implementing the VOT control in predictive control in this paper. The optimized VOT control is very simple and takes a short calculation time in DSP. Thus, it can be successfully implemented in the predictive control. Experimental results demonstrate the input current THD is indeed improved in the optimized VOT control.