A Digital Peak Current-Mode Control PFC with Bifurcation Control

A boost power factor correction (PFC) in continuous conduction mode (CCM) by the digital peak current-mode control method with bifurcation control is discussed in this paper. The proposed method is used to prevent the inductor current bifurcation behavior, which is caused by sub-harmonic oscillation when the duty cycle is upon to 50 percent. The bifurcation behavior will increase the inductor current ripple and dissipation, then reduce the Power Factor (PF). Different from the ramp compensation signal performed with analog IC in some papers, a MCU is used to be the controller and also provides the digital compensation function in this paper. With the timer, ADC, PWM, and comparator which are built in the MCU, the necessary parameters will be measured without extra components and additional cost. The proposed method is based on those parameters. In this paper, the MATLAB/Simulink simulation results show the proposed method workable.