Low-cost active power factor correction for single phase switching mode power supply

In this study, active power factor correction (PFC) solution designed without any integrated circuit (IC) for instead of the IC-active-PFC solution of the PFC part of the one or multi-output single phase switching mode power supply (SMPS) and so that the line current in phase with the line voltage. Also PFC makes its waveform sinusoidal. To achieve active PFC, current designs and application notes of the PFC IC producer companies were examined and the results of the constant Duty cycle triggering were analysed by using the Pspice simulation program. Additionally, the discontinuous conduction mode (DCM) triggering is done by transistor RC phase shift oscillator and the solution is simulated with Pspice program. The simulated constant Duty cycle and the transistor RC phase shift oscillator circuits are assembled on the printed circuit board (PCB). The results of the simulation were compared with the results of the boards. Experimental results are compared with the active PFC IC solution and the compliance with the related regulations of the designed active PFC solution is examined. This study, independently from the design topology of the SMPS, is a cost-down study and within the international regulation IEC 61000-3-2. The experimental results of the DCM Boost Converter are; 0.959 power factor (PF), 30.28% total harmonic distortion (THD), 75W output power, 400V DC output voltage and 92.09% efficiency. Although the academically studies for constant Duty Cycle triggering also exist, transistor RC phase shift oscillator have not been used as a constant Duty cycle generator (triggering Mosfet which is a component of PFC part) yet.