Ph.D. Dissertation A Study on Modulated Carrier Control Method for Power Factor Correction Boost Converter BY Jintae Kim
Interdisciplinary Program in
Photovoltaic System Engineering
The Graduate School
Sungkyunkwan University
Abstract
A Study on Modulated Carrier Control Method
For Power Factor Correction Boost Converter
As demand of electrical devices steeply increases, harmonic pollution on the power grid
has attracted concern. This circumstance leads standards such as IEC61000-3-2 and 80-Plus
regulating harmonic currents or PF (Power Factor) to have been more stringent. Thus, a PFC
(Power Factor Correction) circuit able to improve power quality while reducing current
harmonics has been indispensible at the electrical devices. For the reason, the PFC has been
constantly researched so that various topologies and control types have been proposed and
realized as silicon.
So far, many of proposed PFC converters have each optimal operation mode offering good
PFC performance such as CCM (Continuous Conduction Mode), DCM (Discontinuous
Conduction Mode) or BCM (Boundary Conduction Mode). The same is true of conventional
MCC (Modulated Carrier Control) PFC converters. The conventional MCC PFC method does
not require sensing the line input voltage and offers very fast dynamic current control by
directly comparing an inductor current. These are advantages of the conventional ones.
However, these conventional MCC converters enter into DCM by load reduction, the line
input current is distorted and harmonic current is increased.
In this dissertation, a research on new MCC method is revealed from a study and analysis
on the conventional MCC PFC converter. Two types of MCC method are proposed to
overcome the problem of the conventional MCC aforementioned. The proposed MCC
methods newly employ a circuit to detect DCM region and generate DCM compensation
signal in common. Using the compensation, the MCC methods can control the line input
current as a desirable sinusoidal waveform, which results in better PFC performance
regardless of a line input voltage range or load variation unlike the conventional MCC method.
With all them, the proposed method can maintain the advantages of the conventional MCC
method and even it can be easily implemented with analog or digital circuits.
This dissertation describes the proposed MCC methods and the operating principle. In
addition, to verify the proposed methods, they are implemented in 400 W PFC boost converter.
