# PFC Single-Phase AC/DC Boost Converters: Bridge, Semi-Bridgeless, and Bridgeless Topologies
## 5 Summary of PFC Single-Phase AC-DC Based on Topologies of a Boost Converter  
This section summarizes the BBC, SBBC, and BLBC converters categorized in this paper. It was found that most of the PFC Single-Phase AC-DC Boost converter topologies are used for applications in low (L) and medium (M) voltage and power; a classification concerning these aspects is included in this section. This section also includes recommendations to help designers and developers in the process of topology selection according to their specific requirements. Table 1 includes the summary in terms of control, voltage level, power level, number of semiconductors (SM), and number of inductors and capacitors (IC) that compose each topology. \begin{table}
\begin{tabular}{l c c c c c c c c} \hline \hline \multirow{2}{*}{**Converter**} & \multicolumn{2}{c}{**Category**} & \multicolumn{2}{c}{**Control**} & \multicolumn{2}{c}{**Voltage**} & \multicolumn{2}{c}{**Power**} & \multirow{2}{*}{**Semi-**} & \multirow{2}{*}{**Inductors+** Capacitors**} \\ \cline{2-2} \cline{5-6}  & **BBC** & **SBBC** & **BLBC** & **Linear** & **Non-Linear** & **L** & **M** & **L** & **M** \\ \hline Conventional & X & & X & X & X & X & 6 & 2 \\ Psudo continuous & X & & & X & X & X & 8 & 2 \\ Interleaved & X & & X & X & X & X & 8 & 3 \\ Hybrid interleaved & X & & X & X & Not recommended & 10 & 4 \\ Bidirectional & X & & & X & X & X & 6 & 3 \\ Bidirectional & X & & & X & Not recommended & 8 & 3 \\ flexible switches & & & & X & Not recommended & 8 & 3 \\ Bidirectional & X & & & X & Not recommended & 8 & 3 \\ interleaved & & & & & & & & \\ \hline Conventional & X & X & X & X & X & 4 & 2 \\ Soft switching & X & X & X & X & X & X & 6 & 5 \\ Isolation & X & X & X & X & X & 5 & 3 \\ Clamped Diodes & X & X & X & X & X & 6 & 3 \\ Clamped switches & X & X & X & X & X & 6 & 4 \\ Clamped diodes & X & & X & X & X & 8 & 3 \\ and switches & & & & X & X & & 4 & 5 \\ Clamped capacitors & X & X & X & X & X & 4 & 7 \\ coupling inductors & & & & & & & \\ Zero voltage transition & X & & & X & Not recommended & 11 & 5 \\ \hline Conventional & & X & X & X & X & X & 4 & 2 \\ Conventional GaN & & X & & X & X & X & X & 4 & 2 \\ Interleaved & X & X & X & & X & X & 6 & 5 \\ Interleaved GaN & & X & & X & X & X & 6 & 4 \\ Pseudo totem-pole & & X & & X & Not recommended & 6 & 3 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Summary and comparison among BBC, SBBC, and BLBC topologies categorized in this paper. Figure 17: Bridgeless boost converter pseudo totem-pole topology. Concerning control techniques, it was found that most topologies can reach a high power factor when a linear control technique is used; however, high values of \(THD_{i}\) and efficiency are difficult to obtain. Basically, to reach high standards of power quality, a robust EMI filter is required, which increases the cost. It was also found that, when nonlinear control techniques are implemented, all topologies present low \(THD_{i}\) (lower than 6%), high power factor (greater than 0.99) and high efficiency (greater than 97%). Then, it is concluded that, by using nonlinear control techniques, it is possible to obtain a high standard of power quality and at the same time reduce the cost of the converter; however, the implementation of a nonlinear control represents a greater effort in the development stage. BBC topologies with bidirectional switch are not recommended due to the fact that these topologies increase the number of switches; consequently, the converter cost is higher and the control technique is more difficult to develop. Moreover, a better performance in terms of dynamic response can be obtained by means of other BBC or SBBC topologies. SBBC with zero voltage transition is not recommended due to its large number of components, which make it expensive; BLBC pseudo totem-pole is not recommended since similar dynamic performance can be obtained with the conventional totem-pole topology.