## 5 Experimental Results  
Figure 7 shows a prototype of a 100 W TSBB converter fabricated to verify the improved power efficiency. The Arduino controller generates a 5 V pulse width modulation (PWM) to control the MOSFET driver IC input; upon receiving this signal, the MOSFET driver IC converts it to an 18 V drive signal and transfers it to the gate of the MOSFET. The specifications of the components are 20% or more larger than the calculated maximum stress considering the various input/output conditions of the experiment. Table 7 summarizes the detailed specifications of the components; Table 8 presents the maximum values of the voltage stress measured in the CV/CC modes.  
The experiments are conducted in the CV/CC modes of the three topologies. The experiment for the buck-boost topology is conducted separately for the step-down and step-up sections. In the CV mode, the power efficiency is measured for the output power range of 10-80 W at the switching frequency \(f_{\text{sw}}\) = 100 kHz of the output current. The  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Component** & **Part Name** & **Specification** \\ \hline PWM Generator & Arduino Nano & 5 V, 16 MHz \\ \hline \multirow{4}{*}{MOSFET Driver} & \multirow{4}{*}{HCPL-J312} & Output Peak Current = 2.5 A, Input Current = 7–16 mA \\  & & Supply Voltage = 15–30 V, Input Capacitance = 60 pF \\  & & Rise Time = 0.1 us, Fall Time = 0.1 us \\ \hline \multirow{4}{*}{MOSFET} & \multirow{4}{*}{RCX510N25} & Drain-Source Voltage V\({}_{\text{DSS}}\) = 250 V \\  & & Gate-Source Voltage V\({}_{\text{GSS}}\) = \(\pm\)30 V \\  & & Drain Current I\({}_{\text{D}}\) = 51 A \\  & & Static Drain-Source ON-State Resistance = 48 m\(\Omega\) \\  & & Output Capacitance = 350 pF \\  & & Rise Time = 300 ns, Fall Time = 210 ns \\ \hline \multirow{4}{*}{Diode} & \multirow{4}{*}{RF2001T3D} & Reverse voltage (DC) V\({}_{\text{R}}\) = 300 V \\  & & Forward voltage V\({}_{\text{F}}\) = 13 V (4 I\({}_{\text{F}}\) = 10 A) \\ \cline{1-1}  & & Average Rectified Forward Current I\({}_{\text{F}}\) = 20 A \\ \cline{1-1}  & & Reverse recovery time t\({}_{\text{sr}}\) = 25 ns (at I\({}_{\text{F}}\) = 0.5 A, I\({}_{\text{R}}\) = 1 A, I\({}_{\text{rr}}\) = 0.25 \(\times\) I\({}_{\text{R}}\)) \\ \hline \multirow{4}{*}{Inductor} & \multirow{4}{*}{CH270125} & Cross Section = 0.654 cm\({}^{2}\), Path Length = 6.35 cm \\  & & Window Area = 1.56 cm\({}^{2}\), Volume = 4.154 cm\({}^{3}\) \\ \cline{1-1}  & & AL Value = 157 nH/Turm\({}^{2}\), Permeability \(\mu\) = 125 \\ \cline{1-1}  & & Inductance = 250 uH \\ \hline \multirow{4}{*}{Electrolytic Capacitor} & \multirow{4}{*}{100 YXG820 MEFC18 \(\times\) 40} & Rated Voltage (V\({}_{\text{dc}}\)) = 100 V \\ \cline{1-1}  & & Rated ripple current = 2330 mA (at 100 kHz) \\ \cline{1-1}  & & Leakage Current = 3 uA, Impedance = 20 \({}^{\circ}\)C, 100 kHz \\ \cline{1-1}  & & Dissipation Factor(MAX) tan\(\delta\) = 0.08 \\ \cline{1-1}  & & Capacitance = 820 uF \\ \hline \hline \end{tabular}
\end{table}
Table 7: Components specifications.  
Figure 7: 100 W TSBB prototype.  
power efficiency was measured at three duty ratios to analyze the power efficiency based on the change in the duty ratio. If the input/output voltage variation ratio \(V_{var}\) is defined as the ratio of the difference between the input and output voltages to the input voltage, it can be expressed using the input voltage \(V_{i}\) and the output voltage \(V_{o}\) as:  
\[V_{var}\ (\%)=\frac{|V_{i}-V_{o}|}{V_{i}}\times 100 \tag{30}\]  
In each topology, the power efficiency was measured at the duty ratios where \(V_{var}\) was 25%, 33%, and 50%. Table 9 shows the duty ratio based on \(V_{var}\) in each topology. Figure 8a-d shows PWM waveforms of the conventional and the proposed TSBB converter in each topology implemented using Arduino Nano. Figure 8e-h presents waveforms of the inductor current, the gate-source voltage, and the output voltage of the conventional and proposed TSBB converters measured in CC mode at \(V_{var}\) = 33% (\(V_{o}\cong\)40 V).