## 3 Development of Prototype Models of the Smart Photovoltaic System Blind
### Properties 2: Tracking System  
#### 3.2.1 Tracker Types Installed in Prototype Models of the SPSB  
According to previous studies, the performance of the electricity generation of the PV system was enhanced in the order of the dual-axis tracker type, single-axis tracker type, and fixed type [19; 20; 21; 22]. To improve the performance of the electricity generation of the SPSB, the application of the tracker is required. Therefore, among the total five tracker types, four tracker types (i.e., fixed type, VSAT, HSAT, and AADAT) that can track the daily east-west motion and north-south motion of the sun were applied to the prototype model of the SPSB.  
The first prototype model applied the VSAT to track the north-south motion of the sun. In the second and third prototype models, the four tracker types (i.e., fixed type, VSAT, HSAT, and AADAT) that can track the daily east-west motion and north-south motion of the sun were all applied. Figure 4  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Classifications** & **First Prototype Model** & **Second Prototype Model** & **Third Prototype Model** \\ \hline PV panel & SP1-75 & 502500-16V & 502500-16V \\ Manufacturer & Solopower & Solar Center & Solar Center \\ Size of PV panel & 398 mm \(\times\) 2197 mm \(\times\) 2 mm & 250 mm \(\times\) 50 mm \(\times\) 2 mm & 250 mm \(\times\) 50 mm \(\times\) 2 mm \\ Maximum power (\(P_{\mathrm{max}}\)) & 75 W & 1.5 W & 1.5 W \\ Maximum power voltage (\(V_{\mathrm{mp}}\)) & 21.8 V & 16 V & 16 V \\ Optimum operating current (\(l_{\mathrm{mp}}\)) & 3.4 A & 95 mA & 95 mA \\ Short-circuit current (\(l_{\mathrm{sc}}\)) & 4.3 A & 99 mA & 99 mA \\ Open-circuit voltage (\(V_{\mathrm{oc}}\)) & 30.6 V & 19.4 V & 19.4 V \\ \hline \hline \end{tabular}
\end{table}
Table 4: Specifications of the PV panel by prototype model.  
shows the concept diagram of the third prototype model of the SPSB. All the PV panels on the blind slat are connected each other with lifting and rotating ropes. The prototype model of the SPSB moves along the north-south motion of the sun using the motor 'A', motor 'B', rotating rope, and wire-puller, whereas the prototype model of the SPSB moves along the east-west motion of the sun using motor 'C' and gears. Aforementioned in Section 2.2.1, the VSAT and HSAT can track the daily east-west motion (\(X\)-axis) and north-south motion (\(Y\)-axis) of the sun, respectively. In addition, the AADAT can track the daily east-west motion (\(X\)-axis) and north-south motion (\(Y\)-axis) of the sun. In particular, since the third prototype model is composed of four columns, a comparative analysis on the performance of the electricity generation of the SPSB can be conducted by applying the four tracker types (i.e., fixed type, VSAT, HSAT, and AADAT) at the same time.
* VSAT (vertical single-axis (X-axis) tracker): Track the daily east-west motion of the sun.
* HSAT (horizontal single-axis (Y-axis) tracker): Track the daily north-south motion of the sun.
* AADAT (azimuth-altitude dual-axis (X- and Y-axes) tracker): Track the daily east-west motion and daily north-south motion of the sun.