Mountain photovoltaic power plants are different from large-scale ground power plants in the desert. The mountainous terrain is complex and irregular, and the irregular mountain has a great influence on the layout of photovoltaic modules. Even if the designer gets the contour map of the mountain, he will be unable to start. Because it is difficult for designers to use contour maps to accurately analyze the shadow effects of mountains and components, and components and components at different times. Therefore, calculation assistance software must be used for analysis and design in the refined design of mountain photovoltaic projects.
At present, the commonly used mountain photovoltaic 3D design software are advanced application plug-ins based on a certain mature software. For example, Helios3D is a plugin based on Civil3D, Bochao PDP is a plugin based on AUTOCAD, and CANDELA3D is a plugin based on Sketch Up.
Since Sketch Up (Sketch Master) is widely used in China, and the interface is intuitive and easy to use, the following analysis will be carried out with Sketch Up's mountain photovoltaic analysis plug-in.
The first step: Import the contour map. Input the processed flat contour topographic map into Sketch Up to generate the corresponding 3D mountain contour topographic map. Figure 1 3D mountain contour topographic map generated by the sketch master. At this time, the designer can have a more intuitive understanding of the topography of the design object on the software interface. In order to be more intuitive and true, the contour map will be transformed into the surface of the mountain in the next step.
Figure 1 Mountain topographic map generated by Sketch Master
Step 2: Analyze the mountain. ① The north-facing mountains need to be selected and eliminated. ② Eliminate areas where things are oriented and cannot be arranged. ③ Eliminate areas with larger slopes according to construction difficulty. Get the mountain analysis diagram in Figure 3
Figure 2 Mountain analysis diagram
Step 3: Conduct sunlight analysis on the area suitable for component placement. For example, shadow analysis is performed according to the rule of no occlusion from 9:00-15:00 on the winter solstice. Remove the mountainous areas that do not meet the conditions again. As shown in Figure 4, the ocher part represents the appropriate part, while the gray part is the opposite.
Figure 3 Secondary analysis of the mountain
The fourth step: assist in analyzing the layout spacing. At this time, the mountain has been "analyzed" into many triangles, and the software will analyze and calculate each "triangle" according to the preset size and inclination of the square array to be arranged to obtain a suitable arrangement spacing. The analysis of the triangle surface and some other analysis calculations by the software are particularly large. The more complex the mountain, the higher the computer configuration requirements. It is recommended to use a computer with a separate graphics card, and 16G memory is recommended.
Figure 4 Mountains analyzed by software
Step 4: Partition and layout of components. The software will mark the triangle surface in various colors, and can automatically divide the area, and the designer can also manually divide the area. The terrain area is shown in Figure 5. Each irregular figure framed by the thick red line is an area with similar physical quantities. The designer can reduce the division accuracy and the number of graphics by adjusting the relevant parameters.
Figure 5 Schematic diagram of terrain division
Before arranging the components, you need to set the layout of the component array: the number of rows and columns, vertical or horizontal layout, inclination, azimuth and other design parameters. The system will arrange the components in an optimal way. Figure 6 Component array layout
The electrical designer can consider the location and wiring scheme of the component array to connect to the combiner box, inverter, and box transformer according to the "thick red line diagram" of the partition (the angle and slope are consistent) combined with the layout diagram of the component arrangement. I won’t go into details here.
Figure 6 Layout of component array
Summary: The use of software for auxiliary design allows designers to design in a targeted manner. Survey personnel can optimize the drawings on the spot with the design sketches, re-measure and adjust the layout,greatly improving efficiency and design accuracy.