Single-axis tracker PV layout creation

Learn how to configure and generate single-axis tracked PV layouts in PVcase GM. This step-by-step tutorial covers initial settings setup, custom frame preset creation, placement and shading controls, multi-area generation, and pile grouping analysis.

Single-axis tracker - PV layout creation

Before starting frame creation, you must set up the Layout generation settings. Click the Layout generation settings button and adjust the information there.

In the Layout generation settings menu, the following selections are available:

• Select Distance units (milimeters/meters or inches/feet).

• Define Distance precision (two, three or four decimals).

• Select Slope units (degrees, percentages).

• See the AutoCAD units for distance (and if necessary, correct to match the PVcase GM distance units).

• Select the Restriction zone layer(s) (inside of boundaries will be avoided during frame generation).

• The Optimized frames option hides the modules (shows only frame boundary) to increase the performance of AutoCAD.

• The Topographic layout option allows generating on a terrain survey, or on a flat surface when you don't have terrain data.

• Using the Select button you can select the terrain layers to be used.

• Change from Existing (original) topography to Proposed topography (after performing the grading).

The next necessary step before area generation is to set up the Frame & park settings. Click the Frame & park settings button and adjust the information in the tabs.

This includes the physical parameters of your frames, placement setup, park's settings, and reference height setup.

Frame creation

Using the Current preset field and adjacent icons, you can:

• Create new presets:

• Customize names for frame presets;

• Duplicate the current frame preset;

• Import and export preset configuration:

  

  For more information about importing and exporting settings: Import and export settings

   

• Create a preset based on a selected frame from the model space;

• Delete an existing preset;

The Module Parameters section allows you to define custom module dimensions and power to match those that are provided by your module manufacturer of choice.

The Frame parameters section allows us to specify:

• The framing type (fixed-tilt, single-axis tracker, or east-west); In our example, we will use a Single-axis tracker.

• Here we can also select the subtypes Multi-row trackers and Terrain following trackers and access the corresponding settings:
   

Check the following articles for more details on these:

Multi-row trackers

Terrain following trackers
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• The module orientation - either portrait or landscape.

• The grid size of the frame - we can specify the number of module rows and columns in our frame.

  

   

• You can also modify the horizontal and vertical gaps between modules.

  

   

• The motor gap size lets us adjust the motor gap. You can also choose not to use one by disabling the checkbox.

• You can configure the number of joint gaps and their size as needed.

• In the field Frame length, you can see the calculated length of our frame

  

   

• The frame power is determined by multiplying the power of the individual modules by the number of modules per frame.

Open the Custom Piling menu to adjust the piling information for the currently selected frame.

You can adjust the motor position and the number of modules between joints. The changes are shown in the image on the right.

In the Piles setup window, the first thing you can do is specify the Overhang, past both ends of the first and last modules:

Next, define the placement of piles based on three options that can be selected:

Each one supports a different configuration, but you always have the option to manually adjust the distances between the poles as needed by clicking the values. The changes are shown in the right-hand image.

For the Custom configuration option, you can check the Equal Margins box. This makes the distance from the ends of the frame to the closest pole the same.

For the Custom configuration option, we can also check the Mirror from the middle box. This mirrors the values you enter in the first half of the spacing table by auto-populating the second half to match.

Under Torque tube setup, define the turning angle range. It is also recommended, for better representation of the 3D geometry of the tracker to input the following:

• Torque tube diameter

• Torque tube top gap, from bottom of the module to top of torque tube

• Torque tube bottom gap, from top of the pile to bottom of the torque tube

With the torque tube configuration, you can represent trackers with concentric bearings in more detail, which have the widest market adoption so far.

Once satisfied with the piling options, click OK to finalize the process.

Placement setup

Now that you've explored PVcase's Frame Creation capabilities, take a look at the placement setup options. Start by opening the Placement Setup menu tab and selecting Single-axis trackers.

Here you can see the Preset Library field which contains all the presets we created just before for this specific DWG file. From here you can select which of the available presets we should use when creating new PV areas. You can select one or multiple presets that you would like to utilize, as long as they have matching row counts, vertical gap size, and tilt angles.

As with our example, you can see that we are not able to select one of the presets as it has different module lengths (different frame width).

You can also choose a specific color for each preset. To do so, click a color box, choose the color, and press OK to finalize.

Just below the Preset Library field, you can select the frame placement order.

For Single-axis trackers, only one option is available: Descending from the alignment line. This means that when populating the PV area, the software will place larger frames closest to the alignment line and keep smaller frames on the opposite side.

Park settings

After creating and selecting your frame presets, proceed to the Park settings options.

You can see two main sections: Inter-row settings and Corridor settings.

The inter-row settings allow you to define the Pitch, Inner spacing (East-West displacement of frames), and Row spacing (North-South displacement of frames).

If you change the Pitch value to 10m, the inner spacing will automatically be recalculated. Changing the inner spacing will consequently affect the pitch value - they are directly linked.

Additionally, Alignment type is an important feature that lets us specify how the frames will be organized.

Line will better utilize the available PV area to achieve maximum capacity, at the cost of alignment and an orderly design. This may be advantageous in smaller PV areas.

Grid and Motor will follow an orderly grid pattern. Grid uses the top of the frame as its reference point, while Motor uses the motor gap as its primary alignment reference.

Note: For the motor to work as intended, the number of modules on either side of the motor should match, and the size of the motor gaps or joint gaps between the presets should also match.

You are also able to set or draw azimuth for the trackers - up to 89.9°, although for single-axis trackers it is very unlikely to use an azimuth different than 0°.

Corridor settings, if enabled, let us space our frames in the PV area more efficiently and orderly, account for maintenance road clearances, and split the PV areas into a grid. You can also control the size of every second gap independently of the main vertical corridor gap, which provides even more flexibility.

Once you enable the Tracker corridors, you can edit the parameters, which will be illustrated and updated on the right-hand side of the window. Finally, you can also enable Corridor lines, which can be converted to roads if needed.

Note that Corridors are more commonly used when you select a Grid or Motor alignment type.

Height & Optimization

The Height & Optimization settings section allows us to define the reference frame height for the PV area we intend to generate.

When you open the tab, you will see there are two layout generation modes:

• Standard: this option will use the Frame reveal value on the edges of the axis line of the table, considering overhangs if they exist.

• Optimized: this option allows for a reference clearance range. The software starts by placing the frames at the lowest height, but if it encounters a collision anywhere in the frame, it increases the height and retests until no collision occurs. If collision is unavoidable, the frames will be placed at the maximum height. This means it is optimized for minimum cut, but at the expense of increasing the fill.

  

For more information about the optimized generation mode, visit Layout generation: optimized mode

Additionally, layouts that use tracking systems can have the torque tube enabled or disabled, and the values displayed for each scenario differ.

• Without torque tube enabled (Pile and Frame reveal are equal):

   

• With torque tube enabled (Pile and Frame reveal are different):

The difference between Pile and Frame reveal is shown in the following image:

(Pile reveal + Torque tube diameter + Top gap + Bottom gap) = Frame reveal

Please note that this is a reference value, not a minimum height. Enter the lowest frame height on flat terrain, rather than the minimum clearance height. PVcase positions frames based on the frame reveal height and does not account for mid-frame terrain collisions. However, these collisions can be analyzed later as part of the Civil analysis.

Area generation

The first step in generating areas is to define the PV area you will work in. In PVcase, define a PV area with a closed polyline. You can do this using the default AutoCAD polyline function. To create this, type PLINE and press Enter, then draw the desired perimeter of the PV area, ending the polyline at its starting point.

Once you have configured the Frame & Park settings and drawn your PV area boundary polylines, you can generate frames in one of two ways:

• Single area (one at a time)
• Multiple areas (simultaneously)

Generating a Single PV Area

1. Click the drop-down menu and select Generate single area.
2. Select your PV area boundary polyline, then press Space or Enter.
3. Draw an alignment line to define the frame orientation. You can place this line along, inside, or outside the perimeter (e.g., through the middle of the area).
4. Press Space or Enter to generate the frames.

Clearing a PV Area

To remove generated frames from a boundary:

1. Right-click the PV area perimeter polyline.
2. Go to the PVcase sub-menu and click Clear PV area.

Generating Multiple PV Areas

1. To populate several sections simultaneously:
2. Click the drop-down menu and select Generate multiple areas.
3. Select all target PV area polylines, then press Space or Enter.
4. Draw a single alignment line across the selected areas.
5. Press Space or Enter to generate frames across all selected areas.

Note: When generating multiple areas at once, all areas must share a single alignment line.

Generate with Capacity iteration - This mode allows to calculate different scenarios based on varying row spacing and tilt angle. Learn more in Capacity iteration

Show piling

Once the PV areas are generated, we can generate the piling. 

1. Click the Show piling button
2. Select the PV area perimeter line, and press Space or Enter.
3. Soon your frames will be populated with their piles.

To see what the piling looks like, we may choose an isometric view (SW Isometric, for example) and/or while holding the Shift key and Middle Mouse button to rotate the view manually using the mouse.

Pile grouping by length

This function allows us to see how many piles belong to each length group and how they're spatially distributed, allowing us to spot problematic areas in need of changes to either pile lengths or grading.

1. Run Show piling as described above.

2. Open the Pile grouping window from the same drop-down menu.

3. Define the start and end values of the length groups and the increments between each and customize group colors:

4. Select PVarea(s) and run Group piles - this will color each pile according to its length group and populate the pile count in the table:

5. Export to CAD model space.

6. Export to the BOM Excel sheet:

Moving frames manually (shadow frames)

After generation, you can freely move tables around and copy them. However, if the layout is terrain-based, they will turn red (and move to the PVcase Shadow Frames layer) because they need to be adapted to the terrain or reassigned to an area. Until they are resolved they will not be counted inside the Layout information.

Learn more about how to work with shadow frames in Shadow frames.