Design rule purpose
The purpose of this design rule is to allow the user to configure penalties for line angle changes in overhead power lines. Overhead power lines require more expensive and sophisticated structures if significant angle changes are encountered. An optimal centerline for an overhead power line avoids constraints and keeps as close to straight as possible. There are a few simple parameters that users can configure which will help compel Optioneer to follow this logic.
How to configure
The example below demonstrates a very simple alignment an overhead power line that demonstrates the principles of this design rule.
Overhead lines are constructed from straight lines between control points. If the bearing of adjacent point-point lines changes, Optioneer will record an angle change.
These line angle changes are penalised based on angle ranges defined by the user. The picture below shows angles categorised into small / good angle change (green) and high / problematic angle change (red).
Important notes
Users shouldn't set any penalty for a range of angles that contains 0 degrees value. This would mean that Optioneer would perceive every point as a changing angle which will lead to incorrect results.
Angles are calculated as absolute value so the direction of change of the angle (clockwise / counterclockwise) doesn't matter. The maximum value by which the angle can change is therefore 180 degrees.
Input / output summary
Input parameters
Name | Default value | Unit |
'perfect' angle range maximum penalty value | 0, 2, 0
| degrees, degrees, penalty points |
'preferable' angle range minimum maximum penalty value | 2, 10, 1 | degrees, degrees, penalty points |
'acceptable' angle range maximum penalty value | 10, 60, 3 | degrees, degrees, penalty points |
'problematic' angle range maximum penalty value | 60, 180, 10 | degrees, degrees, penalty points |
Output parameters
Name | Example value | Unit |
Number of towers with 'perfect' angle change | 44 | items |
Number of towers with 'preferable' angle change | 12 | items |
Number of towers with 'acceptable' angle change | 3 | items |
Number of towers with 'problematic' angle change | 1 | items |
Total 'angle change penalty | 765 | points |
This design rule can also provide visualisation of results along the centerline.
The plot can be accessed via:
Vertical Profile Chart > Composition > Penalty
Vertical Profile Chart > Composition > Angle
The penalty will be mixed with other sources of penalty points, giving a quick insight into main risks related to the option being studied. Angle will provide the exact angle value.