Vision Grid Navigator / application
Nodal load or generation in schematic view
Corresponding geographic view in 3D scene
Geographic view in 3D scene on photographic background |
Practical approach
With Vision Grid Navigator the Vision Network Analysis application is extended with an geographical viewer and editor. Instead of the detailed and demanding maps used in GIS applications a simple but widely used Falk digital map is taken as a background. On this map locations and surroundings are easily identified. Questions like: “On which side of the road is a cable buried?” or “Is a specific load in an industrial area?” are quickly answered.
Implementation
The map can be zoomed fluently from country to street level thanks to a high speed tile implementation. The whole map is implemented as a DirectX™ 3D model and can be tilted and rotated. The use of DirectX™ enables fast semi-transparent polygons and bars, blinking of lines and blinking of nodes.
Navigation
The main screen of Vision Grid Navigator consists of a map area and a tabbed page with a tree view component on the left. In this tree view networks can be added. Most Dutch utilities subdivide their service area into separate MV networks. Each network in the tree view correspond with a blue square on the map and represents the location of the network. By double clicking on a blue square or item in the tree view the corresponding network is opened. The network is drawn schematically in Vision Network Analysis, and geographically in Vision Grid Navigator.
Geographical coordinates
In Vision Grid Navigator nodes, lines and joints are shown on the map when their geographical XY-coordinates are present. These coordinates can be imported from the GIS of the utility. A line, e.g. a cable, can have many coordinates according to its trajectory. A node, e.g. a distribution transformer station, always has one coordinate. When the trajectory of a line is not known it will be drawn as a straight line between its nodes.
In edit mode the user can graphically move, add or remove coordinates from lines and nodes.
Appearance
In the tab page on the left of the screen, several settings can be made that change the appearance of the drawn scene on the map. With sliders, line width, node size, sleeve size and text size are adjustable. An adjustable transparent colour layer is available for better contrast between network and map background.
The colour of the lines and nodes in the geographic view correspond to the colours in the schematic view. These colours change when, for example, another view is selected or a calculation is done.
Interaction
The user can select lines or nodes by
clicking them or drawing a selection rectangle in the geographic view. The
selection in the schematic view is automatically updated. When the mouse pointer moves over nodes or lines they start blinking. In this way the complete trajectory of a specific cable can easily be seen. When the mouse pointer moves over lines lying upon each other, an extended hint is shown with the information of each individual line.
The information given in the hints can be configured by the user.
Filters
The results of the load flow calculation can be filtered by an adjustable selection criterion. There are two type of filters one for line loads and one for nodal voltages. If the user selects a filter, the whole network is drawn in a gray colour. Then for instance, only those lines can be highlighted that have a load of more than 70 percent. When adjusting the filter sliders, the objects that meet the criteria are instantaneously highlighted.
3D scene
The 3D map model implementation enables views from a certain horizontal and vertical angle towards the scene. The 3D model gives an extra dimension for presentation purposes. The user can select 3D bar graphs for viewing calculation results such as nodal short-circuit power or nodal voltages.
Also, some attributes of nodes such as amount of load, generation or number of customers can be shown in 3D bars. In this way the geographic distribution of this kind of information can easily be interpreted and used within the utility.
Overlays
Different map overlays can be imported and shown on the map. The import file format is the widely used Google Earth format KML.
For instance new plans for developing new residential or industrial areas can be imported and taken into account when designing networks.
Aerial photographs
When more detail is wanted aerial photographs can be shown as background. The photographs have a resolution of 0.25m per pixel. The accuracy of this photographic background on the Dutch RD projection grid is better than Google Maps/Earth’s implementation.
The photographic background has the same performance as the map.
