SLD editor
What it does
In Phasor, the single-line diagram (SLD) is not a picture of the model. The diagram is the model. When you place a transformer symbol, you create a transformer element. The rating, the impedance, the tap range and the vector group are properties of that symbol. The solvers read the data from the symbol directly.
There is no separate data table. Because of this, the diagram and the network data cannot disagree.
The symbols follow the IEC 60617 standard. Phasor gives each voltage level its own color. For example, you can see the difference between a 33 kV feeder and an 11 kV feeder immediately.
How to build a network
- Place a source. A source is a grid supply point or a generator.
- Add a busbar. Connect the source to the busbar. A busbar extends automatically to reach its connections. You do not draw the busbar again when you add a circuit.
- Build outward. Add transformers, lines, cables, switches and loads. The snap function keeps the connections at right angles.
- Enter the data when you place each element. The inspector shows the fields that the element needs. If a field can have only one possible value, Phasor enters that value for you. For example, the voltage rating of a cable comes from the voltage level of its connection.
- Arrange the diagram when you are ready. Auto-arrange is one command that you start yourself. The result is a normal edit. You can undo it. Phasor does not move symbols while you work.
- Run a study. Read the results on the diagram: a voltage heatmap on the buses, the loading on the branches, and a flag on each element that has a violation.
Three rules of the editor
Rule 1 — Your layout is your data. When you set the position of an element, Phasor keeps that position. Phasor does not move the element when you open the project, when you add an element near it, or when you run a study again. A diagram that you arranged for a report stays arranged.
Rule 2 — The view does not move while you drag. When you drag an element, the element moves with your cursor. The canvas does not pan or zoom during the drag.
Rule 3 — Each change goes through one command gate. Each edit is recorded as a command. This includes a drag, a field change, an auto-arrange and a deletion. Because of this, undo always works, and it always removes exactly one change. MCP automation uses the same command gate. A script can make the same changes that a person can make, and no more.
Inputs and outputs
Data that you enter
| Element | Necessary data |
|---|---|
| Grid supply point | Nominal voltage, fault level, X/R ratio. |
| Generator | Rating, dispatch, sequence impedances, reactive power (Q) limits. |
| Transformer | Rating, voltage ratio, impedance, vector group, tap range and tap step. |
| Line / cable | Type, length, sequence impedances per km, continuous rating. |
| Busbar | Voltage level, rating, and its sections. |
| Switch / breaker | Normal state (open or closed), rated breaking capacity, protective device. |
| Load | P and Q for each scenario, and the load model (constant power, constant current or constant impedance). |
Results that the canvas shows
| Output | Notes |
|---|---|
| The model | The same object that each solver reads. |
| Annotated diagram | Label size is set in screen pixels. Labels stay easy to read at each zoom level. |
| Result overlays | Voltage, loading and violation state for each element. |
| Export | Vector or raster image for reports, with the layout that you arranged. |
Notes
Phasor places the labels for you. When two labels touch, Phasor moves the label with the lower priority. A substation with many elements stays easy to read. Label size is set in screen pixels. When you zoom in, you see more of the diagram. The letters do not become larger.
The normal state of a switch is model data. When you open a switch, the network can divide into islands. The solvers report this condition. Use Graph Space to see the islands directly.
Names, not identifiers
Each element keeps the name that you give it. That name appears in the results, in the violation lists and in the solver messages. You do not see internal identifiers.