DS Plot Window

The DS Plot Window is a fully functional plotting tool that allows for quick display of results, printing of the plots, and several other features. We supply here a list of those features as well as some specifics that will help you understand what you are seeing in the plot window.

 The plot window includes printing of any plot.

 The DS Plot Window includes an Auto Plot Tab that automatically plots pertinent values depending upon the double-click action performed (clicking a motor breaker for example plots motor parameters). Refer to the next section for more detail.

 The DS Plot Window is updated at the end of a simulation, or after the pause of a step-run simulation.

 Plots are all created using the maximum number of points (defaults at 3000) supplied in the DS Options; but in reality, not exactly that number. Based on the simulation time step, the DS Engine determines the closest integer divisor into the number of simulated points to determine the number of points to be saved for plotting. They will not exceed the plot size defined in DS Options.

 There will be slight differences between times where events happen in the message log (which is the actual time of the event) vs. times when changes appear on the plots themselves. This is due to the natural down-sampling action needed to keep the plot within the size defined in the DS Options dialog.

 In addition to plot results down-sampling, the DS Engine automatically saves conditions on both sides of a switching event. Thus, at times, one might see places where there are two points with the same time, but two different values. This is due to saving results both before and after the network is resolved for a switching event.

 For more definition, increase the number of points plotted in the DS Options dialog.

 For all network components, plotted flow is calculated into the bus.

 Plot ID Names are automatically generated for each value you desire to plot. Those names appear in the legend and on the Y-Axis of the plot.

Auto Plot

For each double-click action that runs a simulation, an auto plot is generated (first tab in the DS Plot Window). The results plotted are pre-selected values corresponding to the double-click action. The auto plot is generated according to the guidelines presented in Table 3.

Table 3. Auto Plot Pre-Defined Values.

Double-Click On Plots Units

Generator Exciter Symbol Terminal Voltage pu

Field Voltage pu

AVR Voltage pu

Generator Governor Symbol Mechanical Power pu

Speed pu

Motor Breaker Terminal Voltage pu

Terminal Current pu

Speed pu

Torque pu

Generator Breaker Terminal Voltage pu

Field Voltage pu

Angle Degrees

kW kW

kVar kVar

Breaker on Network Device Bus Voltage nearest breaker pu

Amps through device Amps

kW through device kW

kVar through device kVar

Plot Printing

Printing of plots in the DS Plot Window falls in line with capabilities in the Harmonics and Power Protector Focus. The main controls used to Print and Print Preview are the Print and Print Preview buttons.

Print

Print Preview

After selecting Print or Print Preview, the Print Plot Dialog shown in Figure 39 will be displayed to prompt you with several choices for how you want your plots to appear. First, select the plots you desire to see under Print What. Under Scaling, you will find several fit-to-page options that change depending upon the number of plots you have selected to see.

Figure 39. Print Dialog showing default page option settings.

For example, if you select four plots as shown in Figure 40, three scaling options allow:

 Fit to Page - Fits One Plot per Page

 Fit to ½ Page - Fits Two Plots per Page

 Fit to ¼ Page - Fits Four Plots per Page

Once selected the plots will either Print or Print Preview as you have selected.

Figure 40. Print Dialog showing settings for four plots per page.

Figure 41. Example plot window ready to print.

As an example, a plot as shown in Figure 41 is ready to plot. The Print Preview of this plot is shown in Figure 42. Once the Print Preview is displayed, there are options that allow you to look at more pages (on a multiple plot Print Preview), Zoom In, Zoom Out, Close the Print Preview window, and finally to Print what you have previewed. These fall in line with standard Print Preview features in many Windows applications.

In Figure 43 we show the Print Preview that matches selections shown in Figure 40. Figure 43 is also shown in Landscape. If you desire to see your plots in Portrait, you will need to first open the Page Setup Dialog, shown in Figure 44. This can be found under File / Page Setup in the EasyPower menu.

Figure 42. Plot during a print preview with default settings.

Figure 43. Print Preview with four plots per page.

Figure 44. Page Setup Dialog.

Plot Zooming

When reviewing your plots, at some point you will most likely desire to zoom in to a section for closer scrutiny. EasyPower DS allows both X and Y axis zooming using the plot display control.

The plot display control.

Zoom Area Allows you to select any portion of your plot using a rubber rectangle.

First click on this button, and then left-mouse click and drag on the plot to zoom into the location you desire. An example of this action is shown in Figure 45 and Figure 46.

Zoom Out Full To restore the plot window to its original fully zoomed out view, click on this button, or double click on the mouse scroll wheel, if you have one.

Zoom In 1.5x Pressing this button will zoom in by 1.5 times.

Zoom In 1.5x Pressing this button will zoom out by 1.5 times.

Data View Shows and hides the spreadsheet data view where the curve data plotted is supplied in tabular form.

Data Cursor When pressed causes the cursor to also show digitized values as you move your mouse over the plot. The values are displayed in the legend.

Scroll Bars Shows and hides the plot scroll bars.

Figure 45. Plot with Zoom Area shown.

Figure 46. Results of Figure 44 Zoom Area.

Plot Horizontal Zooming

When you desire to zoom into an event for more detail, but desire the vertical axis scales to remain fixed, left-mouse click and drag directly on the plot without clicking on any of the buttons documented in the last section. This will perform a horizontal (Time Axis) zoom. Figure 47 shows the black zoom range while it is being selected, and Figure 48 shows the result of this action in the plot window.

Figure 47. Plot with horizontal zoom being applied.

Figure 48. Results of Figure 46 horizontal zoom.

Spreadsheet Data

The DS Plot Window inherently includes all plot data values for ready access if you need it. To quickly access the data, pull the splitter bar (shown in Figure 49), to the right. This reveals the plot data, thus allowing spreadsheet-like select and copy functions. An example of selecting a section of data is shown in Figure 50. To copy the data, either press Ctrl-C on the keyboard, or use the Copy button.

Copy

Splitter Bar

Figure 49. DS Plot Window showing spreadsheet data.

Figure 50. DS Plot Window showing selected spreadsheet data.

2.12 Scripts

Scripts in the DS Engine are used to define simulation actions. EasyPower DS has supplied a good amount of automatic simulation actions through quick double-click actions performed directly on the oneline (See Chapter 3). However, in a lot of situations, more simulation action detail is necessary to perform what is needed. For this case, the DS Engine allows you to create as many scripts as you want, each as long as you need.

Scripts have these limits:

 They perform no auto-plot action, and so plot definitions must be made to see any results.

 They are limited to the commands documented in the next section.

 Script commands are time dependent and chronological.

 To be run, they must be selected from the Script Load drop down list in the toolbar.

 They can only be run one at a time.

 They can only be created in the Script Edit Dialog.

2.12.1 Commands

Table 4 lists all presently available script commands.

Table 4. Script Commands.

Script Command Type Value1 Value2 Time

Fault Bus (R+jX) Network Change R-Ohms X-Ohms

Fault Bus For (R+jX) Network Change R-Ohms X-Ohms Seconds

Remove Fault Network Change

Run to Time Simulation Run Seconds

Run for Time Simulation Run Seconds

Close LV Breaker Network Change Close HV Breaker Network Change

Close Switch Network Change

Close Fused Switch Network Change

Open Switch Network Change

Open Fused Switch Network Change

Open LV Breaker Network Change

Open HV Breaker Network Change

Transfer ATS Network Change

Script Command Type Value1 Value2 Time Enable Contactors Override DS Options

Disable Contactors Override DS Options Enable Prot Devices Override DS Options Disable Prot Devices Override DS Options

Set Time Step Override DS Options Seconds

AVR to Manual Alter AVR Mode

AVR to Auto Alter AVR Mode

Step AVR Alter AVR Mode % Step

Set Governor Speed Setpoint Alter Governor Mode pu Value

Set Exciter Parameter Alter Model Data Row # Value Set Governor Parameter Alter Model Data Row # Value Set Generator Parameter Alter Model Data Row # Value Set Stabilizer Parameter Alter Model Data Row # Value Set Motor Parameter Alter Model Data Row # Value Notes:

1. If the fault impedance is specified as zero, the impedance value will be automatically limited to 0.0 + j1.0 E-10 per unit Ohms. No smaller value is allowed.

2. Only one fault may be applied at a time. If another fault application is attempted, it will be ignored, and the operation of fault removal will only correspond to the first fault application.

3. Repeated ATS Transfers will toggle the ATS back and forth from Normal to Emergency connections.

4. Changing the time step will have impacts on plot length and can trigger an error in cases where the plot length is too short. We suggest changing overall simulation time step in the DS Options Dialog.

5. The pu Value specified when setting the Governor Speed Setpoint is dependent upon each governor model. Some specify speed as a pu change, where rated speed is 0.0, and others specify speed in pu where 1.0 is rated speed.

6. Row # in the table above is the parameter row number starting with 1, as seen in the data spreadsheet of the Stability Tab for a generator or motor. For example, an IEEE AC1A excitation system has gain KA specified in row 7 of its parameter list. Use 7 as the Row # to change this exciters value of KA at run-time.

7. For all model parameter setting commands, values are hard set. This means that no special data integrity checks are performed to validate the parameter value, and it means that whatever value was there is replaced immediately at the time in the simulation that the change is being made. There are a handful of details and exceptions to consider:

 Models with saturation have the internal saturation variables updated if any saturation parameter is modified. Without this extra step, changing the saturation parameters would actually do nothing.

 IEEET1 and IEEET2 exciter models include modifying KE at initialization to include effects of saturation. If KE is ever set at runtime, this initialization is not repeated, and KE is hard set overriding whatever value of KE was determined.

 For the Woodward Diesel governor model, the last parameter, +1 specifies droop control and -1 specifies isochronous control.

 For the Round Rotor and Salient Pole generator models, changing X’’d also changes X’’q to the same value.