PowerWorld Simulator version 11. Manual

Series Capacitor Fields on Onelines

Series capacitor f ields are used to show field values specific to series capacitors.

Run Mode

If the Series Capacitor field for capacitor status is displayed, the capacitor status can be toggled in run mode when

you left-click on the field.

Right clicking on the series c apacitor field gives the option to display the Series Capacitor Field Dialog or the

Line/Transformer Information dialog.

Edit Mode

To enter a new series capacitor field, select Insert > Fields > Series Capacitor Field from the main menu or the

Series Capacitor Field button on the Insert Toolbar, and then click on or near the series capacitor object for which

you want to add the new field. This calls up the Series Capacitor Field Dialog. Enter the from and to bus numbers

associated with the device (the default values for these fields correspond to the series capacitor on which you

clicked), and the circuit number of the device. Enter the total number of digits that the field should display, as well

as the number of digits to the right of the decimal point. Finally, specify what the field should display: the capacitor

status or the series capacitance.

To modify the parameters of an existing series capacitor field, position the cursor anywhere on the object and right-

click to bring up the Series Capacitor Field Dialog. Use the Format > Display/Size main menu option to change

various display attributes for the series capacitor field, including its font and background color. Finally, you can use

the Format > Font option to change the font for selected fields on the display.

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Building a Oneline Diagram

Switched Shunts

Switched Shunt Display Objects

Switched shunts are either capacitors that supply reactive power to the system or reactors that absorb reactive power.

Simulator represents switched shunts as a number of blocks of admittance that can be switched in a number of

discrete steps or over a continuous range. Switched shunt display objects come equipped with a circuit breaker that

indicates the shunt's status. If the switched shunt is closed, the circuit breaker appears as a filled red square. If the

switched shunt is open, the circuit breaker appears as a green square outline. To change the status of the switched

shunt, click the corresponding circuit breaker.

Switched shunt fields are often placed next to switched shunts to indicate the amount of reactive power supplied by

the device. For switched shunts with such a field, you can manually increase the reactive power supplied by the

device (provided its control mode is discrete) by clicking on the up-arrow associated with the device's reactive power

field. Likewise, you can decrease the reactive power supplied by the device by clicking on the down-arrow. To make

the up/down arrows visible, set the Delta per Mouse Click on the switched shunt field to a nonzero value.

Right-clicking on the switched shunt displays the Switched Shunt Dialog. Use the Switched Shunt Dialog to inspect or

modify the model of the switched shunt.

You can add a new switched shunt to the case in Edit Mode. Select Insert > Switched Shunt from the main menu, or

click the Switched Shunt button on the Insert Toolbar. Then click the bus where you would like to attach the device.

The Switched Shunt Dialog will appear. The bus number is automatically determined from the bus to which you

attached the capacitor. Enter the size, the thickness of the pen [in pixels] used to draw the device, and its orientation.

The Nominal Mvar field gives the amount of reactive power the device would supply if its terminal voltage were 1.0 per

unit. The Control Mode field determines whether the switched shunt has a fixed value or will vary discretely or

continuously within its operating limits to maintain its terminal voltage within the voltage range specified in the Voltage

Regulation field.

The amount of shunt admittance is specified in the Switched Shunt Blocks table. The columns in this field correspond

to different blocks of admittance. The first row indicates the number of steps in each block, and the second row gives

the amount of nominal Mvars per step. The switched shunts are always switched in the order specified in this field.

Select OK to add the device. If you do not want to add the switched shunt to the case, select Cancel.

To modify the parameters for an existing switched shunt, position the cursor on the device and right-click. This again

brings up the Switched Shunt Dialog. You can then change any parameter of the switched shunt. Choose Format >

Display Appearance from the main menu to change the color and/or line thickness.

To delete an existing switched shunt, use the Edit > Cut or Edit > Delete menu items.

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Switched Shunt Fields on Onelines

Switched Shunt field objects are used primarily to indicate various quantities associated with switched shunt devices.

Furthermore, some switched shunt field types, which are distinguished by an integrated spin button, may be used to

change switched shunt device properties.

Run Mode

For switched shunt fields with an associated spin button, clicking on the up/down arrows will change the value of the

associated field.

Right clicking on a generator field gives you the option to open the Switched Shunt Field Dialog or the Switched

Shunt Information Dialog.

Edit Mode

Simulator offers two options for adding switched shunt fields to a oneline in Edit Mode. If you need to enter only a

single field, the easier approach may be to choose Insert > Field > Switched Shunt Field from the main menu or

the Switched Shunt Field button from the Insert Toolbar and then select the switched shunt to which you want to

add the field. This invokes the Switched Shunt Field Dialog. Enter the bus number associated with the device (the

default is the bus associated to the closest switched shunt to the field), the ID field, the total number of digits to

show, and the number of digits to the right of the decimal point. Next, select the type of field to show.

The second approach for adding new switched shunt fields entails right-clicking the bus and selecting Add New

Fields Around Switched Shunt from the resulting local menu. Please see Inserting and Placing Multiple Display

Fields for more details.

To modify the parameters of an existing swtched shunt field, position the cursor anywhere on the object and right-

click. This brings up the Switched Shunt Field Dialog. Choose Font > Line/Fill, or Font > Display/Size from the

Format menu to change various display attributes of the field, including its font and background color.

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Building a Oneline Diagram

Interfaces

Interface Display Objects

Interface display objects are used on the onelines to visualize the flow of power through an interface record. Interface

records are used to show the net real power (MW) flow on a group consisting of one or more of the following devices:

1) transmission lines and/or transformers, 2) total tie-lines between two adjacent areas, and 3) total tie-lines between

two adjacent zones. Only area-area and zone-zone interface records can be displayed using interface display

objects.

Interfaces, like transmission lines, are represented as multi-segment lines, except that they may be drawn between

area/zone objects in addition to buses. Drawing interface display objects involves the same steps as drawing

transmission lines and transformers. The line thickness and color of interface objects may be customized by selecting

Format > Display/Size from the main menu.

Interface Fields and Interface Pie Charts are often placed close to or on the interface to indicate the power flow

through the device.

Run Mode

When animation is active, the flow of the arrows on the interface object may represent either the MW flow through

the interface or the currently calculated power transfer distribution factor (PTDF) pertaining to that interface. You

can customize the appearance of the animated flows using the Animated Flows Tab of the Oneline Display Options

Dialog available using the local menu.

Right-click on the interface to view the Interface Dialog for the interface.

Edit Mode

The quickest method of inserting new interface objects is to use the Options > Auto Insert Interfaces. Please see

Automatically Inserting Interfaces for details.

To manually add a new interface object to the case, first select Insert > Interface from the main menu, or click the

Interface button on the Insert Toolbar. Then place the cursor on the starting location for the interface (usually an

area/zone object or a bus object) and left-click. Add more segments to the interface by moving the cursor and the

left-clicking at the end of the segment. To finish adding an interface, place the cursor on the terminal object for the

interface and double-click. This then calls up the Interface Dialog. Either select an existing interface, or define a

new interface (see Interface Dialog for details).

Interfaces can be anchored to either area/zone objects or bus objects.

To change the shape of the interface, first left-click on the object to select it. This causes handles to appear at each

vertex. You can then move any vertex by dragging it with the left mouse button down. To remove a vertex, hold

down the CTRL key and then click the vertex you would like to delete. To add a vertex, hold down the CTRL key

and then click on the interface where you would like to add the vertex.

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Automatically Inserting Interface Display Objects

The Automatic Insertion of Interfaces Dialog is used to automatically insert interface objects on the oneline diagram

between existing area/zone display objects. Interface pie chart objects can also be inserted as part of this process.

The automatic insertion of interface display objects greatly accelerates the construction of interface diagrams, which

are particularly useful for animating the results of PTDF calculations. Only area-area and zone-zone interface records

can be displayed using interface display objects.

The following procedure describes the quickest way to create an interface diagram for showing PTDF information and

area-area or zone-zone flows. It steps through the process from the creation of area-area or zone-zone interface

records to the addition of the area or zone display objects and, finally, to the automatic insertion of interface display

objects.

· Select Case Information > Interfaces from the main menu to bring up the Interfaces Display.

· Right-click on the Interface Records Display to show its local menu. Select Auto Insert Interfaces from the local

menu. This generates the Auto-Insert Interfaces Dialog.

· Use the Auto-Insert Interfaces Dialog to create the area-area or zone-zone interface records automatically.

At this point, the interface records have been created automatically. We now want to generate an interface diagram,

with the interface display objects added to it automatically.

· On a oneline diagram (either an already open diagram or a brand new one created by choosing File > New Oneline

from the main menu), place area/ zone objects at the desired locations.

· Select Insert > Auto Insert > Interfaces to display this dialog.

· Check the Insert Pie Charts on Interfaces box to automatically insert interface pie chart objects when the

interfaces are inserted. If this option is selected, change the Default Size of Interface Pie Charts to specify their

size.

· Select OK to insert the new oneline objects. New interface objects are automatically inserted between any

area/zone objects that have a corresponding interface record that is not already represented.

Note that you can do this automatic insertion as often as you like. The Number of Interfaces Not Shown field

indicates how many interfaces still need to be added to the diagram to represent all defined area-area or zone-zone

interfaces. It is a read-only field.

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Building a Oneline Diagram

Interface Pie Charts on Onelines

Interface pie charts are used to graphically show the percentage loading on an interface record. The amount of

shaded region of the pie chart indicates how close the interface is to its limit (provided the interface has a nonzero

limit). The appearance of the interface pie charts, including their color and the ability to automatically change size

based upon loading level, can be customized on the Oneline Display Options Dialog.

Right-clicking on the interface pie chart displays the Interface Pie Chart Dialog. This dialog can be used to customize

the size of the pie chart, or change the interface's limit.

Edit Mode

To enter a new interface pie chart, select Insert > Interface Pie Chart from the main menu or click the Interface

Flow Pie Chart button on the Insert Toolbar. Then, click the left mouse on the interface object with which you want

to associate the pie chart. This calls up the Interface Pie Chart Dialog, which is used to customize the appearance

of the pie chart.

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Oneline Links

Links to Other Onelines

Run Mode

Oneline links are one of the mechanisms used in Simulator to allow you to view multiple oneline diagrams on the

same screen. By default, the oneline links are shown as blue rectangles surrounding a text identifier of the linked

oneline diagram. Double-clicking the left mouse button anywhere within the oneline link object will display the

linked oneline diagram, even if it has not already been opened.

The ability to associate multiple oneline diagrams with a single case may prove particularly helpful when dealing

with large cases. If a single oneline diagram is used to display a case having many buses, the diagram may

become cluttered, and it will be difficult to analyze the case in sufficient detail. The ability to associate additional

onelines with the case and to call up those additional onelines using one-links can significantly enhance your view

of the system.

Note that you can also use the File > Open Oneline command from the main menu to open any oneline diagram

(*.pwd) file directly. See Opening a Oneline Diagram for further details.

Edit Mode

To add a new oneline link to a oneline diagram, first select Insert > Oneline Link from the main menu, or select the

Link button on the Insert Toolbar. Then, click the left mouse button at the location where you would like to display

the new link. The Oneline Link Options Dialog box will open, asking you to enter the name of the file that stores the

linked oneline and a caption for the clickable oneline link object. Note that you can enter simply the name of the

oneline file in this location. Simulator will look in the same directory as the case file by default. However, you can

also specify additional directory locations to search for oneline diagrams by opening the Solution/Environment

Options, switching to the Oneline tab, and using the Edit Oneline Browsing Path option to add additional search

locations for oneline diagrams

To modify the parameters of an existing oneline link, position the cursor anywhere on the object and right-click.

This invokes the Oneline Link Options Dialog, allowing you to change the identity of the linked file and the caption.

Select Format > Display/Size from the main menu to modify various display attributes of the oneline link, including

font size and background color.

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Building a Oneline Diagram

Document Links on Onelines

Just as you can link to other oneline displays from a oneline diagram using oneline link objects, you can also link to

documents and data on the world-wide web using Document Link Objects. When you click on Document Link Objects

in Run Mode, your system's default browser will be launched to retrieve the linked URL address. This feature is not

only for web URL's, though. Any file can be linked and its associated application will automatically open. This means

that power point files, word documents or spreadsheets can also be linked.

To add a Document link to a oneline diagram, select Insert > Document Link from the main menu. Then, click the

left mouse on the oneline diagram at the position where you would link to insert the Document link. The Document

Link Options Dialog box will appear, asking you to specify the world-wide web address to which to link as well as a

clickable caption to display on the oneline diagram. Enter the requested information and press OK to add the

Document link object to the oneline.

To modify the caption or address for a Document link object, right-click anywhere on its text. Specify its new

parameters in the Document Link Options Dialog and press OK. You may also modify various aspects of its

appearance, including the font size, by choosing Format > Display/Size from the main menu.

Note that Document links are active only in Run Mode. Clicking on a Document link object from the Edit Mode will

have no effect other than to select the object for placement, formatting, etc.

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Background Objects and Text

Background Lines on Onelines

The background of an oneline diagram can display added lines, polylines, and filled polygons among other items.

Edit Mode

To add a new background line, first select Insert > Background Graphic > Background Line from the main menu

or click the Background Line button on the Insert Toolbar. To draw a series of straight line segments on the

background, follow these steps:

· Position the mouse cursor where you want the series to begin and click and release the left mouse button.

· Move the mouse to the desired termination point of the first line segment. A straight segment will follow your

mouse movements. Click and release the left mouse button to complete the line segment and prepare for

drawing the next line segment, or double-click if this line segment is the last segment you wish to draw.

To draw a freehand shape rather than a series of straight line segments, click and hold the left mouse button where

you would like the freehand shape to begin and drag the mouse to trace the shape you desire (while holding the left

mouse button down). Release the left mouse button to complete the section of the freehand shape you have been

drawing. At this point, you can add either another freehand section or a straight line segment. When you have

finished drawing in the background, double click the mouse button.

Note that background display objects composed of straight line segments display significantly faster than lines

drawn freehand. Lines draw freehand (holding down mouse button) leave a vertex point at every point on the

screen, where a line composed of straight-line segments (left-clicking only where you want a vertex point) takes

considerably less effort for the PC to draw.

Use the Format > Display/Size command to change the color, line thickness and fill color associated with the line.

If the Use Background Fill option on the Line/Fill Tab of the Edit Multiple Objects Dialog is checked, the line is

assumed to be a polygon, with a line automatically drawn between the first point on the line and the last point. The

polygon is filled using the color specified in the Fill Color Field.

To change the shape of the line, first left-click on the line to select it. This causes handles to appear at each vertex.

You can then move any vertex by holding the left mouse button down and dragging the vertex to a new location. To

remove a vertex, hold down the CTRL key and then click the vertex you would like to delete. To add a vertex, hold

down the CTRL key and then click on the line where you would like to add a vertex. Note that freehand lines are

nothing more than a continuous series of vertices.

156

Building a Oneline Diagram

Background Pictures on Onelines

The background of an oneline diagram can display a variety of objects, including lines, filled polygons, and even

pictures. The latter will be discussed in this section.

Edit Mode

Simulator can insert bitmaps, jpegs, enhanced and standard metafiles, and icons from files into the oneline

diagram. These pictures may either serve as a background or appear above other objects on the oneline.

To add a picture object to the oneline diagram, select Insert > Background Graphic > Picture from the main

menu. Then, click the oneline diagram at the point where you would like the top left corner of the graphic to be

placed. The Open Picture Dialog will open, asking you to select the graphic file that you want to insert. When you

select a file from the dialog, the dialog displays a preview image so that you can be sure that you are selecting the

right file. When you have identified the file to insert, click OK. The image will then appear on the oneline. It may be

resized by dragging its resizing handles.

By default, pictures are inserted at the middle stack level. Thus, they hide most other oneline display objects. To

change the stack level of the picture, click it to select it, and then select Format > Display/Size from the main

menu. From the Line/Fill Tab , select the stack level of your choice. The Base stack level places the picture below

all other oneline display objects, while the Top stack level will cause the picture to obscure all other display objects.

To resize or reshape an existing picture object, click on it to select it and then drag its resizing handles. To change

the stack level of an existing picture object, click on it to select it and then select Format > Display/Size from the

main menu for access to the Line/Fill Tab , from which you can modify the picture's stack level.

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Converting Background Lines

Background lines can be converted to other objects by splitting, merging, or converting to power system objects. To

convert a background line, click with the right mouse button on a selected background line and the local menu will be

displayed with the conversion options. Most options are available if only a single background line has been selected

and no other objects are selected. The following options are available for converting a background line:

Split Background Line

A background line can be split at a vertex or anywhere along the line. Click the point on the line where the split

should be made and then click with the right mouse button and select the Split Background Line… option from the

local menu. Two background lines will result. This option is available only if exactly one background line has been

selected and no other objects have been selected.

Merge Background Lines

This option is only available if exactly two background lines have been selected. The two selected background lines

will be merged at the two closest ends and a single background line will result.

Convert to ac Transmission Line

After selecting this option, the Line/Transformer Information dialog will be displayed. The dialog options can be set

the same as they would be set when inserting an ac transmission line from the Insert menu. This option is available

only if exactly one background line has been selected and no other objects have been selected.

Convert to Bus

After selecting this option, the Bus Information Dialog will be displayed. The dialog options can be set the same as

they would be set when inserting a bus from the Insert menu. This option is available only if exactly one

background line has been selected and no other objects have been selected.

Convert to Substation

After selecting this option, the Substation Information Dialog will be display. The dialog options can be set the same

as they would be set when inserting a substation from the Insert menu. This option is available only if exactly one

background line has been selected and no other objects have been selected.

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Bus Renumbering Dialog

The Renumber Buses Display allows you to change the bus numbers for either the entire power system case, and/or

for any open oneline diagrams. To show this display, select Tools > Renumber Buses.

The bus renumbering feature is provided because it is sometimes necessary to renumber buses in the power system

model, either to make room for new buses or to move buses to a different zone or area that has a different numbering

scheme. It may also be necessary to renumber bus display objects on the oneline if you want to use the oneline with

a case other than the one for which it was originally designed. The bus-renumbering feature provides a convenient

way of accomplishing this.

The table at the bottom of the Bus Renumbering Dialog is used to manage the lists of current bus numbers and any

desired changes to the numbering scheme. You can specify the bus numbers to change and their new values by

directly typing them into the table. Alternatively, you can generate the bus list automatically by selecting one of the

Automatic Setup of Bus List Options and clicking the Setup Bus Swap List button. The Automatic Setup options

allow you to add to the list all buses in the case, all buses in the case subject to the area/zone/owner filter constraints,

all buses currently displayed on the oneline, or a set of numbers from a text file.

The table behaves just like a Case Information Display and thus has a local menu that can be invoked by clicking the

right mouse button. Select Insert from the local menu to insert a new bus number to change, or select Delete to

delete a bus number that is currently in the list. Select Show Dialog to display the Bus Information Dialog

corresponding to the bus number on which you right-clicked. You may clear the entire list by pressing the Clear Bus

List button.

Once you have indicated which buses you would like to renumber in the table, select an option from Bus Change

Options to specify where you would like to implement the changes (in both the case and the oneline, in the case only,

or in the oneline only). Make the changes by pressing the Change Bus Numbers button. Close the dialog by

pressing Close.

The option groups at the top of the dialog deserve further discussion. See Bus Renumbering Options for further

details or click NEXT.

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Edit Mode Tools and Options

Bus Renumbering: Automatic Setup of Bus List Options

This section of the Bus Renumbering Dialog is used to generate automatically a list of the buses to be renumbered.

Select an option from the list and click on the Setup Bus Swap List button to generate the list, or Clear Bus Swap

List to clear the list.

Load All Buses in Cases

Creates entries in the table for every bus in the system. By default the new bus number is the same as the old bus

number. Of course you do not have to renumber every bus. If you would like a bus to keep its same number, either

add that bus to the table, or simply have an entry with the old and new bus numbers identical.

Load Buses with Valid Area/Zone Filters

Same as the Load All Buses In Case option except only those buses with valid area/zone/owner filters are added.

This allows you to easily modify the bus numbers in just an area or zone.

Load Only Buses on Oneline

Creates entries in the table only for those buses on the current oneline. This option is most useful when you are

just changing the buses on the onelines.

Load Buses From Text File

Creates entries in the table using an external text file. The format of this file is as follows:

Specifies converting from old bus number 1 to new bus number 11

Specifies converting from old bus number 2 to new bus number 22

etc.

Freshen Current Oneline

The Freshen Buses option is designed to help you quickly renumber an existing oneline to work with a new

numbering scheme. You will find this method helpful if you have been using the oneline with a case and now must

use it with a different case having a different set of bus numbers, but the same bus names. Freshen Buses will try to

match the buses on the oneline with the buses in the new case by matching bus names and kv, rather than by

number (which is how Simulator usually tries to link bus display objects with bus records in the case). The best way

to learn how to use Freshen Buses is to consider the following example:

To update an old oneline to work with a new bus numbering scheme:

· Open the oneline and the old case with which it was used.

· Choose Options/Renumber Buses from the edit-mode menu.

· Select "Load Only Buses on Oneline" and press the "Set up Bus Swap List" button.

· Change the "Swap?" field values all to Yes.

· Right click on the table and choose Save List to File. Give the file a name. For this example, we'll name the file

"oldscheme.txt." This file will contain the list of buses represented on the oneline, specifying each bus's

number, name, kv, and area.

· Close the old case.

· Open the new case and the oneline you wish to renumber. If any other onelines open with the case, close

them. You w ant only the oneline you wish to renumber to be shown.

· Choose Options/Renumber Buses from the edit-mode menu.

· Select "Freshen Current Oneline" and specify the file "oldscheme.txt" (for this example). Click the "Set up

Swap List" button. Simulator will match the old numbering scheme used in the oneline with elements in the new

case by name and kv. If it finds more than one match, it will use the element's area name as a tie breaker. If it

still can't reconcile the multiple matches, it will add both renumbering options to the table.

· Go through the new list and make sure that you want to swap the buses that are listed. If you do, change the

"Swap?" field value for each to Yes (you can do this quickly for all buses by right-clicking on the Swap? column

and choosing "Toggle All Yes." Be sure to reconcile any duplicate bus renumbering suggestions. These are

cases for which Simulator could not determine how to renumber the buses a bus on the diagram matches more

than one bus in the case by name, kv, and area.

· Click the Change Bus Numbers button at the bottom of the form.

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Merging Buses

Two or more buses can be merged to a new bus in "Edit Mode" with the loads, generators, and shunts of the buses

merged moved to the new bus. The transmission lines among the buses merged will be deleted while the transmission

lines connecting the merged buses and buses which are not selected to merge will be moved to the new bus.

To join two or more buses together, select at least two power system elements (at least one of them being a bus), then

right click to invoke the one-line popup menu and select Merge selected buses. Specify the buses to merge further if

needed by clicking Add and/or Delete button. To add buses to merge, click Add and select all the needed buses in

the Choose a Bus dialog and click OK. To delete from already selected buses, select the buses to delete and click

the Delete button.

Once you have the elements to merge selected, enter the number, name, nominal voltage, zone number, area number

and substation number for the new bus. These properties can be set to be the same as one of buses to merge by

selecting it in the Specify buses to merge box and pressing the Set new bus properties same as selected bus .

Buses can also be merged in the Bus Records case information display. To do so, select a cell and right click to popup

the local menu. Select Merge selected buses which is the third item in the second group. The buses to merge and

the properties of the new bus can be edited in the Bus Merging Dialog.

When buses are merged from the one-line diagram, the selected buses will be joined in both the PWB case and the

one-line. When buses are merged from the bus grid, the selected buses will be joined only in the PWB case but not in

the one-line. This might result in bus objects not connected to bus records in the one-line.

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Edit Mode Tools and Options

Splitting Buses

Simulator assists you in transforming one bus into two connected buses. This process is called splitting a bus. In

performing the split, the user is able to decide which equipment to keep connected to the original bus and which

equipment to move to the new bus. Because this activity impacts the structure of the power flow equations, bus

splitting can be performed only in Edit Mode.

To split a bus from the oneline diagram, right click on the bus you wish to split, and click Split from the resulting local

menu. To split a bus from the Bus Case Information Display, right-click on its corresponding record and again click

Split from the resulting local menu. In either case, the Bus Split Dialog will appear.

Multi-section lines merit special consideration during bus split operations. These are the rules Simulator follows when

you try to split a bus that is part of a multi-section line. If the original bus is the endpoint bus of a multi-section line and

the ending line segment was transferred to the new bus, then the new bus becomes the new ending terminal of the

multi-section line. If the original bus was a dummy bus of the multi-section line, and if exactly one of the branches

connected to the original bus is rerouted to the new bus, then both the new bus and the original bus will be dummy

buses in the reconstituted multi-section line. If neither or both of the lines connected to the original dummy bus were

rerouted to the new bus, then the multi-section line definition is eliminated, since Simulator has no way to determine

how the multi-section line should be redefined.

A final consideration involving bus splits is how sequence data is treated. If you have defined sequence data for fault

analysis, Simulator will recalculate the sequence data for the original and new buses after the split. In this case, the

zero sequence impedance for the new branch that connects the original and the new bus will be set to j0.0001.

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Split Bus Dialog

The Split Bus dialog contains two sections labeled Existing Bus and New Bus . These sections enable you to

designate the bus you want to split and the name and number of the new bus created by the bus split operation. If you

opened the Split Bus Dialog from either the Bus Case Information Display or an oneline diagram, the Existing Bus

Name and Number fields will be read-only and will identify the bus you selected. How ever, if you opened the Split Bus

Dialog from Simulator’s main menu, you will first have to choose a bus to split. In this case, use the Find… speed

button located next to the Existing Bus label to select the bus to split, or simply type its number in the Existing Bus

Number field. Then, provide the name and number for the new bus to create using the New Bus Name and Name

fields. The number you specify in the New Bus Number field must be unique; it cannot be a number that identifies

another bus in the case. If you do specify an existing number, Simulator will issue an error message and require you

to specify a different number. If you choose not to specify a name for the new bus, Simulator will set the name of the

new bus to be the same as the bus’s number.

Once you have identified the bus to split and the name and number for the new bus resulting from the split, you may

then specify whether a bus tie should be inserted between the existing bus and the soon-to-be-created new bus. By

checking the Insert bus tie between existing and new buses checkbox, you command Simulator to place a very

low -impedance bus tie between the bus to split and its offspring. The new branch will have an impedance of 0.0000 +

j0.0001 ohms. If the bus tie should be inserted as an open branch, check the Normally open checkbox. This option

becomes available, of course, only if you elect to have Simulator automatically add the new bus tie.

After you have finished making your selections, click OK. Simulator will create the new bus, assign its electrical

attributes to match those of the existing bus, and add the bus to the power system model. If a oneline diagram is

currently active and the existing bus is represented on it, Simulator will add a symbol for the new bus to the diagram,

placing it immediately to the right of the existing bus’s symbol. If you elected to create a bus tie between the existing

and new buses, Simulator will also add a symbol for the bus tie to the diagram.

Finally, Simulator will automatically open the Equipment Mover Dialog to help you manage the transfer of equipment

from the existing bus to the new bus.

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Edit Mode Tools and Options

Equipment Mover

Simulator provides a convenient tool for transferring equipment between buses. Simulator allows you to move bus

shunts, loads, generators, switched shunts, and transmission lines between buses. For loads, generators, and both

varieties of shunts, Simulator offers you the ability to transfer all or part of the equipment from the origin bus to the

destination bus.

Equipment may be transferred between buses using the Equipment Mover Dialog. The Equipment Mover Dialog can

be opened in any of four ways:

· From the main menu, choose Options / Tools > Move Bus Equipment …

· Right click on the bus from which you want to move equipment and select Move Equipment… from the resulting

local menu.

· From a Bus Case Information Display, right-click on the record corresponding to the bus from which you want to

move equipment and select Move Equipment … from the resulting local menu.

· As the final step of the Bus Split operation.

Regardless of the approach you take, Simulator will then open the Equipment Mover Dialog. The Equipment Mover

Dialog consists of three sections. The top portion of the dialog is split in two sections that identify the bus from which

equipment will be transferred (on the left) and the bus equipment w ill be transferred to (on the right). If the dialog was

opened as the final operation of the Bus Split operation, these two buses will be hard-coded to identify the original bus

and the bus resulting from the split. If the dialog was opened from the main menu, you must select both the origin and

destination buses from lists that are reminiscent of case information displays. If the dialog was opened using one of

the other two methods, the origin bus will be set to the bus you selected, and you will then have to choose the

destination bus. To select a bus to be an origin or destination bus, simply select the corresponding record from the

appropriate list.

Once the origin and destination buses have been identified, you must then select the equipment to transfer from the

origin to the destination bus using the case information display that occupies the bottom of the dialog. To move a

particular piece of equipment, toggle the value of the Move Object? field to YES. To move just portions of loads,

generators, or shunts from the origin to the destination bus, adjust the value of the Move % field from 100.0 to the

percentage you desire.

Once you have selected the equipment you wish to transfer, click the Move equipment button. Simulator will adjust

the power system model to reflect your equipment transfer requests. Furthermore, Simulator will provide you an

opportunity to manually adjust all open oneline diagrams to reflect the equipment transfers. To facilitate this activity,

Simulator will open a Potential Misplacements Dialog for each oneline that displays the origin bus. The Potential

Misplacements Dialog lists the display objects associated with the equipment that had just been transferred from the

origin to the destination bus. By clicking on an entry in this list, you can pan the associated oneline diagram to focus

on that object. This allows you to identify display objects that perhaps should be relocated to reflect their new bus

associations. Once you have finished addressing these potentially misplaced display objects, click the OK button to

close the Potential Misplacements Dialog.

If you find that you would like to reopen the Potential Misplacements Dialog after you have closed it, click the List

most recent transfers button. This will reopen the Potential Misplacements Dialog associated with the most recent

equipment transfer operation.

To conclude the equipment transfer operation, click the Close button.

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Edit Mode Tools and Options

Tapping Transmission Lines

Simulator eases the process of inserting a bus at some location along an existing transmission line. This feature can

be extremely useful when you want to add a new generation site to a model, for example. Rather than having to

delete an existing line, place the bus, and draw two new transmission lines, Simulator simplifies the task to a one-step

process.

A line can be tapped from a oneline diagram, the transmission line case information display, or by choosing Tap

Transmission Line from the Tools menu. From the oneline diagram, right-click on a transmission line and select

Insert Line Tap from the popup menu. From the case information display, simply right-click on the corresponding

branch record and select Tap Transmission Line from the popup menu. Either of these methods will open the

Automatic Line Tap dialog for setting up and inserting the new bus.

Note that transmission lines may be split only from Edit Mode. You cannot access this functionality from Run Mode.

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Automatic Line Tap Dialog

The Automatic Line Tap Dialog will allow you to define the settings to use for inserting a new bus along a transmission

line. The transmission line to tap will be represented in the panel at the top of the dialog, displayed as a Near Bus and

Far Bus. If the Automatic Line Tap Dialog was opened by right-clicking a line on a oneline diagram, or by right-clicking

on a record in the case information display, the line will already be selected in the panel. You can change the line

selection by first choosing the Near Bus you desire, and then selecting the Far Bus from the list of possible

connections to the chosen Near Bus. Note that the percentage entered in the Position along line field will be in

relation to the selected Near Bus. The inserted bus and new sections of the tapped line will adhere to the following

settings:

Position along line

The field labeled Position along line will indicate the point where you right-clicked the mouse relative to the

location of the nearest of the two buses to the mouse-click in terms of a percentage of the total line length. In other

words, if the line is 10 units long, and you clicked the right mouse at location 7 units from one end of the line, the

Position along line will indicate 30% from the bus at the other end of the line, identified on the display as the Near

Bus. If you opened the Automatic Line Tap Dialog from the case information display or the Tools menu, the

Position along Line will be set to 50%. In either case, you can adjust this setting to place the new bus more

precisely. The placement of the new bus controls how the impedances of the new lines are set, as the impedance

of each section will equal the section’s corresponding percentage length multiplied by the impedance of the original

line. Note that the original charging capacitance of the line will be reassigned as determined by the selection under

the Shunt Model option.

New Bus Number

By default, Simulator will find and set an unused bus number for you, but you can specify the number to be used for

the new bus, between 1 and 99999. If you enter a bus number that already exists, you will be prompted to enter a

different number when you click the Tap button.

New Bus Name

Specify a name to be assigned to the new bus. By default this field is blank, and if left blank Simulator will set the

name of the bus the same as the new bus number.

New Bus Area

You can specify the area for the new bus to be the same as the Near Bus , the Far Bus , or another value of your

specification. If you select the Specify option, the edit box and find button will become enabled. You can then

enter an area number manually, or click Find to locate an area from the list of areas currently in the case. If you

want a new area to be assigned to the case for this bus, simply enter an unused area number manually in the box,

and Simulator will automatically set up the new area record for the case. You can then open the Area Information

Display and set the name and other values for the new area.

New Bus Zone

You can specify the zone for the new bus to be the same as the Near Bus, the Far Bus , or another zone of your

specification. If you select the Specify option, the edit box and find button will become enabled. You can then

enter a zone number manually, or click Find to locate a zone from the list of zones currently in the case. If you

want a new zone to be assigned to the case for this bus, simply enter an unused zone number manually in the box,

and Simulator will automatically set up the new zone record for the case. You can then open the Zone Information

Display and set the name and other values for the new Zone.

Shunt Model

By default, Simulator will reassign the original charging capacitance as line shunts at the original terminal bus ends

of the two new line segments. The charging capacitance of the two new branch elements will be set to 0. This will

result in an exact match of power flows before and after the line tap.

Alternatively, you can choose to have the capacitance converted approximately using percentage entered as the

Position along line. In other words, the original capacitance will be scaled and assigned to the two new segments

as charging capacitance. This will result in a slightly different power flow result after the line tap, as it is an

approximation of charging capacitance on the two new segments.

Treat sections as a multi-section line

Check the box labeled Treat sections as a multi-section line to force the status of the two new line sections to be

controlled in unison.

Click the Tap button to close the Automatic Line Tap Dialog and perform the line tap. If a value on the dialog is not set

properly, a warning message will appear, and you will need to either change the specified value or cancel the process.

178

Edit Mode Tools and Options

Setting Default Drawing Options

The Default Drawing Options Dialog is used to define the default sizes of new display objects, as well as various other

display parameters. These options are available only from Edit Mode. To open the Default Drawing Values Dialog,

select the menu option Options > Default Drawing Values in Edit Mode.

The Default Drawing Values Dialog is organized using tabs showing the types of objects that can be added to

onelines. Each type of object has a table which describes the defaults available for that object.

Generally, the Default Drawing Values apply when you insert new objects on an oneline diagram. Changing the

Default Drawing Values does not automatically affect the existing objects already drawn on the diagram. However,

you can select multiple objects on a oneline diagram, and right-click on any one object to invoke the object's popup

menu. You will find the option Apply Default Draw Values, which will modify the formatting of the selected objects to

meet the default drawing value specifications.

Variable Defaults depending on Voltage Level

Many kinds of objects can have more than one set of defaults specified depending on their voltage level. When

more than one set of defaults is specified, the table is always sorted by Nom KV.

A new object is inserted with properties corresponding to the default with the lowest Nom KV that the object's

nominal KV is larger than. If the object's nominal KV is smaller than all defaults, then it will be set according to the

default with the lowest nominal KV.

For instance, assume 4 sets of defaults are defined for buses roughly as follows

Nom KV

Size

>400

>300

>200

>100

A new bus with nominal voltage of 345 kV is inserted with size 10.

A new bus with nominal voltage of 299 kV is inserted with size 8.

A new bus with nominal voltage of 69 kV is inserted with size 5.

In order to add another set of defaults for a kind of object, right-click on the table and choose Insert from the local

menu. In order to delete a set of defaults, right-click on the table and choose Delete. Once you have inserted a

new default, specify the new Nom KV for the default along with the new defaults.

Notes: When you c hange the Nom KV of a default, the list always sorts itself according to Nom KV. Insert will not

be enabled in the local menu for objects that can not have more than one set of defaults. Delete will not be enabled

if only one set of defaults is defined.

Modifying Values in the Default Drawing Values Dialog

The font colors in tables of this dialog follow the conventions of the Case Information Displays. Most default values

are enterable and can be modified by selecting the value you want to change and then typing in the new value.

Other values are toggleable and can be changed by double-clicking on the value. For reference regarding what the

various "size" defaults mean, when the zoom level is at its nominal value (100%), the size of the screen is 100 by

100. There are also some special kinds of fields in this dialog which are discussed next.

Editing Colors and KV-Based Color Coding

In order to modify a color value, double-click on the colored rectangle to bring up the Color Dialog. Then specify the

color you want. For some defaults, such as fill color, it is possible to specify the default color to be "none". In order

to set a color default to "none", select the colored rectangle and press the Delete key.

At times, a user may want to see the kV level of screen objects directly from the oneline diagam, without having to

open a text display. One way to do this is to color code the elements on the oneline diagram according to kV level.

Right-click on the table and choose Insert from the local menu. Specify the Nom kV and color.

Editing Default Field Positions ("Pos1", "Pos2", etc…)

Many objects allow you to specify some default fields to be automatically added when a new object is drawn. For

example, you may want to insert the bus name next to all new Bus Objects. In order to specify these defaults, click

on the table row corresponding to defaults you are interested in. Then click on the Show Field Positions button.

This brings up the Positions for Adding New Fields Dialog and will show you the present settings for new fields.

Positions that have a default specified will be highlights and the name of the default field will be shown. Positions

with no default field will not be highlighted and will say "Pos1", "Pos2", etc…. For objects that have more than one

possible orientation (e.g. generators can be up, right, left or down), the Adding New Fields Dialog will show

positions for each orientation.

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In order to modify the settings, move your mouse over the position on the dialog you want to change and click. This

will bring up the appropriate Field Options Dialog such as the Bus Field Options, Generator Field Options, Load

Field Options, Switched Shunt Field Options, Line Field Options, Interface Field Options, Substation Field Options,

Area Field Options, Super Area Field Options, or the Zone Field Options. Simply select the field you want and

choose OK. If you would like to set a default field to "none", click Remove Field instead of OK. You can also

modify default fields by double-clicking on the table for "Pos1", "Pos2", etc… This brings up the appropriate Field

Options Dialog as well. If you press the Delete key while on a "Pos" field in the table, it will set the default field to

"none".

Note that as you navigate through the tabs on this Default Drawing Values Dialog, the Positions for Adding New

Fields Dialog will update to show you the default for the present object and voltage level you have selected.

Editing Stub Size and Stub Space

When utilizing the Automatically Insert Transmission Lines feature, the Stub Size and Stub Space values are used.

Simulator will draw each automatically inserted branch such that it emerges from both its terminal buses at right

angles. To accomplish this, Simulator draws each automatically inserted branch in three segments: two stubs

perpendicular to the terminal buses having a length specified by the value supplied for Stub Size, and a third

segment joining the two stubs. The amount of space between lines as the converge into a bus is set by Stub

Space .

If you do not want transmission line stubs to be inserted, then set Stub Size to 'none' or to a negative number. Note

in order to set a value for Stub Space , Stub Size must be set to a positive number first.

Editing CB Size

When you insert new transmission lines or transformers, circuit breakers will automatically be inserted on the

branch with their size specified by CB Size. If you do not want Circuit Breakers inserted for a particular voltage

level, then set CB Size to 'none' or a negative number.

Editing Pie Size

When you insert new transmission lines or transformers, pie charts will automatically be inserted on the branch with

their size specified by Pie Size. If you do not want pie charts inserted for a particular voltage level, then set Pie Size

to 'none' or a negative number.

Set Default Font

Click on this button to set the default font used for new text fields. This is the font which will be used for all new text

fields. Note however that the default font size set using this dialog is not used unless the option Use the default

font size for new text objects is selected. Otherwise, the specific kind of object and voltage level specifies what

the font size should be. For example, in the Interface tab, one of the defaults is Font Size. New Interface Fields will

use this font size.

Only Cut/Copy Display Objects, Not Power System Records

When you cut or delete an object from the oneline, Simulator needs to know whether you simply want to delete the

display object from the oneline or to purge the definition of the power system object from the model. Check this box

to tell Simulator to assume that it should always delete objects just from the oneline display, not from the power

system model.

Oneline / Bus View Background Color

To change the default oneline background color, click on the Change button to select a new color. This color

applies to both new oneline diagrams and the background color of the bus view oneline diagram.

180

Edit Mode Tools and Options

Bus Selection Page

The Bus Selection page is currently used with two displays:

The Equivalencing Display, to partition the system into the study subsystem ("Study") and the external

subsystem ("External").

The Facility Analysis Dialog, to determine the buses in the external subsystem from which the buses in the

facility would be isolated.

The following description concerns the Equivalencing Display, but the functionality of the Bus Selection Page is similar

for both applications.

Buses, Areas, and Zones lists

For both equivalencing and facility analysis, use these lists to manually change the system designation of individual

buses, areas, or zones. Note that changing the system designation on the area or zone tab is jus t another form of

changing the designation of study / external system of individual buses. Click on the Which System field in each of

these tables to toggle the object’s affiliation with the study or external systems, subject to the values of the Filter by

kV option and the Neighbor Tiers field.

In addition, the bus selection table for facility analysis contains one additional column labeled Selected. This Yes

or No field indicates which buses in the Study system belong to the Facility being analyzed. Double-clicking one of

the fields in this column will toggle the value of the field between Yes or No.

External

Use these fields to specify a range of areas, zones, or buses to be added to the external system. The Filter by kV

and Neighbor Tiers controls will also shape the selection of buses to add to the external system.

Study

Use these fields to specify a range of areas, zones, or buses to be added to the study system. The Filter by kV and

Neighbor Tiers controls will also shape the selection of buses to add to the study system.

Include how many tiers of neighbors?

This value indicates the number of tiers of neighbors to carry with each selected bus when adding the selected bus

to either the study or external system. For example, if Neighbor Tiers is 1 and we elect to add bus X to the external

system, both bus X and its first tier of neighbors will be added to the external system. If Neighbor Tiers is 0, only

bus X will be added to the external system.

Filter by kV

If the Filter by kV box is checked, then only buses having a nominal voltage level between the values given in the

Max kV and Min kV fields can be selected.

Set All As External

Click this button to assign all buses to the external system.

Set Branch Terminals External or Study

Clicking either of these two buttons allows setting advanced filter criteria which define a branch or group of

branches. Once the criteria are set, clicking Filter will select the terminal buses of all branches meeting the filter

criteria, and set those buses to either the External or Study system, depending on which button was pressed.

Select Buses using a Network Cut

A custom network cut can be defined for choosing which buses should remain in either the Study or External

system.

Save Buses to File

Once the system has been partitioned, this command allows you to store the numbers of the buses of the study

system in a text file.

Load Buses from File

Click on this button to load a listing of the buses to be included in the study system from a text file. You will be

prompted to select the text file. The format of this text file is such that one bus number occupies each line. Any

buses not identified in this file are defined as being in the external system.

Example

Assume you would like to create an equivalent containing all the buses in areas 1-5 and 10, plus any tie buses, and

bus number 2050.

Since initially all buses are in the study system, first enter 1-1000 in the Areas field of Add to External

System. Since the area of every bus is within this range, this places all the buses in the external system.

Alternatively, click Set All As External to accomplish the same objective.

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Edit Mode Tools and Options

List Unlinked Display Objects

An unlinked object is a display object not linked to a record in the power system model (model object). The existence

of unlinked display objects on a oneline diagram can be misleading because they have zero flows and zero bus

voltages associated with them. See Object Relationships for more information.

Select Options > List Display Objects > Unlinked from the main menu in Edit Mode to identify unlinked objects.

Unlinked Display Objects Dialog

Total Number of Unlinked Display Objects

Indicates the total number of unlinked objects on the display. Ideally, this number should be zero. If nonzero, the

unlinked objects are identified in the table by type, screen location, and zoom range over which the object is visible.

Delete Unlinked Objects

Click on this button to permanently remove all unlinked objects from the display. Exercise this option carefully.

Generally, you will want to do this either when you have substantially modified a power flow case, such as by

creating an equivalent, or when you are using the oneline with a new power system case.

View Options for Highlighting Unlinked Objects on the Oneline

Click on this button will open the Grid/Highlight Unlinked Objects tab of the Oneline Display Options Dialog.

Type, X/Y Location

The remainder of the display shows the type, location, identification, layer, applicable zoom level, anchored

property, and font size for each unlinked object. This table is a type of Case Information Display and thus behaves

similarly to all other case information displays. Right-click on a record in this table to invoke the local menu. Select

Pan Oneline to Object to locate and select the unlinked object on the oneline diagram.

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PowerWorld Simulator version 11. Manual - page 5