PowerWorld Simulator version 11. Manual

Creating, Loading, and Saving Simulator Cases

Delta - Wye

Grounded Wye - Delta

Delta - Grounded Wye

Delta - Delta

Switched Shunt

SSHUNT busnum numblocks Bzer1 Bzer2 …

where

busnum

terminal bus number,

numblocks

number of different zero sequence admittance blocks,

Bzer#

zero sequence susceptance for each admittance block, maximum of 8.

Mutual Impedance

MUTIMP from1 to1 ckt1 from2 to2 ckt2 RM XM start1 end1 start2 end2

where

from1, to1

from and to bus numbers of the first mutually coupled branch,

ckt1

circuit identifier of the first mutually coupled branch,

from2, to2

from and to bus numbers of the second mutually coupled branch,

ckt2

circuit identifier of the second mutually coupled branch,

RM, XM

zero sequence mutual resistance and reactance,

start1, end1

start and end locations of the section of the first line affected by the mutual

coupling, with each point represented as a percentage of the total line length

(between 0 and 1),

start2, end2

start and end locations of the section of the second line affected by the mutual

coupling, with each point represented as a percentage of the total line length

(betw een 0 and 1).

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Creating, Loading, and Saving Simulator Cases

Saving Images as Jpegs

Simulator can save oneline diagrams, bus view displays, and strip charts as jpeg images. To save a oneline diagram

or bus view display as a jpeg, select File > Export Oneline from the main menu. This brings up the save file dialog

where y ou can specify file type from the dropdown menu. Choose jpeg, type the file name, and press save. This

brings up the resolution screen where you decide the picture's resolution. Adjust the resolution control to specify the

compression ratio at which to save the diagram as a jpeg. The greater the resolution you specify, the larger the

resulting file will be. Click Save to save the image or click Cancel to terminate the process without saving the image

as a jpeg.

To save a strip chart as a jpeg image, right-click on the background of the strip chart and select Save As Jpeg from

the resulting local menu. Specify the compression/resolution in the Jpeg Options Dialog. Click Cancel to terminate

the process, or click Save to save the jpeg to a file whose name you specify.

105

Saving Admittance Matrix and Jacobian Information

The Save Ybus or Power Flow Jacobian Dialog is used to store the power system bus admittance matrix (Ybus)

and/or the power f low Jacobian in a text format that can be easily read into other programs such as MATLAB“. This

dialog is primarily designed for users doing power system analysis research. The dialog has the following fields.

Ybus in MATLAB Format

Filename for Saving Ybus

Enter the name of the file in which to store the Ybus data. The Ybus data is stored using the MATLAB sparse

matrix format in the matrix Ybus . If the Include Bus Voltages field is checked, then the bus voltages are also

stored, but in the vector V.

Save Ybus in MATLAB Format

Click this button to save the Ybus.

Power Flow Jacobian in MATLAB Format

Jacobian Save File

Enter the name of the file in which to store Jacobian data. The Jacobian is stored using the MATLAB sparse matrix

format in the matrix Jac.

Jacobian ID Save File

Enter the filename to store the text identifier information. This information is used to translate the bus numbering

convention used in the Jacobian and Ybus files with the actual bus number and name in the case.

File Type

Choose the type of MATLAB file you wish to save as. The MATLAB .M Format is the more common text format

used for directly loading MATLAB information. The Text for MATLAB Ascii is for use with MATLAB’s ability to

read Ascii files. The Ascii file type can be read into MATLAB much faster than the traditional .M files.

Jacobian Form

Select Rectangular to store the rectangular form of the Jacobian, or Polar to store the polar form of the Jacobian.

Save Jacobian

Click this button to save the Jacobian and object identifier information.

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Overview

Edit Mode Overview

The Edit Mode is used to create and/or modify cases and onelines. You can use the Edit Mode to create a case from

scratch or to modify existing power flow cases stored in PowerWorld PWB or AUX files, in the PTI Raw data format,

GE PSLF EPC data format, or the IEEE Common Format. New users may wish to view step-by-step tutorials on either

Creating a New Case from Scratch

Creating Onelines for an Existing Power Flow Case.

To enter the Edit Mode, select the Edit Mode button on the Program Toolbar, or choose File > Switch to Edit Mode

(will only be visible if you are in Run Mode) from the file menu.

A powerful capability of the Simulator is its ability to create or modify a case by graphically placing/editing display

objects on a oneline diagram. These display objects consist of both power system devices, such as buses,

generators, and transmission lines; and additional objects that show various system parameters, provide descriptive

text, or function as a static background.

Simulator’s oneline diagrams illustrate the current state of the components of the power system. Most display objects

correspond to records in the underlying power system model, but not all records in the power system model need to

have an associated display object. In fact, for large system models, it may be that most of the system will not be

illustrated. In such cases, you will want to devote more detail to the more critical areas of the system so as not to

clutter the view. Furthermore, it is possible to associate more than one oneline with a single power flow case, and a

single oneline may be associated with multiple cases. This great flexibility can prove to be a big time-saver. Please

see Relationship Between Display Objects and the Power System Model for a more thorough discussion.

108

Building a Oneline Diagram

Edit Mode General Procedures

In order to simplify the process of graphically constructing a power flow case, Simulator’s drawing interface obeys the

following conventions for most objects:

Inserting a New Object

· Select the type of the object you wish to add from the Insert MenuInsert_Menu<+>.

· Left-click on the location on the display where you would like to position the object.

· Once the object is placed, Simulator displays a dialog box that allows you to specify various options for the object.

· If desired, use the Format Menu to change the appearance of the object once it has been placed.

Moving or Resizing an Existing Object

· Select the object by clicking on the object with the left mouse button. Handles are displayed around the object to

indicate it has been selected.

· To move the position of the object, place the mouse anywhere on the object except at a handle location. Then drag

the object around the screen by holding the left mouse button down.

· To change the size of an object using the mouse, first select the object. Then place the mouse on one of the

object’s resizing handles. The cursor will change to either a horizontal, vertical or diagonal two-headed arrow

shape. Then drag the mouse to change the object’s size. Text/field objects cannot be resized; rather, you should

change their font size. You can also specify the size of most objects using their dialog boxes.

Viewing/Modifying Object Parameters

· To view and/or change the options associated with an object, right-click on the object. This either displays the

object’s dialog box directly, or it display’s the objects local menu, from which you can elect to see the object’s dialog

box.

Selecting Several Objects to Modify Their Appearance

Hold down the Shift key while clicking objects on the screen to select several objects at once. You may then

change the objects’ attributes, such as Font, Line/Fill, etc., by choosing Display/Size from the Format Menu. To

move the objects that are selected, click and hold down the left mouse button on any of the selected objects, drag

the selected objects to a new location, and release the mouse button to place them.

To select a set of objects that meet some given criteria, choose Select by Criteria from the Edit Menu. As an

example, you can use Select By Criteria to select all the 345 kV transmission lines in a case.

You can also use the Rectangle Selector button on the Edit Toolbar to select all objects in a particular region of the

oneline.

Changing An Object’s Screen Appearance

Use the Format Menu to change the screen appearance of either a selection of objects or the entire display.

109

Anchored Objects

While in Edit Mode, Simulator allows certain objects to be attached, or anchored, to another object, called the anchor.

When an object that functions as an anchor is moved, all objects that are anchored to it will move with it. This feature

can be very useful when you move objects around the oneline diagram in Edit Mode.

Anchoring has the property of "stacking" in Simulator. In other words, one object is anchored to another, which is in

turn anchored to yet another. The best way to describe this is by example. A generator text field can be anchored to

a generator. The generator, in turn, can be anchored to its terminal bus. If you move the terminal bus, both the

generator and its anchored fields also move with the bus. However, if you just move the generator itself, only the

generator fields will move with it. The bus and all other objects anchored directly to the bus remain in their original

location.

There are several types of anchored objects:

Buses

Loads, generators, switched shunts, bus fields, interfaces, transformers, transmission lines and voltage gauges may

be anchored to their associated bus. When the anchor bus is moved, these anchored objects will move with it.

Substations

Similar to buses, any loads, generators, switched shunts, substation fields, interfaces, transformers, and

transmission lines may be anchored to their associated buses. When the anchor substation is moved, these

anchored objects will move with it.

Generators

Generator fields may be anchored to their associated generator. When the anchor generator is moved, these

anchored objects will move with it.

Loads

Load fields may be anchored to their associated load. When the anchor load is moved, these anchored objects will

move with it.

Switched Shunts

Switched shunt fields may be anchored to their associated switched shunt. When the anchor switched shunt is

moved, these anchored objects will move with it.

Area/Zone Objects

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

Lines and Transformers

Circuit breakers, line flow pie charts, and line analogs may be anchored to their associated line/transformer. When

the line/transformer is moved, these anchored objects will move with it.

Interfaces

Interface fields and interface pie charts can be anchored to their associated interface.

112

Building a Oneline Diagram

Inserting and Placing Multiple Display Fields

Simulator provides a convenient method of adding display fields to a variety of oneline display objects and placing

them in default positions relative to the display object. Unlike the field placement implemented by selecting Insert >

Fields from the main menu, the method described here allows you to place multiple fields around a display object in a

single operation. This option is available for several different types of objects, including buses, generators, lines and

transformers, shunts, and loads. The option can always be accessed by right clicking the display object of interest and

selecting the Add New Fields to … option from the resulting local menu. This brings up the Insert New Fields

around Selected Objects Dialog. This dialog is divided into several tabs by object type. Only tabs that correspond

to the type of objects you have selected will be available.

The tabs for inserting and placing multiple display fields for the various display objects (buses, generators,

lines/transformers, shunts, and loads) are virtually identical in content. The tab illustrates the possible locations of the

display fields for the various orientations of the display object. For example, since buses may be oriented either

horizontally or vertically, the dialog shows how each of the eight possible bus fields would be positioned for each of the

two orientations. Generators, loads, and shunts each hav e four possible orientations, so the dialog identifies the

locations for the possible fields for each of the four orientations. Transmission lines and transformers can assume

only one orientation, and the dialog will thus show the possible field locations for that single orientation.

Each field location is identified on the illustrations with a label of the form Pos #. 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, or the Line 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.

Click OK to implement your choices for field additions and placement, or click Cancel to discard the changes.

This help topic has gone over how to add new fields to existing display objects. It should be noted from this discussion

that all objects have an associated set of default fields that will be added to the oneline when the objects are originally

inserted. You may redefine the default fields selecting Options > Default Drawing Values from the main menu and

modifying the Default Drawing Options Dialog.

113

Areas, Zones and Owners

Area/Zone/Super Area Display Objects

Areas and zones may be represented on Simulator oneline diagrams. This feature may prove particularly useful for

illustrating how the areas and zones comprising the system are interconnected. Not only can Simulator depict bus-to-

bus connections, but it can also show area-to-area and zone-to-zone connections through the use of area and zone

display objects and interface objects. Since multiple oneline diagrams can be associated with a single power flow

case, you may find it useful to construct two oneline diagrams for your model: one showing the system at the bus

level, and the other representing the areas or zones that make up the model as blocks tied together by area-area or

zone-zone interface objects.

Edit Mode

To add an area or zone display object to a oneline, choose Insert > Area/Zone/Super Area from the main menu or

click the Area/Zone button on the Insert Toolbar. Then, click the left mouse on the oneline to indicate where you

would like to place the new area or zone object. The Area/Zone/Super Area Display Options Dialog will appear.

Supply the requested information and click OK to finish adding the area or zone or Cancel to abort the operation. If

you choose OK, the new area or zone display object will appear on the oneline diagram at the location you chose.

When you select an area or zone display object, it will display its sizing handles. Use the sizing handles to resize

the area or zone display object as desired.

Area or zone objects may be connected together by interface objects.

It is important to note that this discussion covers how to add area or zone display objects only, not area or zone

records. Area or zone records cannot be added graphically. Instead, area or zone records are added to the model

whenever a bus is assigned to an area or zone that does not already exist. The procedure we have discussed here

can be used only to represent a pre-existing area or zone graphically on a oneline. It cannot be used to add an

area or zone to a case model.

114

Building a Oneline Diagram

Area/Zone/Super Area Display Options Dialog

When you insert an area or zone display object on a oneline diagram, Simulator opens the Area/Zone/Super Area

Display Options dialog. This dialog is used to control various display and identity attributes of the area or zone display

object. The dialog contains the following fields:

Number

This dropdown box lists the number of all areas (if you are inserting an area object), zones (if you are inserting a

zone object), or super areas (if you are inserting a super area object) in the case. Use this control to associate the

display object with the correct area, zone, or super area.

Name

If you would prefer to search through areas, zones, and super areas by name rather than by number, use the Name

dropdown box to see a list of names of all the areas or zones in the case.

Show Record Type Prefix

Check this box if you wish to place the prefix Area, Zone or Super Area before the name/number caption in the

object.

Prefix Text

Specify additional prefix text to be added before the Record Type prefix.

The remainder of the choices presented on the Area/Zone/Super Area Display Options dialog pertain to the object's

display appearance.

Style

Choose whether the display object should appear as a rectangle or as an ellipse.

Caption

Indicate how the display object should be identified to the user: by name, number, or both.

Width, Height

The dimensions of the new display object.

Click OK to save your selections and add the object to the oneline, or choose Cancel to terminate the addition.

115

Area Fields on Onelines

Area fields are used to show various values associated with a particular area of the power system. Right clicking on

the area field displays the Area Field Dialog.

Edit Mode

To enter a new area field, first select Insert > Fields > Area Fields from the main menu, or click the Area Fields

button on the Insert Toolbar. Then, click on or near a bus in the area for which you want to add a field. This calls up

the Area Field Dialog. Verify that the area number is correct. By default, this value is the number of the area

associated with the closest bus. Enter the total number of digits the field should display as well as the number of

digits to the right of the decimal point. Depending on what the field is designed to display, you may need to enter an

additional area number. Finally, select the field type. Click OK to save the field or Cancel to abort the operation.

To modify the parameters of an existing area field, position the cursor anywhere on the area field and right-click.

This again brings up the Area Field Dialog. Use the Format > Display / Zoom Levels main menu option to change

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

> Oneline Display > Default Font option to change the font for all fields on the display.

118

Building a Oneline Diagram

Zone Fields on Onelines

Zone field objects are used to show different values associated with zones and the system. This dialog is used to view

and modify the parameters associated with these fields. Note that the zone number itself cannot be changed on this

dialog. To reach this dialog, go to Insert > Field > Zone Field in Edit Mode.

Zone Number

Zone number associated with the field. When you insert fields graphically, this field is automatically set to the zone

number associated with the closest bus on the oneline. With most types of zone fields, an Zone Number of 0 is

valid and defines the field as showing values for the entire system.

Find…

If you do not know the exact zone number you are looking for, you can click this button to open the advanced

search engine.

Total Digits in Fields

Total number of digits to show in the field.

Digits to Right of Decimal

Number of digits to show to the right of the decimal point.

Other Zone Number

Some of the fields, such as MW Flow to Other Zone , require that a second area be specified. If applicable, enter

the second (other) zone here.

Delta per Mouse Click

This value is used only with the Sched Flow to Other Zone field type. When there is a nonzero entry in this field,

and the field type is Sched Flow to Other Zone , a spin button is shown to the right of the zone field. When the up

spin button is clicked, the flow to the other zone is increased by this number of MW; when the down button is

clicked, the scheduled flow is decreased by this amount.

Field Value

Shows the current output for the zone field. Whenever you change the Type of Field selection, this field is

updated.

For the Sched Flow to Other Zone field type only, you can specify a new value in MW. Exports are assumed to be

positive.

Field Prefix

An optional string that precedes the field value.

Rotation Angle in Degrees

The angle at which the text is to appear on the oneline diagram.

Include Suffix

If the Include Suffix checkbox is checked, the corresponding field units will be displayed after the current value.

Otherwise, only the value without units will be shown.

Type of Field

Used to determine the type of zone field to show. The two choices available are Name and Number.

Name

Zone name (eight characters maximum). The Zone Number field must correspond to a valid zone.

Number

Zone number (1 - 999). The Zone Number field must correspond to a valid area.

MW Load, Mvar Load

If the zone number is nonzero, then these fields show Total MW or Mvar load for the zone. If the zone number is

zero, these fields show the total load in the entire system.

MW Generation, Mvar Generation

If the Zone Number is nonzero, then these fields show Total MW or Mvar generation for the zone. If the Zone

Number is zero, these fields show the total generation in the entire system.

MW Shunts, MVR Shunts

If the Zone Number is nonzero, then these fields show Total MW or Mvar shunt compensation for the zone. If the

Zone Number is zero, these fields show the total shunt compensation in the entire system.

119

Owner Fields on Onelines

Owner field objects are used to show different values associated with owners. This dialog is used to view and modify

the parameters associated with these fields. To insert an Owner field, click on Insert > Field > Owner Field from the

main menu.

Owner Number

Owner number associated with the field. When you insert fields graphically, this field is automatically set to the

owner number associated with the closest bus on the oneline.

Find by Number

To switch to a different owner in the field options dialog, you can enter the number in the Owner Number field, and

press the Find by Number button to update the dialog with information for the new owner.

Owner Name

Name of the owner whose information is presently being displayed in the dialog.

Find by Name

To switch to a different owner in the field options dialog, you can enter the name in the Owner Name field, and

press the Find by Name button to update the dialog with information for the new owner.

Total Digits in Fields

Total number of digits to show in the field.

Digits to Right of Decimal

Number of digits to show to the right of the decimal point.

Field Prefix

An optional string that precedes the field value.

Rotation Angle in Degrees

The angle at which the text is to appear on the oneline diagram.

Field Value

Shows the current output for the owner field. Whenever you change the Type of Field selection, this field is

updated.

Include Suffix

If the Include Suffix checkbox is checked, the corresponding field units will be displayed after the current value.

Otherwise, only the value without units will be shown.

Type of Field

Used to determine the type of owner field to show. You can choose from one of the six default fields, or click on the

Find Field… button to choose from a list of all available owner fields.

122

Building a Oneline Diagram

Buses

Bus Display Objects

In power system analysis, the term "bus" is used to refer to the point where a number of electrical devices, such as

lines, loads or generators, join together. On the oneline diagram, buses are usually represented with either a thick

horizontal line or a thick vertical line. The bus thickness and color can be customized.

Right-clicking on the bus will display its local menu. The local menu offers you the chance to view the corresponding

Bus Dialog, the Quick Power Flow List, and the Bus View Display. When the application is in Edit Mode, the local

menu will also allow you to add bus fields to the bus and to insert any undrawn buses connected to the selected bus.

Bus Fields are often placed close to the bus to indicate its voltage magnitude, voltage angle, and other relevant

information.

Edit Mode

To add a new bus to the case, follow this simple procedure:

· Select Insert > Bus from the main menu, or select the Bus button on the Insert Toolbar. This prepares

Simulator to insert a new bus.

· Left-click on the oneline background at the location where you want to plac e the new bus. This invokes the Bus

Option Dialog.

· Use the Bus Option Dialog Box to specify the number, name, size, thickness, orientation, area, zone, and

nominal voltage of the bus, as well as the load and shunt compensation connected to it. Every bus must have

a unique number.

· Click OK on the Bus Option Dialog to finish creating the bus and to close the dialog. If you do not wish to add

the bus to the case, click Cancel.

If you are simply adding a symbol to the oneline diagram for a bus that has already been defined in the case, many

of the parameters you are asked to specify in step three will be filled in for you.

To modify the parameters for an existing bus, position the cursor on the bus and right-click to invoke the bus' local

menu. From the local menu, choose Bus Information Dialog to view the associated Bus Dialog. You may change

any of the parameters specified there. When a bus' number is changed, the bus numbers associated with all of the

devices attached to that bus are also automatically changed. To renumber a number of buses simultaneously,

please see Options, Bus Renumbering Dialog.

To modify any aspect of a bus' appearance, first select the bus, and then click Format > Display/Size from the

main menu. You can change the length of the bus (but not its thickness) by dragging the bus' resizing handles.

To delete an existing bus, use either the Edit > Cut command to preserve a copy of the bus on the Windows

clipboard, or Edit > Delete to remove the bus without copying it to the clipboard. You will be asked whether you

want to remove both the display object and its associated bus record, or merely the display object, leaving the bus

in the power flow model. If you will never be deleting a record from the power system model, you may also choose

the option labeled Always Delete Objects Only. Be careful when deleting existing buses with attached devices. An

error will occur during validation if you do not also delete the attached devices or attach them to other buses.

123

Bus Fields on Onelines

Bus field objects are used primarily to indicate various quantities associated with bus devices. Furthermore, some bus

field types, which are distinguished by an integrated spin button, may be used to change bus device properties.

Run Mode

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

associated field.

Right clicking on a bus field gives you the option to open the Bus Field Dialog or the Bus Information Dialog.

Edit Mode

Simulator offers two options for adding bus 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 > Bus Field from the main menu or the Bus Field button from

the Insert Toolbar and then select the bus to which you want to add the field. This invokes the Bus Field Dialog.

Enter the bus number associated with the device (the default is the closest bus to the field), the total number of

digits to show, and the number of digits to the right of the decimal point. Specify the ID field when working with

fields related to generators or loads. Next, select the type of field to show. To show load/capacitor/generator

values, the corresponding device must, of course, be attached to the bus. The Setpoint Generator MW type should

be selected only for cases that employ the uniform frequency option. For generator actual MW and Setpoint MW

types and load MW and Mvar fields, specify a nonzero value in the Delta per Mouse Click to design a bus field with

an integrated spin control. The Gen AGC Status field is used to display the automatic generation control status of

the generator. The user can toggle this status in Simulator by clicking on the field. Likewise, the Gen AVR Status

field is used to display the automatic voltage regulation status of the generator. Again the user can toggle this

status by clicking on the field.

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

Bus from the resulting local menu. Please see Inserting and Placing Multiple Display Fields for more details.

To modify the parameters of an existing bus field, position the cursor anywhere on the object and right-click. This

brings up the Bus Field Dialog. Choose Font, Line/Fill, or Display/Size from the Format menu to change various

display attributes of the field, including its font and background color.

124

Building a Oneline Diagram

Voltage Gauges

Voltage gauges provide a way to visualize the voltage of a bus relative to its high- and low -voltage alarm limits. A

gauge looks very much like a thermometer. As the temperature changes, the height of the mercury in the

thermometer moves up and down. One reads the temperature measured by the thermometer by noting the marking

that matches the top of the mercury. Voltage gauges in Simulator work the same way. A voltage gauge has three

markings on its side, eac h of which identifies a key per-unit voltage level. Specifically, these three markings locate the

minimum, maximum, and target per-unit voltages. Often, the target voltage level is the nominal voltage, but this is not

a requirement. Inside the gauge is a filled region. The default color of the filled region is blue, but this can be

changed. When you create the voltage gauge, you associate it with a bus, and you specify its fill color and its

minimum, maximum, and target voltage levels. Once the gauge has been placed on a display, it will reveal changes in

its associated bus’s voltage by varying the height of its filled region. This tool was introduced to provide an alternative

to voltage contours to show the variation of voltage across a region. Contouring can reveal the variation of only a

single quantity at a time. For example, it is impossible to contour bus voltage magnitude and bus voltage phase angle

simultaneously. Voltage gauges are helpful because they allow you to show the voltage profile superimposed on a

contour of some other quantity.

To add a voltage gauge to a display, switch to Edit Mode and select Insert > Gauges > Bus from the main menu.

The cursor will become a crosshairs. Click on the oneline diagram where you would like the new voltage gauge to

appear. The Voltage Gauge Options Dialog will appear. Use this dialog to define the minimum, maximum and target

voltages for the voltage gauge, as well as its fill color and whether it should be anchored to its associated bus. After

you click the "OK" button, the Voltage Gauge Options Dialog will close, and the new voltage gauge will appear.

Once a gauge has been placed on the oneline, the height of its filled region will change as the voltage of its associated

bus changes. To modify any of the characteristics of the gauge, such as its key voltage levels, fill color, and anchor

setting, simply right-click on the bus voltage gauge to open the Voltage Gauge Options Dialog again.

125

Voltage Gauge Options Dialog

The Voltage Gauge Options Dialog is used to define and configure a bus voltage gauge. A bus voltage gauge is

associated with a particular bus and reveals the bus’s voltage relative to specified minimum, maximum, and target per-

unit voltage levels. The height of the colored column in the voltage gauge indicates the bus’s voltage relative to these

markings.

The dialog sports the following controls:

Number, Name, and Find

Use the Number and Name dropdown boxes to identify the bus to which you want the gauge to correspond. Select

a bus number from the Number dropdown box to identify the bus by number, and a bus name from the Name

dropdown box to identify a bus by name. It may be more convenient to press the Find to open the Find Dialog,

which allows you to spec ify a bus by either name or number using wildcards. When you first open the Bus Voltage

Gauge Dialog, the bus name and number will correspond to the bus object that was closest to the point where you

clicked.

Minimum, Target, and Maximum

Use these three spin edit boxes in the Voltage levels group box to specify the minimum, maximum, and target per-

unit voltage levels. These settings determine where on the gauge its three markings will be drawn.

The Minimum and Maximum value will be taken from the Limit Monitoring settings for the current bus, unless you

uncheck the option "Set Limits According to Current Limit Monitoring Settings ".

Fill color

The Fill color box reveals the color that will be used to paint the filled region of the gauge. Click on the Fill color box

to open a Color Dialog, which you may then use to specify a different color.

Anchored

A bus voltage gauge is said to be anchored if, when you move its associated bus object, it moves with it. Check the

Anchored check box to ensure that the gauge wll move with its associated bus. Otherwise, when you move its

associated bus object, the gauge will stay in its current position.

OK, Help, and Cancel

Click OK to finalize your settings. This will create a new voltage gauge object if you are trying to create one from

scratch, or it will modify the appearance and settings of an existing one if you have chosen to modify one that has

already been defined. Click Cancel to dispose of your changes. Click the Help button to reveal this help text.

126

Building a Oneline Diagram

Substations

Substation Display Objects

Substations in Simulator define a group of buses that are closely connected. Each bus can belong to either one

substation or no substation (called unassigned). By default in Simulator, all buses are not assigned to a substation.

This is done because all traditional text file power flow formats do not include information regarding a bus' substation.

Substations are represented on the oneline as a rectangle with the name of the substation inside it. Other information

about the substation is also displayed on the rectangle:

· The upper left corner displays a generator symbol if generation exists in the substation.

· The upper right corner displays a load symbol if load exists in the substation.

· The lower right corner displays a shunt symbol if shunts exist in the substation.

· The lower left corner displays the number of buses inside the substation.

· The lower middle displays the maximum voltage level in the substation.

You can also customize the size, colors, and font name and style of a substation object. Note however that the font

size of the substation object is automatically changed by Simulator as you change the size of the rectangle.

Right-clicking on the substation will display its local menu. The local menu offers you the chance to view the

corresponding Substation Information Dialog and the Substation View Display.

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Building a Oneline Diagram

Generators

Generator Display Objects

Generators are represented on the oneline as circles with a "dog bone" rotor inside. Multiple generators at a bus are

allowed, with each being distinguished by a unique character identifier.

Each generator symbol (except that corresponding to the slack) is equipped with a circuit breaker that can be used to

change the status of the generator. You may toggle the generator status by clicking on the circuit breaker.

Furthermore, the angular position of the dog bone rotor can indicate the "angle" of the voltage at the generator

terminal if desired.

Generator fields are often placed close to the generator on the oneline to indicate the generator's MW/Mvar output.

Run Mode

When animation is active, the default flow of the arrows emerging from the generator is proportional to its MW

output. You can customize the appearance of this flow using the Animated Flows Tab of the Oneline Display

Options Dialog.

Right clicking on the generator brings up the generator submenu. This menu is used to display a variety of

information about the generator, including

· Generator Information Dialog

· Input-output curve

· Fuel cost curve

· Incremental cost curve

· Heat-rate curve

· Reactive capability curve

Edit Mode

To add a new generator to the case, select Insert > Generator from the main menu, or click the Generator button

on the Insert Toolbar. Then, place the cursor on the bus where you would like to attach the generator, and click

with the left mouse button. This calls up the Generator Dialog. The bus number is automatically determined from

the bus to which you attached the generator. The ID field contains a an alphanumeric ID used to distinguish

multiple generators at a bus. The default is '1'.

Enter the size, the thickness of the lines (in pixels) used to display the device, orientation, and other parameters for

the generator. Each generator automatically contains a switch for connecting or disconnecting the device in

Simulator. Select OK to add the generator. If you do not want to add the generator to the case, select Cancel.

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

brings up the Generator Dialog. You can then change any parameter (be careful in renumbering an existing

generator). Use the Format Menu commands to change the color, line thickness, and other display parameters.

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Generator Fields on Onelines

Generator field objects are used primarily to indicate various quantities associated with generation devices.

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

generation device properties.

Run Mode

For generator 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 Generator Field Dialog or the Generator

Information Dialog.

Edit Mode

Simulator offers two options for adding generator 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 > Generator Field from the main menu or the

Generator Field button from the Insert Toolbar and click near generator for which you want to add the field. This

invokes the Generator Field Dialog. Enter the bus number associated with the device (the default is the bus

associated to the closest generator 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 Setpoint Generator MW type

should be selected only for cases that employ the uniform frequency option. For generator actual MW and Setpoint

MW types and load MW and Mvar fields, specify a nonzero value in the Delta per Mouse Click to design a bus field

with an integrated spin control. The Gen AGC Status field is used to display the automatic generation control status

of the generator. The user can toggle this status in Simulator by clicking on the field. Likewise, the Gen AVR

Status field is used to display the automatic voltage regulation status of the generator. Again the user can toggle

this status by clicking on the field.

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

Around Generator from the resulting local menu. Please see Inserting and Placing Multiple Display Fields for more

details.

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

This brings up the Generator Field Dialog. Choose Font, Line/Fill, or 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

Loads

Load Display Objects

Simulator models aggregate load at each system bus. Multiple loads at a bus are allowed. Each load object on the

oneline comes equipped with a circuit breaker. The status of the load corresponds to the status of its circuit breaker. A

circuit breaker is closed if it appears as a filled red square, and it is open if it appears as a green square outline. In

Run Mode, you may toggle the status of the load by clicking on its associated circuit breaker.

Load fields are often placed close to the loads on the oneline to indicate their MW/Mvar value.

Run Mode

When animation is active, the flow of the arrows into the load is proportional to its current MW load. You can

customize the appearance of this flow using the Animated Flows Tab of the Oneline Display Options Dialog.

Right clicking on a load (bus) field gives you the option to open the Load Field Dialog or the Load Dialog.

Edit Mode

To add a new load to the case, select Insert > Load from the main menu, or click the Load button on the Insert

Toolbar. Then, select the bus to which you want to attach the load with the left mouse button. This calls up the

Load Dialog. The bus number is automatically determined from the bus to which you attached the load. The ID field

contains a two-character ID used to distinguish multiple loads at a bus. The default ID is 1.

Enter the size, the thickness of the lines [in pixels] used to display the device, the orientation, and the base MW and

Mvar load values for the device. Usually, only the Constant Power fields are specified as nonzero. The Constant

Current and Constant Impedance fields are used to specify loads that vary with voltage. Constant current loads

vary proportionally with bus voltage, while constant impedance loads vary with the square of the voltage. Specify

the constant current and constant impedance values assuming one per-unit voltage.

Select OK to add the load. If you do not want to add the load to the case, select Cancel.

To modify the parameters for an existing load, position the cursor on the load and right-click. Select Load

Information Dialog from the local menu to invoke the Load Dialog. You can then change any parameter as desired.

You can select Format > Display/Size from the main menu to change the drawing parameters of the load.

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Load Fields on Onelines

Load field objects are used primarily to indicate various quantities associated with load devices. Furthermore, some

load field types, which are distinguished by an integrated spin button, may be used to change load device properties.

Run Mode

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

associated field.

Right clicking on a load field gives you the option to open the Load Field Dialog or the Load Information Dialog.

Edit Mode

Simulator offers two options for adding load 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 > Load Field from the main menu or the Load Field button

from the Insert Toolbar and then select the load to which you want to add the field. This invokes the Load Field

Dialog. Enter the bus number associated with the device (the default is the bus associated to the closest load 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 generator fields entails right-clicking the bus and selecting Add New Fields

Around Load from the resulting local menu. Please see Inserting and Placing Multiple Display Fields for more

details.

To modify the parameters of an existing load field, position the cursor anywhere on the object and right-click. This

brings up the Load Field Dialog. Choose Font > Line/Fill, or 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

Transmission Lines

Transmission Line Display Objects

Transmission lines are represented on the onelines using multiple segment lines drawn between buses. Transmission

lines may be equipped with circuit breakers that can be used to change the line's status. You can also add pie charts

and line fields to transmission lines to indicate how heavily loaded the line is. The appearance of transmission lines,

including line thickness and color, may also be customized.

Run Mode

Simulator's animation feature can be used to indicate the magnitude of the flow on the transmission line, either in

MW or in terms of the line's percentage loading. You can customize the line flow animation using the Animated

Flows Options on the Oneline Display Options Dialog.

Right-clicking on a transmission line displays the line's local menu, from which you can choose to inspect the

Line/Transformer Dialog.

Edit Mode

To add a new transmission line to the case, first select the Insert > Transmission Line command, or click the AC

Transmission Line button on the Insert Toolbar. Then place the cursor on the first bus for the transmission line

(the "from" bus) and click the left mouse button. Add more segments to the line by moving the cursor and clicking

with the left mouse button. To complete adding a new line, place the cursor on the second bus for the line (the "to"

bus) and double-click with the left mouse button. This calls up the Line/Transformer Dialog. The "from" and "to"

bus numbers are set automatically provided the line starts and ends on existing buses. If there is just one line

between the buses, the circuit number should be "1." For multiple lines between buses, you must give each a

unique circuit number. Enter the thickness of the lines [in pixels] used to display the transmission line. Enter the

per unit (100 MVA base) resistance, reactance, total charging susceptance (that is B not B/2) for the line, and an

MVA rating. Select OK to add the line. If you do not want to add the line to the case, select Cancel.

To modify the parameters for an existing line, position the cursor anywhere on the line and right-click. This brings

up the Line/Transformer Dialog, which you can use to change various line parameters. Choose Format >

Display/Size from the main menu to change the drawing parameters of the line.

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 clicking and holding the left mouse button down on the vertex, dragging it to a new

location, and then releasing the mouse button. 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.

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Line Fields on Onelines

Line field objects are used to show values associated with lines, transformers and dc transmission lines.

Run Mode

Right clicking on the line field gives you the option to open the Line Field Dialog or the Line Information Dialog.

Edit Mode

To enter a new line field, select Insert > Fields > Line Field from the main menu or the Line Fields button on the

Insert Toolbar and select the line, transformer, or dc line to which you want to add the field. The Line Field Dialog

will open. Enter the near and far bus number associated with the device (the default values for these fields

correspond to the device on which you clicked) and the circuit number of the device. The field will display the flow

value at the near end of the device. Enter the total number of digits to show on the screen and the number of digits

to the right of the decimal point. Finally, select the desired field type.

To modify the parameters of an existing line field, position the cursor anywhere on the object and right-click. This

again brings up the Line Field Dialog. Select Format > Display/Size from the main menu to change many of the

line field's display attributes. Choose Format > Oneline Display > Default Font to change the font for all fields on

the display.

Another way to add line fields to the oneline entails right-clicking the line and selecting Add New Fields Around Line

from the resulting local menu. Please see Inserting and Placing Multiple Display Fields for more details.

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Building a Oneline Diagram

Circuit Breakers on Onelines

Circuit breakers are used to open or close transmission lines and transformers. They are also used to place

generators, loads and switched shunts in or out of service. Closed circuit breakers are show n as solid red squares,

while open circuit breakers are shown as a green square outline. Circuit breakers cannot be placed on dc

transmission lines. To change the status of a breaker, left-click on the breaker while in run mode.

In PowerWorld Simulator, a circuit breaker directly controls the status of its associated display object. One breaker is

shown on the line connecting a generator, load, or shunt to its associated bus. Two breakers are shown by default on

transmission lines and transformers. Opening either of the line's circuit breakers opens the transmission line or

transformer, you do not have to open circuit breakers at both ends of the line.

Edit Mode

By default, when you add a new display object to a oneline diagram, the necessary circuit breakers are

automatically added at each end of the branch.

To add a new circuit breaker to the oneline, select Insert > Circuit Breaker from the main menu and then click the

line to which you want to add the breaker. The Circuit Breaker Options Dialog will appear with the from and to bus

numbers, and the circuit number automatically set to identify the line you selected. Specify the size for the switch

and its initial status, as well as whether it will be anchored to the line so that it will move with the line. Click OK to

add the circuit breaker, or click Cancel to abort the process. To add more circuit breakers to the line, simply repeat

this procedure.

To modify the parameters for an existing breaker, position the cursor anywhere on the device and right-click. This

invokes the Circuit Breaker Options Dialog, from which you can change many of the breaker's parameters.

Additional display settings for the circuit breaker can be accessed by selecting Format > Display/Size from the

main menu.

You can toggle the status of Transmission Line and Transformer circuit breakers while in Edit Mode by right-clicking

on the associated line or transformer and selecting Open Line or Close Line from the local menu.

Run Mode

Circuit Breaker status can be toggled in Run Mode by Left-Clicking on a breaker to place its associated object either

in or out of service. If the simulation is currently running, any effects of changing a circuit breaker’s status are

immediately shown on the oneline.

135

Line Flow Pie Charts on Onelines

The line flow pie charts are used to indicate the percentage MVA, MW, or Mvar loading of a transmission line or a

transformer. The degree to which the pie chart is filled shows how close the device is to its limit (provided the device

has a nonzero limit). A line flow pie chart becomes completely filled when the device's flow meets or exceeds 100% of

its rating.

Use the Pie Chart Options tab of the Oneline Display Options Dialog to customize various attributes of all pie charts.

The tab allows you to define a warning level at which the size and color of the pie charts will change to a size and

color you specify. The tab also allows you define a limit percent as well as the size and color to which to change the

pie charts when their corresponding devices violate their limits. You can also specify whether the pie charts should

reveal total power flow (MVA), real power flow (MW), or reactive power flow (MVR). The oneline display options dialog

can be invoked either by selecting Options > Oneline Display from the main menu or by right-clicking on the

background of the oneline diagram and selecting Oneline Display Options from the resulting local menu.

Right clicking on the pie chart displays the Line Flow Pie Chart Options Dialog. This dialog allows you to view the from

and to bus numbers and the circuit number of the line/transformer associated with the pie chart. You can change the

pie chart's size and the MVA rating of the line/transformer associated with the pie chart.

Edit Mode

To enter a new line flow pie chart, select Insert > Line Flow Pie Chart from the main menu or click the Line Flow

Pie Chart button on the Insert Toolbar and click on the line or transformer to which you want to add the pie chart.

This opens the Line Flow Pie Chart Options Dialog box. Enter the near and far bus number associated with the

device (these fields default to the terminal bus numbers of the device on which you clicked), the circuit number of

the device, and the desired size of the pie chart. The field will display the flow value at the near end of the device.

Enter the size of the device. Select OK to insert the line flow pie chart. Otherwise, select Cancel.

To modify the parameters of an existing line flow pie chart, position the cursor anywhere on the object and right-

click. This again brings up the Line Flow Pie Chart Options Dialog box.

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Building a Oneline Diagram

Line Flow Gauges

Line flow gauges provide a way to visualize the flow of a transmission line or transformer relative to its thermal rating.

A gauge looks very much like a thermometer. As the temperature changes, the height of the mercury in the

thermometer moves up and down. One reads the temperature measured by the thermometer by noting the marking

that matches the top of the mercury. Line flow gauges in Simulator work the same way. A line flow gauge has two

markings on its side, one for the designated minimum flow, and one for the designated maximum flow (the branch's

rating). Inside the gauge is a filled region. The default color of the filled region is blue, but this c an be changed.

When you create the line flow gauge, you associate it with a transmission element, and you specify its fill color and its

minimum and maximum flow levels. Once the gauge has been placed on a display, it will reveal changes in its

associated branch's flow by varying the height of its filled region. This tool was introduced to provide an alternative to

line flow pie charts.

To add a line flow gauge to a display, switch to Edit Mode and select Insert > Gauges > Line from the main menu.

Click on the oneline diagram where you would like the new line flow gauge to appear. The Line Flow Gauge Options

Dialog will appear. Use this dialog to define the minimum and maximum flows for the line flow gauge, as well as its fill

color and whether it should be anchored to its associated transmission element. After you click the "OK" button, the

Line Flow Gauge Options Dialog will close, and the new line flow gauge will appear.

Once a gauge has been placed on the oneline, the height of its filled region will change as the flow of its transmission

element changes. To modify any of the characteristics of the gauge, such as its key flow levels, fill color, and anchor

setting, simply right-click on the line flow gauge to open the Line Flow Gauge Options Dialog again.

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Line Flow Gauge Options Dialog

The Line Flow Gauge Options Dialog is used to define and configure a Line Flow gauge. A line flow gauge is

associated with a particular line and reveals the line’s flow relative to specified minimum and maximum thermal flow

levels. The height of the colored column in the line flow gauge indicates the line’s flow relative to these markings.

The dialog sports the following controls:

Number, Name, and Find

Use the Number and Name dropdown boxes, in addition to the Circuit field, to identify the terminal buses to which

the branch desired corresponds. It may be more convenient to press the Find button to open the Find Dialog,

which allows you to specify the line by either bus names or numbers using wildcards. When you first open the Line

Flow Gauge Dialog, the bus names and numbers will correspond to the transmission line object that was closest to

the point where you clicked.

Minimum and Maximum

Use these two spin edit boxes in the MW Rating values group box to specify the minimum and maximum flow

levels. These settings determine where on the gauge its two markings will be drawn.

The Minimum and Maximum value will be taken from the Limit Monitoring settings for the current transmission line,

unless you uncheck the option "Set Limits According to Current Limit Monitoring Settings".

Anchored

A line flow gauge is said to be anchored if, when you move its associated line object, the gauge moves with it.

Check the Anchored check box to ensure that the gauge will move with its associated line. Otherwise, when you

move its associated line object, the gauge will stay in its current position.

OK, Help, and Cancel

Click OK to finalize your settings. This will create a new line flow gauge object if you are trying to create one from

scratch, or it will modify the appearance and settings of an existing one if you have chosen to modify one that has

already been defined. Click Cancel to dispose of your changes.

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Building a Oneline Diagram

DC Transmission Line Display Objects

DC transmission lines are represented on the onelines using multiple segment lines drawn between two buses. The

line thickness and color of dc transmission lines can be customized using Format > Display Appearance from the

main menu. Line fields are often placed close to dc transmission lines on the oneline to indicate the power flow

through the device.

Note that, unlike ac transmission lines, dc transmission lines cannot be equipped with circuit breakers.

Run Mode

Simulator's animation feature can be used to indicate the magnitude of the flow on the dc transmission line, either in

MW or in terms of the line's percentage loading. You can customize the line flow animation using the Animated

Flows Options on the Oneline Display Options Dialog.

Right-clicking on a dc transmission line displays the line's local menu, from which you can choos e to inspect the DC

Transmission Line Dialog.

Edit Mode

To add a new dc transmission line to the case, first select Insert > DC Transmission Line from the main menu, or

click the DC Transmission Line from the Insert Toolbar. Then place the cursor on the bus you desire to be the

rectifier bus for the line and click the left mouse button. Add more segments to the line by moving the cursor and

clicking with the left mouse button. To complete the new line, place the cursor on the second bus for the line, which

will serve as the inverter bus, and double-click the left mouse button. This calls up the DC Transmission Line

Dialog. If you successfully selected the rectifier and inverter buses, their numbers will be automatically filled in for

you when the dialog opens.

The DC Transmission Line Record Dialog has four separate pages: Line Parameters, Rectifier Parameters, Inverter

Parameters, and Actual Flows. The separate pages can be ac cessed using the tabs shown at the top of the dialog.

These pages are used to set the modeling parameters associated with the dc lines.

To modify the parameters for an existing dc transmission line, position the cursor anywhere on the line and right-

click. This will provide access to the corresponding DC Transmission Line Dialog, from which you can modify any of

the dc line's parameters. Select Format > Display Appearance from the main menu to change the color and/or

line thickness of the dc line.

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 clicking and holding the left mouse button down, dragging the vertex to a new

location, and releasing the mouse button. 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 w here you would like

to add a vertex.

139

Multi-section Line Display Objects

Multi-section lines are represented on the onelines using a line segment with intermediate or "dummy" bus

representations. These objects are not the same as a normal transmission line. They do display animated flows in

run mode, but do not have pie charts, circuit breakers, or text fields currently associated with the objects.

Run Mode

Simulator's animation feature can be used to indicate the magnitude of the flow on the transmission line, either in

MW or in terms of the line's percentage loading. You can customize the line flow animation using the Animated

Flows Options on the Oneline Display Options Dialog.

Right-clicking on a multi-section line displays the Multi-section Line Information Dialog.

Edit Mode

Unlike transmission lines and transformers, multi-section lines CANNOT be inserted in a case by adding the mult-

section line graphically. Therefore, when inserting a multi-section line object, the data for the object must already

exist in the case. To insert the multi-section line object, first select Insert > MS Transmission Line command from

the Insert menu. Then place the cursor on the first bus for the transmission line (the "from" bus) and click the left

mouse button. Add more segments to the line by moving the cursor and clicking with the left mouse button. To

complete adding a new line, place the cursor on the second bus for the line (the "to" bus) and double-click with the

left mouse button. Completing the multi-section line opens the Multi-section Line Information dialog. At the bottom

of this dialog are display options for the line, such as line pixel thickness, symbol size (for the series capacitor

representations, if any,) anchored, and options for drawing the buses.

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 clicking and holding the left mouse button down on the vertex, dragging it to a new

location, and then releasing the mouse button. 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.

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Building a Oneline Diagram

Transformers

Transformer Display Objects

Transformers are represented as transmission lines with two opposing coils drawn on one of the segments. The

transformer's line thickness, color, and symbol segment can be customized using the Edit Mode. Optionally, circuit

breakers and pie charts can be placed on the transformer. Clicking on the circuit breakers changes the status of the

transformer.

Line fields are often placed close to transformers on the oneline to indicate the power flow through the device.

Transformer fields are often placed close to transformers on the oneline to indicate and control their tap positions.

See Transformer Modeling for details on modeling either LTC or phase shifting transformers.

Run Mode

Simulator's animation feature can be used to indicate the magnitude of the flow through the transmission line, either

in MW or in terms of the transformer's percentage loading. You can customize the line flow animation using the

Animated Flows Options on the Oneline Display Options Dialog.

Right-clicking on a transformer displays the line's local menu, from which you can choose to inspect the

Line/Transformer Dialog.

Edit Mode

New transformers are inserted in much the same way as transmission lines. To add a new transformer to the case,

first select Insert > Transformer from the main menu, or click the Transformer button on the Insert Toolbar. Then

place the cursor on the first bus for the transformer (the from bus) and click the left mouse button. Add more

segments to the transformer by moving the cursor and clicking with the left mouse button. To complete the new

transformer, place the cursor on the transformer's other terminal (the to bus) and double-click with the left mouse

button. This calls up the Line/Transformer Dialog. The from and to bus numbers for the transformer should have

been set automatically. If there is just one transformer between the buses, the circuit number should be "1." For

multiple transformers between buses, you must give each a unique circuit number. Enter the thickness of the lines

[in pixels] used to display the transformer, the number of the line segment in which you would like the transformer

symbol drawn, and the size of the transformer symbol.

Enter the per unit (100 MVA base) resistance, reactance and charging susceptance for the transformer, and an

MVA rating. Enter the off-nominal tap ratio and the phase shift angle in degrees. (For a transformer without tap or

phase control, the off-nominal tap should be 1.0 and the phase shift angle should be 0 degrees.)

Select the appropriate Automatic Control Option. If the transformer does not have tap control, select No Automatic

Control (this is the default). Select AVR (Automatic Voltage Regulation) if the transformer changes its tap ratio to

control the voltage at user specified regulation bus. Select Reactive Power Control if the transformer changes its

tap ratio to control the reactive power through the transformer. Finally, select Phase Shift Control if the transformer

changes its phase shift to control the MW flow through the transformer. If you need any of the last three options,

select the Automatic Control Options button to set the parameters associated with the automatic control.

For AVR control, enter the number of the bus whose voltage is to be controlled, the allowable range for the

controlled voltage (in per unit), the minimum and maximum tap ratios (typical values are 0.9 and 1.1), and the step

size for the discrete changes in the tap ratio (typical value is 0.00625).

For reactive power control, the control variable is always the reactive power measured at the from bus (i.e., the

tapped side) of the transformer. Positive flow is assumed to be going through the transformer to the to bus . Enter

the minimum and maximum allowable flows, the minimum and maximum tap ratios (typical values are 0.9 and 1.1),

and the step size for the discrete changes in the tap ratio (typical value is 0.00625).

For phase shift control, the MW flow through the transformer is the controlled value. Enter the bus number of the

terminal whose flow is controlled, the allowable range for the controlled flow (positive flow is assumed to be into the

transformer at the terminal entered in the previous field), the minimum and maximum phase angles (typical values

are -30° and 30°), and the step size in degrees (typical v alues are between 1° and 2°).

Select OK to save the values and return to the Transformer Options Dialog; otherwise select Cancel.

If you would like the transformer to be initially modeled as being on automatic control at the start of the case, select

the Automatic Control Active checkbox.

If you do not want to add the transformer to the case, select Cancel.

To modify the parameters for an existing transformer, position the cursor anywhere on the device and right-click.

This brings up the local menu from which you can choose to view the Line/Transformer Dialog. Use the

Line/Transformer Dialog to adjust many of the transformer's electrical properties. Select Format > Display

Appearance to change the transformer's color and/or line thickness.

See Transformer Modeling for details on modeling either LTC or phase shifting transformers.

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Transformer Fields on Onelines

Transformer fields are used to show field values specific to transformers, such as tap position, phase angle, and more.

Run Mode

If there is a spin control integrated with the field, you can click on the spinner to change the field's value by the

associated Delta Per Mouse Click.

Right clicking on the transformer field gives the option to display the Transformer Field Dialog or the

Line/Transformer Information Dialog.

Edit Mode

To enter a new transformer field, select Insert > Fields > Transformer Field from the main menu or the

Transformer Field button on the Insert Toolbar, and then click on the transformer object to which you want to add

the new field. This calls up the Transformer Field Dialog. Enter the from and to bus numbers associated with the

device (the default values for these fields correspond to the transformer 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 off-nominal tap ratio, the off-nominal

tap position, or the phase shift angle in degrees.

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

to bring up the Transformer Field Dialog. Use the Format > Display Appearance main menu option to change

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

Format > Oneline Display > Default Font option to change the font for all fields on the display.

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Building a Oneline Diagram

Series Capacitors

Series Capacitor Display Objects

Series capacitors are represented as transmission lines with two opposing parallel bars drawn on one of the

segments. The series capacitor’s line thickness, color and symbol segment can be customized using the Edit Mode.

If the series capacitor branch is operating, but the series capacitor status is set to Bypassed, a low impedance

segment will be drawn around the series capacitor symbol to indicate the capacitor has been bypassed. The capacitor

status of Bypassed or In Service can be toggled in run mode if the Series Capacitor Status field is displayed on the

oneline diagram. When a left-click is registered on the Series Capacitor Status field when in Run Mode, the capacitor

status is toggled. Note that this is not the same as the overall branch status of Open or Closed.

Optionally, circuit breakers and pie charts can be placed on the series capacitor. Clicking the circuit breakers changes

the branch status of the series capacitor.

Run Mode

Simulator's animation feature can be us ed to indicate the magnitude of the flow through the series capacitor, either

in MW or in terms of the transformer's percentage loading. You can customize the line flow animation using the

Animated Flows Options on the Oneline Display Options Dialog.

Right-clicking on a transformer displays the line's local menu, from which you can choose to inspect the

Line/Transformer Dialog.

Edit Mode

New series capacitors are inserted in much the same way as transmission lines. To add a new series capacitor to

the case, first select Insert > Series Capacitor from the main menu, or click the Series Capacitor button on the

Insert Toolbar. Then place the cursor on the first bus for the series capacitor (the from bus) and click the left mouse

button. Add more segments to the series capacitor by moving the cursor and clicking with the left mouse button.

To complete the new series capacitor, place the cursor on the series capacitor's other terminal (the to bus) and

double-click with the left mouse button. This calls up the Line/Transformer Dialog. The from and to bus numbers

for the series capacitor should have been set automatically. If there is just one branch between the buses, the

circuit number should be "1." For multiple branches between buses, you must give each a unique circuit number.

Enter the thickness of the lines [in pixels] used to display the series capacitor, the number of the line segment in

which you would like the series capacitor symbol drawn, and the size of the series capacitor symbol.

Enter the per unit (100 MVA base) resistance, reactance and charging susceptance for the series capacitor, and an

MVA rating. On the Series Capacitor tab, check the box labeled Is Series Capacitor to indicate that the branch

model is a series capacitor device.

If you do not want to add the series capacitor to the case, select Cancel. Otherwise click OK to add the series

capacitor to the case.

To modify the parameters for an existing series capacitor, position the cursor anywhere on the device and right-

click. This brings up the local menu from which you can choose to view the Line/Transformer Dialog. Use the

Line/Transformer Dialog to adjust many of the series capacitor's electrical properties. Select Format >

Display/Size to change the series capacitor's color and/or line thickness.

See Series Capacitor Information for more details on modeling series capacitors.

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PowerWorld Simulator version 11. Manual - page 4