Interface Display

See Also

 

The Interface Display is used to show the net real power (MW) flow on a group consisting of one or more of the following devices: 1) transmission lines (AC and DC) and/or transformers, 2) total tie-lines between two adjacent areas, 3) total tie-lines between two adjacent zones, 4) Generators and Loads, 5) Injection Groups, 6) multi-section lines, 7) other interfaces and 8) Contingency Actions . Interface information is useful because secure power system operation often requires that the flow on such groups be less than some limit value. For example, interface information could be used as "proxies" for other types of security constraints, such as voltage or transient stability limitations. Another major potential use for interfaces is in the Optimal Power Flow solution to monitor flows on groups of devices, such as a set of transmission lines, generation leaving a plant, load demanded in a certain region, etc. Interface information can also be extremely useful for summarizing the flows occurring on a large network. Interface flows can be monitored using the Limit Monitoring Settings Display.

The Interface Display presents more detailed information for each interface that has been defined for the case. The Interface Display is a class of Case Information Display and therefore can be used in a manner consistent with all other case information displays. It has a local menu from which you can print, copy, and modify its information as well as view the information dialog of its associated interfaces. The local menu also affords the opportunity to insert new interface definitions either singly (Insert) or as a group (Automatic Insertion) into the model or to delete existing ones. In addition, PowerWorld has also added options for reading NERC flowgate files (Load NERC Flowgates) and writing NERC flowgate files (Save NERC Flowgates) to the local menu.

You can sort the interface information by clicking on the heading of the field by which you want to sort. Additionally, you can choose to restrict the information shown by the Interface Display according to the constraints of the area/zone/owner filters.

To show the interface display, select Aggregations > Interfaces in the Model Explorer.

Interface information can be saved in the "*.aux" auxiliary file format. See Auxiliary Files for details.

The interface Display is divided into two tabs: Interface and Interface Elements.

 

Interface Elements Tab

The Interfaces Elements tab has a list of tabs which lists each types of element that can belong to an interface. There is a check-box below in the middle of the display which allows you to Only show elements that belong to at least one interface. As you select an element in the top half of the display, the bottom half of the display will list each interface which contains the selected element. Again, these provide a nice way to look through the elements that make up each interface.

Interface Tab

The Interfaces tab has a list of interfaces at the top of the display. When on the Interface tab, in the bottom half of the tab is a set of subtabs which display all the elements of the presently selected interface from the top half of the display. This set of sub tabs starts with the Elements tab which lists all the elements of the interface regardless of the type of element. The remainder of the tabs each lists the interface elements of a specific type of interface element such as Branches, Branch Open/Close, DC Lines, Generators, Loads, Injection Groups, Multi-Section Lines and other interfaces. These subtabs provide a nice way to look through the elements that make up each interface. The top half of the Interface display contains the following fields:

Number

Numeric identifier for the interface.

Name

Alphanumeric identifier for the interface (24 characters maximum).

Interface MW

Current MW flow on the interface. This flow is the sum total of the Base MW Flow and the Contingent MW Flow.

MW Limit

Current rating for the interface in MW.

Percent

The actual MW flow on the interface as a percentage of the MW limit.

Monitor Direction

The current direction in which the MW flow is being monitored. The possibilities are From - To or To - From.

Monitor Both

Toggle this field to Yes in order to monitor the flow on the interface in both directions, instead of a single direction as designated by the Monitor Direction field.

Lim MW A, Lim MW B, Lim MW C

These three fields display the values of the three possible limits for the interface.

Has Contingency

This is a Yes or No field that will be set to Yes if any of the elements making up part of the interface are at a device limit.

Contingent MW Flow

If the interface defined contains a contingency action, the Contingent MW Flow is the approximated flow amount that would be added to the interface should the contingency occur.

Base MW Flow

The base MW flow is the flow on the interface prior to any considered contingency elements.