Other Contingency Actions

See Also

 

Clicking the Other > button on the bottom of the Contingency Analysis dialog provides access to various actions as described below:

Delete All Contingencies

Click this to delete all the contingencies presently stored in memory.

Clear All Contingency Results

Click this to clear all the results of the contingencies from memory. This will not delete the contingencies.

Set As Reference

Click this to set the case presently in memory as the Reference State for contingency analysis. For more information on the reference state, see Contingency Case References.

Restore Reference

Click this to set the state of the present power system case back to the contingency analysis reference state. For more information on the reference state, see Contingency Case References.

Convert Contingencies to Transient Contingencies

This option will create transient contingencies from the currently defined steady state contingencies based on a hardcoded set of assumptions. Additional changes may be required to completely model the transient events, but this functionality provides a starting point for a conversion.

The following assumptions are used in the conversion:

• Fault on time
• 1 second
• Fault location
• If first element in contingency is a bus, apply fault at that bus
• If first element in contingency is a branch, apply fault at from bus of that branch
• If first element in contingency is anything except a bus or branch, do not apply a fault but do open all elements at 1 second
• Fault type
• Balanced 3 phase
• Fault clearing time
• Bus fault
• 500 kV bus use 1 second plus 3 cycles
• 230 kV bus use 1 second plus 4 cycles
• 115 kV bus use 1 second plus 6 cycles
• Branch fault
• 500 kV branch use 1 second plus 3 cycles at from end and 1 second plus 4 cycles at to end
• 230 kV branch use 1 second plus 4 cycles at from end and 1 second plus 5 cycles at to end
• 115 kV branch use 1 second plus 6 cycles at from end and 1 second plus 7 cycles at to end
• Time at which to change remaining elements
• If bus fault open all remaining elements when fault is cleared
• If branch fault open all remaining elements when to end of the line is opened

Convert to Device Contingencies

This command is intended for use with full topology models, where breakers and disconnects are defined in addition to generators, loads, transmission lines, etc. This function would have no affect on a traditional planning model representation in which no breakers or disconnects are explicitly defined.

The purpose of this option is to allow the user to take a contingency set that is defined with outages of breakers and disconnects in a full topology model and convert them to outages of the traditional planning model elements, such as generators, loads, transmission lines, etc. This would be used in conjunction with the ability to save a full topology model as a consolidated model. A consolidated model reduces the full model down to a traditional planning model by examining the breaker and disconnect statuses and reducing the system down by consolidating breakers and disconnects that are in service. The resulting model is a smaller model with the traditional planning elements represented, but breakers and disconnects have been removed and nodes aggregated into bus representations. This function will also take the breaker and disconnect statuses and convert them into contingencies of the planning model devices affected by opening the original breakers or disconnects. Thus, you could create a contingency that is defined for the consolidated model and can be run on the consolidated model with the same results as if the original contingency set is run on the full topology model.

The contingency set generated depends on the statuses of the breakers and disconnects, and the contingencies created will be different for the different statuses of breakers and disconnects in the full topology model.

There are two options when converting to device contingencies:

Keep Only Devices

This is the default functionality where the contingency results will only contain the devices that are affected by the operation of breakers in the original contingency definition. This could result in contingencies with no actions if no devices are found that are affected by the breakers in the contingency.

Keep Original If Empty

After the conversion process is complete, original breaker definitions will be retained for any contingencies that end up with no actions. This could result because no devices are found that are affected by the original breakers in the contingency. This functionality is necessary if there are contingency definitions that open single breakers without the intent of isolating other devices.

Cleanup Blocks and Global Actions

Merge Contingency Block Elements

Selecting this will eliminate contingency blocks by adding the elements that are in contingency blocks to the contingency elements, Global Actions, or Remedial Actions that are using the blocks. We strongly encourage you to discontinue use of Contingency Blocks.

Convert Global Actions Into Remedial Action

Selecting this will convert legacy Global Actions into a more versatile Remedial Action. A single Remedial Action will be created. We strongly encourage you to use Remedial Actions instead of Global Actions.

Combined Tables

Contingency Violation Matrices

Clicking Process Contingency Results will go through the existing contingency analysis tool results and build tables showing the limit violation values for all violated branches, interfaces, buses, bus pairs, custom monitors and the contingencies for which each element is violated. Upon opening, it is possible to limit processing to branches, buses, interfaces, bus pairs, and/or custom monitors. Also, you can specify whether to display percentages or actual flows in the resulting tables.

Contingency Violation List

Opens a table of all violations for all contingencies.

Contingency Element Definitions

Opens a table of all individual contingency actions from the current contingency list.

What Actually Occurred?

Opens a table of all individual records indicating which actions were applied or skipped for the current contingency list.

Produce Report

Select this option to produce a detailed report of the results of the contingency analysis. This will launch a save window that will save the information you customized on the Report Writing page. You will also be given the option of viewing the report in WordPad immediately after creating the file.

Compare Two Lists of Contingency Results

Click this to open a dialog which allows you to specify two sets of contingency analysis results to compare. For more information on this comparison, see Comparing Contingency Analysis Results.

Filter Results Using Limit Monitoring Settings

Click this to filter the contingency analysis results using the present Limit Monitoring Settings. This action will go through each violation for each contingency and verify that the element that was violated is set to be monitored. If the element is not set to be monitored, then Simulator will flag the violation internally as inactive. You will then not be able to see these violations on any of the displays, although they will still be saved in memory until you delete these contingencies, or reprocess them. These violations will also not be saved when you choose to save the contingency results.

Because the violations are saved in memory however, you can get them back without reprocessing the contingency list. To do this, change your Limit Monitoring Settings so that those violations will be set for monitoring again. Then click this option again.

When using this option, keep in mind that Simulator cannot filter results that do not exist in memory. If the filter is to be used to filter out different percentages of overload, then the contingency analysis should be run with the lowest percentage desired. For example, if the filter option is to be used to give all of those elements that are loaded above 70% of their limit and then those that are loaded above 90% of their limit, the contingency analysis should be run with the Limit Monitoring Settings defined to monitor elements that are loaded at 70% of their limit. Also, keep in mind that the more elements are monitored the slower the processing will be.

Auto-fill Blank Contingency Element Comments

Selecting this option will fill the Comment field of the Contingency actions in the Contingency Definition table with a copy of the contingency action definition. The action description itself cannot be modified, but the comment can be modified to be more descriptive of the action being taken, for your own reference.

Sensitivity Calculations >

Simulator provides the PTDF tool for calculating the impact of a MW transfer on all the transmission lines in the system. The Simulator ATC tool further extends the linearized methods by integrating linearized contingency analysis with the PTDF calculations. The sensitivity calculations provided here are an extension of this. They allow you to ask the question, How will each contingency-caused branch or interface violation be affected by a MW transfer?. This calculation is not relevant for bus violations.

Calculate OTDFs using existing PTDFs

Before executing this, you must first go to the PTDF Dialog and calculate the PTDFs for the transfer direction you are interested in. These PTDF values will then be used throughout the OTDF calculation. Click this to calculate OTDFs for each contingency-caused branch or interface violation. The values calculated will be a measure of what percent of a transfer would appear on the branch or interface after the respective contingency occurs. Realize for branch violations, that the sign of the OTDF value will be relative to the direction of the MW flow found during the contingency analysis (see the Element description on the Contingency Violations Display).

The OTDF and PTDF values for each violation for which they have been calculated can be found in either the Contingency Violations Display that is used to list the violations for a contingency selected in the Contingency Records Display or the Contingency Violation List, which lists all violations for any contingency and is found on the Results tab of the contingency analysis dialog. The OTDF and PTDF fields are not shown by default in these tables and will need to be added.

The following options are applicable when calculating the PTDFs and LODFs needed for calculating the OTDFs:

• Transfer direction is specified with the PTDF calculation options for Seller and Buyer
• The calculation method selected with the PTDF calculation options determines if phase shifters are assumed to enforce their flow during the PTDF and LODF calculations. Phase shifters will only be enforced if selecting the Lossless DC with Phase Shifters option.
• Make up power is determined by the contingency analysis setting for make up power. If the Area Participation factors specified below option is selected, that will be used, otherwise the Generator Participation Factors From Entire Case Directly option will be used.
• When calculating LODFs the DC power flow model options for DC Power Flow Line Model, Ignore Transformer Impedance Correction Tables, and Ignore Phase Shift Angle Effects are used.
• To include the effects of conditional actions when determining the linear impact of the contingency, the contingency option to Iterate on Action Status can be used

Filter out Violations Using OTDFs

Once you have calculated the OTDFs using the existing PTDFs, you can then filter the results by selecting this option. A dialog will appear for you to enter a minimum OTDF value. All violations that have an OTDF smaller than this number will be flagged as inactive and will not show up in the list of violations. See the note above regarding the Filter Results using Limit Monitoring Settings to better understand how inactive violations are treated.