A Ccc Report

8/13/2019 A Ccc Report

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LAB4 AC CONTINGENCY CALCULATION REPORT

EE461: POWER SYSTEMS

COLORADO STATE UNIVERSITY


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Lab 4 Create AC Contingency Calculation Report

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Trace starts the program. The next line names the (N-1) contingency. The third line

describes which line will be removed. The next line ends the contingency. Then theprocess is repeated for all (N-1) contingencies that are desired.

Monitor file (*.mon)

The monitor file tells the power flow simulator which branches to be supervised during

the (N-1) contingencies. A sample of the monitor file will now be given:

COM

COM Monitored Element Description File for SAMPLE Study, Outage

COM

MONITOR BRANCHES IN SUBSYSTEM OVERAL

MONITOR VOLTAGE RANGE SUBSYSTEM OVERAL 0.90 1.10

MONITOR VOLTAGE DEVIATION SUBSYSTEM OVERAL 0.5 0.5

MONITOR INTERFACE ZONE6H RATING 500 MW

152 3004

3002 3004

ENDEND

The first line after the comments informs which branches to monitor in the subsystem

named OVERAL. The second line sets a per unit voltage range for that subsystem. Thethird line gives a +/- deviation from the prescribed values in line two. The fourth line

indicates the power rating for a defined set of lines. The following two lines tell exactly

which branches to monitor (from bus # to bus #). The first END ends that particular zone

to be monitored. This is repeated for each additional zone that may be of interest, and thisfile is completed with a final END to stop the monitor file.

Subsystem file (*.sub)

The subsystem file informs the power flow analysis to only look at a prescribed section,

or zone, of the overall network. A sample of the subsystem file will now be given:

COM

COM System discription file for SAMPLE FLOW STUDY

COM

SUBSYSTEM OVERAL

BUS 101

BUS 102

BUS 151

BUS 152

BUS 153BUS 154

BUS 155

END

END

The first line after the comments names the subsystem OVERAL as indicated in themonitor file. The seven bus number lines indicate which busses are to be included in the

subsystem. The first end stops the subsystem and the final end concludes the file.


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ACCC

The contingency, monitor, and subsystem files are utilized by the AC Contingency

Calculation (ACCC) feature of PSS/E to perform a power flow study on a prescribed

zone. The ACCC produces an analysis of the power system.

Using the *.con, *.mon, and *.sub to create an ACCC report

For the purpose of this lab a sample.con, sample.mon and sample.sub file are provided as

examples to perform an ACCC analysis. Start PSS/E and load the sample.sav file. To

perform an ACCC analysis click on the Power Flow drop down menu and selectSolutionAC contingency solution (ACCC).

The AC Contingency Solution window will be displayed:


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A Distribution Factor Data File (DFAX) needs to be created by loading the provided

sample.con, sample.mon and sample.sub files. Click on the Create DFAX button, andthe Build Distribution Factor Data File window will be displayed:

Click on the three dots next to the Subsystem description data text field to load

the sample.sub file.

Locate the directory containing the sample files to select the Sample.sub file and clickOpen. The sample.sub file will be loaded in the Subsystem description data text field in

the Build Distribution Factor Data File window.


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Next, click on the three dots next to the Monitored element data text field to loadthe sample.mon file.

Select the Sample.mon file and click Open. The sample.mon file will be loaded in the

Subsystem description data text field in the Build Distribution Factor Data File window.

Now, click on the three dots next to the Contingency description data text field to

load the sample.con file.

Select the Sample.con file and click Open. The sample.con file will be loaded in theSubsystem description data text field.


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Next, a location for the DFAX output file needs to be assigned. This is done by clicking

on the three dots next to the Distribution factor data output file text field.

Select the File name text field, type sample.dfx to name the DFAX output file, and

click Open. This will create the output file in the directory listed in the window and can

be created in a different directory if needed. The sample.dfx file will be loaded in theDistribution factor data output file text field in the Build Distribution Factor Data File

window.

The Build Distribution Factor Data File window will look like the one below after all thesample files and Distribution factor data output file have been specified.

Click OK to return to the AC Contingency Solutions window, with the sample.dfx file

loaded in the Distribution factor data output file text field.


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Finally, a location for the ACCC output file needs to be assigned. This is done by

clicking on the three dots next to the Contingency output file text field.

Select the File name text field, type sample.acc to name the ACCC output file, and click

Open. This will create the output file in the directory listed in the window and can be

created in a different directory if needed. The sample.acc file will be loaded in theContingency output file text field in the AC Contingency Solution window as shown

below:

Click Solve to solve the system with the loaded sample files.

Now, click Reports to load the AC Contingency Reports window:


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Leave everything set to the default values and click the Go button to run the ACCC

report.

Click close to exit the AC Contingency Reports window, click close again to exit the ACContingency Solutions and return to the terminal window.

Click on the report tab to view the completed ACCC Report.


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The monitored branch section shows all the branches that were overload due to a

contingency. The contingency section shows which branch was automatically taken outof service by the ACCC, which resulted in an overload. The base case contingencies

show the system intact overloads before any branches were removed from service.

Scroll to the right on the report window to view the rating of the line in MWs, the powerflow of the line in MWs, and the percent overload.

At the bottom of the report the Monitored voltage report & Contingency legend can be

seen, but is not of significant importance for this lab.


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QuestionsThe sample.sav data file must be open to perform this section of the lab.

Using the sample.con contingency file, the sample.mon monitor file and the

sample.sub subsystem file that have been provided, create a sample.dfx DFAX and a

sample.acc AC contingency file. Solve the system with the loaded sample files and runthe ACCC report as shown above. View the report generated by PSS/E and print out the

report, this print out will need to be included in the lab report. It will also be helpful inanswering the following questions.

1) Which six branches suffer from overloads during the BASE CASE contingencyand what is their percentage of overload? ______________ ________

_ ______________ _____ _

2) Looking at the NUC-HYDRO contingency, which branches suffer fromoverloads that did not suffer from overloads during the Base Case, and what is

their percentage of overload?_________ _____ __ ____Of the branches suffering from overloads during the Base Case, which one(s)

got worse during this contingency, and by how much?________ __

____ __ ____Did any of these branches actually see a reduction in overload, if so, which ones

and by how much were they reduced?________ __

____ __ ____

3) Which of the contingencies created the highest number of overloaded branches?

___ ____ __ __

Which branch was taken out of commission in this contingency? __ _ ____

__ __ __ __

4) Find the DNTN-CAD contingency. What is the rating of the branch betweenbus #202 and #203 (in MW) and what is the actual power flow (in MW) on this

branch? __ __ __

What is the rating of the branch between bus #204 and #205 (in MW) and what is

the actual power flow (in MW) on this branch? _ _

__ _ _Assuming a power factor of 0.9, how much actual power (in MVA) must the

power company provide to each of these branches? _ _

__ _How much actual power (in MVA) must the power company provide to each of

these branches if the power factor was at 0.8, just 10% lower? _ _

_ _

Documents

A Ccc Report