DataTransfer.pdf

Transferring Network Data To and From the CAPE Database

in the Computer-Aided Protection Engineering System

(CAPE)

Prepared for

CAPE Users’ Group

November 2007

Electrocon International, Inc. Ann Arbor, Michigan

This document is the sole property of Electrocon International, Inc. and is provided to the CAPE Users Group for its own use only. It may not be supplied to any third party, or copied or reproduced in any form, without the express written permission of Electrocon International, Inc. All copies and reproductions shall be the property of Electrocon International, Inc. and must bear this ownership statement in its entirety.

Transferring Data

Introduction There are eight separate data conversion utilities for converting external data to an empty CAPE database. The supported input data formats are: • ANAFAS • Aspen OneLiner • DIgSILENT • Electrocon International, Inc. PSA Short Circuit • Energy Australia FAULTY • General Electric PSLF • Power Technologies, Inc. PSS/E • Power Technologies, Inc. PSS/U To use any of these utilities, click Start | Programs | CAPE | Data Conversion followed by your choice of the third-party program format. You will be asked to specify an existing database file that can serve as the template for the new one. Typically, this will be either |CapeUserDir|\cape_starter.gdb or empty_starter.gdb in your working directory. The former has the master CAPE protection device library but no network data; the latter is truly empty except for having the necessary internal structure. The input data file conversion utilities are separate programs that reside in |CapeHomeDir|\progs. This document will assume that CAPE is installed in \cape and that both the user and working directories are \cape\dat. In addition, CAPE can generate data files for four of the above formats, with or without a network reduction first, for all network data read from the database. The supported output formats are: • ANAFAS • Aspen OneLiner • Power Technologies, Inc. PSS/E • Electrocon International, Inc. PSA Short Circuit

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Transferring Data

Transferring ANAFAS Data to a CAPE Database The CAPE program to transfer an ANAFAS format network data file to an empty CAPE database is located in |CapeHomeDir|\progs, and is named iANAFAStoDB.exe. To transfer data to a new CAPE database, perform the following steps. 1. Prepare a directory where you wish the converted data to reside. The examples

use C:\My_Data.

2. Click Start | Programs | CAPE | Data Conversion | ANAFASToDB. This window will appear:

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3. Network data file: Specify the location and name of your ANAFAS .ANA or .DAT data file; it is easiest to use the “?” button for this.

4. Template gdb: Select the CAPE database file to be used as a template for your new database. Typically this will be either \cape\dat\cape_starter.gdb or \cape\dat\empty_starter.gdb.

5. Target gdb: Use the “?” button to search to the directory where the new database is to be created, enter the desired name in the Windows form, and click “Open.” If a file of this name already exists, it will be overwritten by a copy of the Template. If the file does not exist, one will be created by copying the Template.

6. Minimum branch impedance: ANAFAS does not support the concept of a bus tie,

i.e. a zero-impedance switch. Instead, such switches are often represented in ANAFAS by branches of low impedance. Specify here the threshold at or below which the CAPE conversion program should replace a branch by a bus tie. Enter 0.0 if no such conversion is to be done.

7. Create Substations. ANAFAS does not support the substation data construct.

Check this box if you want CAPE to create substation names (based on bus names) for you.

8. Extra output to log file: The CAPE conversion programs all write status, warning,

and error messages as appropriate during the conversion process. You can limit these messages to only the most important ones if you leave this box unchecked.

9. Specify whether your ANAFAS file uses 4-digit or 5-digit bus numbers. 10. Click Begin Conversion to start the data transfer. Now ANAFAStoDB reads the network data and adds it to the database. A permanent log file, log_file.txt, is created in the working directory and will contain all information written to the screen. When ANAFAStoDB is finished, your new database is ready to use with CAPE. You should review the log file to make sure no errors occurred. If any problems arise during the conversion, re-run the conversion with the box “Extra output to log file” checked. You may get an indication of what is wrong and at least you will know the last line read from the data file before the error occurred. Implementation Notes 1. Bus Numbers The 4-digit or 5-digit ANAFAS bus numbers are read as the CAPE bus numbers, depending on your ANAFAS version: 4.2 and earlier, or 4.3 and more recent. iANAFAStoDB accepts all the changes in the version 4.3 ANAFAS format [1].

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2. Shunts, Lines, and Transformers iANAFAStoDB classifies the branches into shunts, lines, and transformers.

• If either bus is a midpoint (MP=1), the branch is a transformer.

• If either bus is 0, it is a shunt.

• If it is a shunt and z1 is finite, and TIPC is not "C", "H", or "R", it is a generator or machine.

• Shunts with TIPC codes "C", "H", "R" are loads or passive shunts. They are

ignored in iANAFAStoDB (for a "classical" Short-Circuit solution).

• A shunt with z1 infinite is either a grounding transformer or part of a wye-delta transformer that is identified later.

Otherwise this is a series branch.

• If x1 < 0 and x0 < 0 and r1 = 0 and r0 = 0, it is a series capacitor.

• If Z0 is infinite or is labeled as TIPC="T", it is a transformer. For two-winding grounded-Y-grounded-Y transformers Z0 is finite, so you must specify TIPC as "T".

• If TIPC='R', it is a series reactor (BRANCH_TYPE "REAC").

• If TIPC='C', it is a series capacitor (BRANCH_TYPE "CAPA").

• Other branches connecting different base kV levels are stored with a type of

"EQIV".

• The remaining branches are LINE branches. For a reactor, capacitor, transformer, or bus tie, all the end buses are placed in the same substation. CAPE copies the substation ID from the name of the first end bus found in the ANAFAS bus data, excluding internal transformer buses. You may leave the branch circuit numbers blank in the ANAFAS data. Program iANAFAStoDB replaces the blank by the lowest available circuit number: 1 if this is the only branch between the two buses. The same branch with a blank circuit number is recognized in the Mutual Coupling data. If two branches between the same buses both have blank circuit numbers, an error message is printed.

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3. Line Names The program iANAFAStoDB adds a prefix "L_" to line names that begin with a number. Non-alphanumeric characters are replaced by underscores. 4. Transformer Taps The CAPE-to-ANAFAS export function outputs a transformer tap defined as

XFMR fixed tap kV at FROM-BUS Bus Base kV at TO-BUS*Bus Base kV at FROM-BUS XFMR fixed tap kV at TO-BUS

This is 1.0 unless you have set "Use Fixed Taps ON" in the CAPE Executive Setup Menu. This definition shows that iANAFAStoDB cannot uniquely invert the process and find both fixed tap voltages from the single transformer tap. We avoid this problem by treating all ANAFAS taps as 1.0. This is adequate for a "classical" short-circuit solution. 5. Transformer Windings and Impedances Program iANAFAStoDB stores transformer branches as PI-model transformers with a type of "XFMR". iANAFAStoDB uses the equivalent branch model directly instead of producing a more detailed N-Circuit transformer model, because the ANAFAS file does not contain enough information about the winding types and test impedances. Three-winding transformers are modeled with a "T" branch model. These transformers have three branches at a common "mid-point" bus. iANAFAStoDB recognizes the branches because one end bus is of midpoint type (MP=1). Branches that connect two such "mid-point" buses are assumed to be parts of a more complex transformer model (e.g. four-winding). If a tertiary delta winding is "buried" and has no external terminals, the three-winding transformer model can have only one or two branches. This model is used as given, and zero-sequence shunts at the transformer bus are moved to the branch. The following rules apply to two-winding transformer series branches that are open connections for neutral currents and have infinite zero-sequence impedance. They may be Wye-Delta, Delta-Wye, or Delta-Delta transformers. A grounded-Wye-Delta transformer has a zero-sequence equivalent shunt at the bus. Parameters TB and TC match the shunt to a particular transformer branch. They are not always available in production data.

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a. TB and TC given Program iANAFAStoDB reads the TB and TC values from the ANAFAS file. TB and TC are used only for zero-sequence-only shunts. Let the shunt be at bus A: TC >< Wye >< Delta A-----------><-----TB | >< | >< | ----- --- - If TB is a positive number, the branch from bus A to TB with circuit TC is a wye-delta transformer with the delta winding at TB. The shunt at bus A becomes part of the transformer zero-sequence model. If the transformer branch has a blank circuit number, TC must also be blank. If no matching branch is found, the shunt is left on bus A and the values of TB and TC are ignored. b. TB and TC not given. If TB is zero, blank, or invalid, the iANAFAStoDB program has to make a reasonable guess for the winding types. In this case, iANAFAStoDB will read the angle DEF for each transformer at the bus. DEF applies to the positive-sequence voltages and equals the phase lead of the to-bus winding from the from-bus winding with load ignored. If DEF is zero, the windings are DELTA-DELTA, since the zero sequence connection is open and there is no phase shift. If DEF is a multiple of +/-30 degrees, the bus with the zero-sequence shunt is a WYE winding and the other bus has a DELTA winding. If both buses have zero-sequence shunts, the from-bus is WYE and the to-bus is DELTA. If DEF is blank (missing), the windings are set as DELTA-DELTA and a warning states that DEF, TB, and TC values are needed for this transformer. Example with two parallel delta-wye transformers: The delta winding is at bus 10. The leakage impedances are 0.0111 and 0.0222 perunit for transformers 1 and 2.

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(BF C BT NCT R1 X1 R0 X0 CN TB TCIA DEF KM (----= ===== -=-------======------======------ -----==---=== ( --- Xfmr 1, between buses 10 and 1 with no mid-point; TB indicates Delta 0010 0001 1T 111999999999999TRF.1 110 30 0 0001 1T999999999999 111TRF.1 0010 1110 ( --- Xfmr 2, between buses 10 and 1 with no mid-point; TB indicates Delta 0010 0001 2T 222999999999999TRF.1 110 30 0 0001 2T999999999999 222TRF.1 0010 2110 ( ----------------------------------------------------------------------------

6. Implicit Delta-Wye Phase Shifts. Delta-wye transformers shift positive-sequence currents and voltages by a phase angle of +/- 30 degrees, and shift negative-sequence currents and voltages by the opposite angle. The angle affects computed branch currents where a delta-wye transformer lies between the branch and the faulted bus. The ANAFAS data field "DEF" is the phase lead of the to-bus positive-sequence voltage from the from-bus. The effect on the three-phase currents and voltages is to convert phase-ground quantities on the wye side to phase-phase quantities on the delta side. The database schema allows CAPE to store the angle for a transformer branch. Wherever DEF is given, iANAFAStoDB now stores the transformer reference angles in the database. Then you can use the angles as given or recompute them when CAPE builds the Short-Circuit network. To set the bus angles in CAPE, set one of the following options in your configuration file (|CapeUserDir|\cape.cfg) or on the CAPE command line. Then rebuild the Short-Circuit network.

BUS_REFERENCE_ANGLES 0 Set all reference angles as zero. BUS_REFERENCE_ANGLES 1 Use all bus reference angles already in

the database. BUS_REFERENCE_ANGLES 2 Use the branch angles and the N-Circuit

transformer IMPLICIT_ANGLE and derive the bus angles by searching (default).

BUS_REFERENCE_ANGLES 3 Set line-branch angles as zero. Recompute transformer angles with high voltage leading low voltage by 30 deg for delta-wye connections. Then derive the bus angles by searching.

BUS_REFERENCE_ANGLES 4 The same as 3 except that high voltage lags low voltage by 30 deg for delta-wye connections.

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None of these choices of angles changes the CAPE database. Also, the choice does not affect data re-exported to ANAFAS. You can use the macro BREF as an abbreviation for BUS_REFERENCE_ANGLES. For example, to compute all the bus and transformer angles in CAPE, enter BREF 3 or BREF 4. It is more accurate to choose one consistent rule (3 or 4) than to ignore reference angles (0). If the actual transformers include some leading high-voltage buses and others lagging, this rule will make some bus angles differ from the actual values by a multiple of 60 degrees. This will probably cause no harm because the difference is equivalent to a phase rotation by +/- 120 degrees and a possible change in sign. It affects all the voltages and currents in a region of the network between transformers. For example, phase voltages (Va, Vb, Vc) and currents (Ia, Ib, Ic) are replaced by (-Vb, -Vc, -Va) and (-Ib, -Ic, -Ia) when the positive-sequence quantities are rotated by 60 degrees. Provided the relays treat all phases equally, the relay operations and settings will be computed correctly whatever rule is chosen. In other words, CAPE will tolerate a 60-degree error but not a 30-degree error. If the total change in angle around a loop is not zero, one or more transformer winding types are not correct, and CAPE prints warning messages. These may indicate that iANAFAStoDB cannot find all the wye and delta windings with the data available. Use the list of branches to find data errors. 7. Series Capacitor with MOV Protection For a series capacitor with a parallel MOV voltage limiter, ANAFAS data has two records: one in the branch data with X1 <0 and one in a special section for the MOV device. CAPE reads both records and creates a single record in its Series Capacitor data. This has the branch reactance (negative), the threshold conductive current (IPR amps), and the energy to trigger (EMAX MJ/phase). CAPE does not store the IMAX and PMAX limits. The CAPE Series Capacitor form has an additional option of Spark Gap Protection, with the same threshold current IPR. Reference [1]. "Anafas Programa De Análise De Faltas Simultâneas" Versão 4.3 - Abr/06 Manual Do Usuário, CEPEL - Centro de Pesquisas de Energia Elétrica, - Rio de Janeiro, Brasil; 2006

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Transferring Aspen OneLiner Network Data to a CAPE

Database The CAPE program to transfer an Aspen OneLiner format network data file to an empty CAPE database is located in |CapeHomeDir|\progs, and is named iAspentoDB.exe. To transfer data to an empty database, please perform the following steps. 1. Prepare a directory where you wish the converted data to reside. These

instructions assume \My_Data. 2. Click Start | Programs | CAPE | Data Conversion | AspenToDB. This window

will appear:

3. Network data file: Specify the location and name of your Aspen DXT data file; it is easiest to use the “?” button for this.

4. Template gdb: Select the CAPE database file to be used as a template for your

new database. Typically this will be either \cape\dat\cape_starter.gdb or \cape\dat\empty_starter.gdb.

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5. Target gdb: Use the “?” button to search to the directory where the new database

is to be created and enter the desired name in the Windows form and click “Open.” If a file of this name already exists, it will be overwritten by a copy of the Template. If the file does not exist, one will be created by copying the Template.

6. Starting bus number: Aspen requires unique bus names rather than unique bus

numbers. However, Aspen buses may have numbers. CAPE will use the Aspen number for any bus that has one already. Insert here the starting number you want CAPE to use when it needs to assign a bus number.

7. Minimum branch impedance: Aspen does not support the concept of a bus tie, i.e.

a zero-impedance switch. Instead, such switches are often represented in Aspen by branches of low impedance. Specify here the threshold at or below which the CAPE conversion program should replace a branch by a bus tie. Enter 0.0 if no such conversion is to be done.

8. Extra output to log file: The CAPE conversion programs all write status, warning,

and error messages as appropriate during the conversion process. You can limit these messages to only the most important ones if you leave this box unchecked.

9. Infinite impedance: Network reductions that were done previously may have

produced branches of very large impedance. These can be ignored if you specify a threshold impedance here.

10. Treat 2-wdg transformers with circuit 99 as equivalent lines: Sometimes a branch

with circuit 99 is intended to indicate an equivalent branch. CAPE has a branch type field in its database record that can be set to properly identify the branch.

11. Click Begin Conversion to start the data transfer process. You can now watch as AspentoDB reads the network data and adds it to the database. A permanent log file, log_file.txt, is created in the working directory and will contain all information written to the screen. When AspentoDB is finished, your new database is ready to use with CAPE. You should review the log file to make sure no errors occurred. If any problems arise during the conversion, re-run the conversion with the box “Extra output to log file” checked. You may get an indication of what is wrong and at least you will know the last line read from the data file before the error occurred.

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Transferring Aspen OneLiner Diagrams to a CAPE Graphics File

The CAPE program to transfer an Aspen OneLiner format graphical diagram to a CAPE format graphics file is located in |CAPEHomeDir|\progs, and is named iOLRtoGF.exe. To transfer the graphic, please perform the following steps. 1. You must have a CAPE database representing the same network as the Aspen

OLR file. Converting the network data to CAPE is described immediately above in this document. If you have not performed this step, you must do so before continuing to step 2.

2. Execute the program |CapeHomeDir|\progs\iOLRtoGF.exe. This window will appear:

Click the tab “Create CAPE Graphics File.”

3. Source OLR File Name: Specify the location and name of your Aspen OLR data file; it is easiest to use the “…” button for this.

4. CAPE Database: Select the CAPE database file to use as a reference during the graphics conversion. The CAPE database is needed to translate the unique bus identifiers used in Aspen (bus_name+base_kV) into the unique bus identifier used in CAPE (bus_number).

5. Output Graphics File Name: Use the “…” button to search to the directory where the new graphics file is to be created and enter the desired file name. Typically, the same directory and file name as the CAPE database is used, but with a “.gf” file extension. You are free to use a different name if you prefer.

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6. If desired, you can restrict the diagram conversion to buses above a certain kV level. Use the “Omit buses below” checkbox for this.

7. If desired, you can restrict the diagram conversion to a single AREA or ZONE. Use the “Filter buses by AREA or ZONE” checkbox for this.

8. CAPE Graphics File Version: Choose the highest version number available. If your version of CAPE rejects the graphics file later, run this conversion program again and choose a lower version number.

9. Click OK; Create Graphics File to start the data transfer process. During the conversion, various progress pop-ups will appear to show the status of the conversion. When iOLRtoGF is finished, your new graphics file will be ready for use with CAPE.

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Transferring Aspen OneLiner Relays to a CAPE Database The CAPE program to transfer Aspen OneLiner format relays to a CAPE database is located in |CAPEHomeDir|\progs, and is named iOLRtoGF.exe. To transfer the relays, please perform the following steps. 1. You must have a CAPE database representing the same network as the Aspen

OLR file. Converting the network data to CAPE is described above in this document in the section “Transferring Aspen OneLiner Network Data to a CAPE Database.” If you have not performed this step, you must do so before continuing to step 2.

2. Execute the program |CapeHomeDir|\progs\iOLRtoGF.exe. This window will appear:

Click the tab “Copy Relays to CAPE.”

3. Source OLR File Name: Specify the location and name of your Aspen OLR data file; it is easiest to use the “…” button for this.

4. CAPE Database: Select the CAPE database into which you would like to copy the relays.

5. Source RLY File Name: Specify the location and name of your Aspen RLY data file; it is easiest to use the “…” button for this. The RLY file contains the time-current curves used by the overcurrent relays in your OLR file. This file is required if you select the option “Copy Overcurrent Relays to CAPE.”

6. Options: “Copy Overcurrent Relays to CAPE” – When checked, overcurrent relays will be copied from the OLR file to the CAPE database. ”Copy Distance Relays to CAPE” – When checked, distance relays will be copied from the OLR file to the CAPE database.

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”Assign Default Contact Logic” – When checked, default contact logic will be assigned to the relay elements in CAPE such that the operation of any element will be sufficient to issue a trip signal to the local breaker. This is the simplest way to set up your data for System Simulator studies, although manual “tweaking” will still be needed later.

7. Click OK; Copy Relays to CAPE Database to start the data transfer process. During the conversion, various progress pop-ups will appear to show the status of the conversion. When iOLRtoGF is finished, your CAPE database will be populated with relays which can be viewed using DBE or Coordination Graphics. If you chose to assign default logic, your database should be ready for System Simulator studies.

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Transferring DIgSILENT Data to a CAPE Database This conversion program has two modes of operation: adding data to an empty database and modifying selected data in an existing database. Mode 1 is used to load an empty CAPE database with the contents of a problem file (*.pbm). The problem file should contain all of the network equipment, including the maximum number of parallel lines and machines at a bus. Only equipment that is already in the database can be updated during mode 2. Substation names can be pulled from an existing database or automatically generated.

Follow these steps to use the DIgSILENT to DB conversion program. You will need up to four files: the master DIgSILENT library file (*.dig), the DIgSILENT problem file (*.pbm), an empty database to add the data to (created for you based on a template you specify), and, optionally, an existing database containing valid substation names. 1. Prepare a directory where you wish the converted data to reside. These

instructions assume \cape\dat.

2. Click Start | Programs | CAPE | Data Conversion | DigSilentToDB. This window will appear:

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3. System database: Specify the location and name of your DIgSILENT .dig file; it is easiest to use the “?” button for this.

4. Problem file: Specify the location and name of your DIgSILENT .pbm file.

5. Conversion Mode: Decide whether you are using Mode 1 (loading an empty database) or Mode 2 (modifying an existing database with changes from the problem file).

6. Substation Names Mode: Decide whether you want the program to create new substation names or use names from an existing database.

7. Substation gdb: If you chose to transfer existing substation names, specify here the database containing those names.

8. Template gdb: If you chose above to start with an empty database, select the CAPE database file to be used as a template for your new database. Typically this will be either \cape\dat\cape_starter.gdb or \cape\dat\empty_starter.gdb.

9. Target gdb: If a new database is being created, use the “?” button to search to the directory where that new database is to be created and enter the desired name in the Windows form. If an existing database is to be modified, specify it here.

10. Click Begin Conversion to start the data transfer process.

You can now watch as DIgSILENTtoDB reads the master and problem files and adds the network to the database. A permanent log file, log_file.txt, is created in the working directory that contains all information written to the screen. When DIgSILENTtoDB is finished, your new database is ready to use with CAPE. Online and Offline categories are created. You should review the log file to make sure no errors occurred. If any problems arise during the conversion, re-run the conversion with the box “Extra output to log file” checked. You may get an indication of what is wrong and at least you will know the last line read from the data files before the error occurred. Once you have a populated CAPE database, you can use mode 2 to modify selected data in that database. You will need three files; the master DIgSILENT library file (*.dig), the DIgSILENT problem file (*.pbm) and the populated CAPE database. The data fields that will be modified are: Bus Data - online status, prefault voltage magnitude and desired voltage Load Data - online status, P and Q Generator Data - online status, Pgen, Qgen, Qmax, Qmin and controlled bus Fixed Shunt Data - online status Switched Shunt Data - online status and initial connected B Lines - online status Transformers - online status, LTC tap and controlled bus number

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Transferring EII Data to a CAPE Database The CAPE program to transfer an Electrocon PSA Short Circuit format network data file to an empty CAPE database is located in |CapeHomeDir|\progs, and is named iEIItoDB.exe. To transfer data to an empty database, please perform the following steps. 1. Prepare a directory where you wish the converted data to reside. These

instructions assume \cape\dat. 2. Click Start | Programs | CAPE | Data Conversion | EIIToDB. This window

will appear:

3. Network data file: Specify the location and name of your Electrocon data file; it is easiest to use the “?” button for this.


5. Target gdb: Use the “?” button to search to the directory where the new database is to be created, enter the desired name in the Windows form and click “Open.” If a file of this name already exists, it will be overwritten by a copy of the Template.

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If the file does not exist, one will be created by copying the Template.

6. Extra output to log file: The CAPE conversion programs all write status, warning, and error messages as appropriate during the conversion process. You can limit these messages to only the most important ones if you leave this box unchecked.

7. Click Begin Conversion to start the data transfer process. You can now watch as EIItoDB reads the network data and adds it to the database. A permanent log file, log_file.txt, is created in the working directory that contains all information written to the screen. When EIItoDB is finished, your new database is ready to use with CAPE. You should review the log file to make sure no errors occurred. If any problems arise during the conversion, re-run the conversion with the box “Extra output to log file” checked. You may get an indication of what is wrong and at least you will know the last line read from the data file before the error occurred.

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Transferring FAULTY Data to a CAPE Database The CAPE program to transfer an Energy Australia FAULTY Short Circuit format network data file to an empty CAPE database is located in |CapeHomeDir|\progs, and is named iFaultYtoDB.exe. To transfer data to an empty database, please perform the following steps. 1. Prepare a directory where you wish the converted data to reside. These

instructions assume \cape\dat. 2. Click Start | Programs | CAPE | Data Conversion | FaultYToDB. This

window will appear:

3. Network data file: Specify the location and name of your FAULTY data file; it is easiest to use the “?” button for this.


5. Target gdb: Use the “?” button to search to the directory where the new database is to be created, enter the desired name in the Windows form and click “Open.” If a file of this name already exists, it will be overwritten by a copy of the Template. If the file does not exist, one will be created by copying the Template.

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7. Click Begin Conversion to start the data transfer process. You can now watch as FaultYtoDB reads the network data and adds it to the database. A permanent log file, log_file.txt, is created in the working directory that contains all information written to the screen. When FaultYtoDB is finished, your new database is ready to use with CAPE. You should review the log file to make sure no errors occurred. If any problems arise during the conversion, re-run the conversion with the box “Extra output to log file” checked. You may get an indication of what is wrong and at least you will know the last line read from the data file before the error occurred.

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Transferring PSLF Data to a CAPE Database

The CAPE program to convert General Electric PSLF positive and zero sequence network data files to an empty CAPE database is located in |CapeHomeDir|\progs and is named iPSLFtoDB.exe. To transfer data to an empty database, please perform the following steps. 1. Prepare a directory where you wish the converted data to reside. These

instructions assume \cape\dat. 2. Click Start | Programs | CAPE | Data Conversion | PSLFToDB. This

window will appear:

3. PF data file: Specify the location and name of your positive sequence file. This file typically has “epc” as the extension. It is easiest to use the “?” button for this.

4. SC data file: Specify the location and name of your zero sequence file. It may have the extension “seq”. This file is optional. If you do not supply one, the zero sequence impedances will be set to three times the positive sequence impedances.


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6. Template gdb: Select the CAPE database file to be used as a template for your

new database. Typically this will be either \cape\dat\cape_starter.gdb or \cape\dat\empty_starter.gdb.


8. Click Begin Conversion to start the data transfer process. You can now watch as PSLFToDB reads the network data and adds it to the database. A permanent log file, log_file.txt, is created in the working directory that contains all information written to the screen. When PSLFToDB is finished, your new database is ready to use with CAPE. You should review the log file to make sure no errors occurred. If any problems arise during the conversion, re-run the conversion with the box “Extra output to log file” checked. You may get an indication of what is wrong but at least you will know the last line read from the data file before the error occurred.

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Transferring PSS/E Data to a CAPE Database

The CAPE program to convert PSS/E positive and zero sequence network data files to an empty CAPE database is located in |CapeHomeDir|\progs and is named iPSSEtoDB.exe. To transfer data to an empty database, please perform the following steps. 1. Prepare a directory where you wish the converted data to reside. These

instructions assume \cape\dat. 2. Click Start | Programs | CAPE | Data Conversion | PSSEToDB. This

window will appear:

3. Raw data file: Specify the location and name of your positive sequence file. This file typically has “raw” or “rawd” as the extension. It is easiest to use the “?” button for this.

4. 0-Seq data file: Specify the location and name of your zero sequence file. It may have the extension “seq”. This file is no longer optional.

5. Template gdb: Select the CAPE database file to be used as a template for your new database. Typically this will be either \cape\dat\cape_starter.gdb or

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\cape\dat\empty_starter.gdb.


7. PSSE Version: Choose the PSS/E version number of the program that created your .raw and .seq data files. It may be from 23 to 30 at present. Failure to get this right usually results in program failure. Just try again with a different version number.

8. Length Units: Choose the units to be used for line lengths. Line lengths are always stored in the database as km, but your data file may have different units.

9. System Frequency: The system frequency is not used during the conversion process but is written to the database.

10. Create Substations. PSS/E does not support the substation data construct. Check this box if you want CAPE to create substation names (based on bus names) for you.


12. Special switched shunt treatment: You can convert switched shunts to fixed shunts under the following conditions if this box is checked: • The data field MODSW = 0; i.e. the shunt is not allowed to move. • There is only one block (N1 = 1 and N2-N8 = 0). If the initial admittance (BINIT) equals the first block (B1), the shunt will be placed in the online category with a value of B1. If not (BINIT is most likely 0), the shunt will be placed in the offline category with a value of B1.

13. Convert zero impedance lines to bus ties: PSS/E does not support the concept of a bus tie, i.e. a zero-impedance breaker or disconnect switch. Instead, such devices are often represented in PSS/E by branches of low impedance. Set the “Zero impedance line threshold” at or slightly above the level below which the CAPE conversion program should replace a branch by a bus tie. Enter 0.0 if no such conversion is to be done. Most users may ignore the “Impedance of Disconnect Switches.” A line which would be converted to a bus tie will have its Tie Type set to “Disconnect Switch” if the series x value exactly matches the value specified in the “Impedance of Disconnect Switches” box. If the series x value does not match, the tie type will be set to “Logical Breaker”. In CAPE, the two bus tie types are treated equally, but the OneLine Diagram module can show different symbols. In general, logical

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Transferring Data

breakers would have protection data, but disconnect switches would not. This feature is only available if the schema of the template database is 3.48 or greater. The value entered in the “Impedance of Disconnect Switches” box should be less than the value entered in the “Zero impedance line threshold” box. Special note for users converting data from the Integral program: You must use the “Convert zero impedance lines to bus ties” option and you must set the “Zero impedance line threshold” to a number slightly larger than 0.00001. You may ignore the “Impedance of Disconnect Switches” value for now. When the lines are saved to the database, any line with an impedance less than the threshold will be saved as a bus tie. Any bus tie that is connected between a detailed primary bus and a conventional bus will be saved with a “Tie Type” of “Disconnect Switch.”

14. Bus voltage angles contain YD transformer shifts: CAPE needs to store separately the implicit angle shifts across wye-delta transformer windings. In PSS/E, these angles may be buried within the total bus angle data field especially if the PSS/E data represents a solved power flow case. If you check this box, CAPE will extract these implicit angles when the database is read the first time.

15. Click Begin Conversion to start the data transfer process. You can now watch as PSSEtoDB reads the network data and adds it to the database. A permanent log file, log_file.txt, is created in the working directory that contains all information written to the screen. When PSSEtoDB is finished, your new database is ready to use with CAPE. You should review the log file to make sure no errors occurred. If any problems arise during the conversion, re-run the conversion with the box “Extra output to log file” checked. You may get an indication of what is wrong and at least you will know the last line read from the data file before the error occurred. Implementation Notes 1. CAPE lets you choose one set of power flow line ratings to export: rates 1 to 3 or 4 to 6. Enter "RATE_SET 1" or "RATE_SET 2" (no quotes) on the command line or in your personal configuration file (|CapeHomeDir|\dat\cape.cfg). 2. The CAPE PI and N-Circuit transformer models are converted to the PSS/E two-winding or three-winding models. Off-nominal transformer taps are retained. Zigzag windings are converted to equivalent ungrounded wye windings (for +/- sequence quantities) together with zero-sequence bus shunts. 3. CAPE eliminates neutral nodes from the PSS/E data using the formulae in [1] for two-winding and three-winding transformers. Hence CAPE ensures correct zero-sequence currents. We have avoided using the PSS/E data fields (RG, XG) for grounding impedance because the PSS/E manual does not give enough details of the three-winding transformer models. 4. Transformers sharing neutral nodes are not modeled accurately by PSS/E (as of Version 30), so CAPE makes an approximation in the PSS/E data as follows: if N transformers share one neutral node with one shunt impedance Z, they are each

25

Transferring Data

given a separate grounding impedance of N times Z. A transformer winding connected to a neutral branch instead of a shunt is approximated as solidly grounded, since PSS/E does not model neutral networks in detail. 5. When you import data from PSS/E, phase angles (+ or - 30 deg) from delta-wye connections are placed in the Bus Data, and CAPE automatically sets matching angles to connected buses at the same voltage level. 6. If you have previously imported PSS/E data into CAPE and now export the CAPE data back to PSS/E, CAPE overwrites all the two-character line ID codes with the CAPE circuit numbers. The CAPE circuit numbers are always unique between two buses, but it is difficult to detect duplicate line IDs after a CAPE user has added parallel branches, and the duplicates might cause PSS/E to fail. Generator and load IDs from PSS/E are retained, however. 7. Version 29 has an additional field "RMIDNT" in the Switched Shunt Data, and otherwise uses the same format as Version 28. Versions 27-29 all use separate transformer and non-transformer records. You must choose the correct version when converting data. The following messages may indicate errors in the CAPE transformer data: *** Error: + seq XFMR impedance missing; using INFINITE *** Ignoring transformer with more than three windings *** Warning: ignoring 0-seq series reactance at XFMR Delta *** Warning: missing PI-model 0-seq shunt in Delta-Wye XFMR *** Warning: ignoring shunt of PI-model Wye-Wye XFMR *** Warning: 2 separate neutral nodes in 3-wdg YYY XFMR; PSS/E allows only 1 or 3; using solid grounding. *** Warning: 3 XFMRs use neutral node; using a separate neutral node for each XFMR. Reference [1] Electrical Transmission and Distribution Reference Book, Fourth Edition. Westinghouse Electric Corporation, 1964.

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Transferring Data

Transferring PSS/U Data to a CAPE Database The CAPE utility program to transfer a PSS/U network data file to an empty CAPE database is located in |CapeHomeDir|\progs and is named iPSSUtoDB.exe. To transfer data to an empty database, please perform the following steps. 1. Prepare a directory where you wish the converted data to reside. These

instructions assume \cape\dat. 2. Click Start | Programs | CAPE | Data Conversion | PSSUToDB. This

window will appear:

3. Network data file: Specify the location and name of the mandatory PSS/U input file. It is easiest to use the “?” button for this.

4. Construction Dictionary #1. If branch impedances are to be calculated based on

line lengths and conductor codes, you must specify the location and name of the required conductor file. If your data file is stand-alone, just leave this field blank. You can have up to two conductor files. If your data file requires only one conductor data file, leave the next field blank.

5. Construction Dictionary #2. Specify the location and name of an optional second file of standard line construction names and impedances. If not needed, leave this blank.

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Transferring Data

6. Machine Data Dictionary. Specify the location and name of your optional PSS/U file of standard machine impedances. Leave blank if your data file is stand-alone.

7. Initial bus number. Since the PSSU data file does not contain bus numbers, and

CAPE requires them, consecutively increasing numbers will be automatically generated by PSSUtoDB. You can enter the initial bus number, typically 1.




11. Click Begin Conversion to start the data transfer process.

You can now watch as PSSUtoDB reads the network data and adds it to the database. A permanent log file, log_file.txt, is created in the working directory that contains all information written to the screen. When PSSUtoDB is finished, your new database is ready to use with CAPE. You should review the log file to make sure no errors occurred. If any problems arise during the conversion, re-run the conversion with the box “Extra output to log file” checked. You may get an indication of what is wrong and at least you will know the last line read from the data file before the error occurred.

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Transferring Data

Transferring CAPE data to an External Data File The network model as read by the CAPE Executive | File | Build_SC_Network command can be transferred to any of the three supported data formats two different ways. Data files can be created in the CAPE Executive and Short Circuit Reduction modules. A. Executive Module

From the Executive module, the entire network model can be saved by clicking File | Save | Network Data. The four options are: • To EII Format - selection of this option will cause a user-specified file to be created

containing the entire network model in Electrocon PSA SC format. • To PSSE Format - selection of this option and a subsequent PSS/E version number

will cause a pair of user-specified files to be created containing the entire network model in PTI PSS/E format. The positive sequence file must be created, but the zero sequence file is optional (although it is required for short circuit studies). Simply select the “Cancel” button on the file dialog box and it will not be created. The exported file will contain internal bus numbers, no override of ZR and ZX, and will use a bus tie impedance of 0.00001 p.u. For version 29, you can optionally choose to save the network for a specific bus set. All buses in the set and everything connected to them will be saved.

• To Aspen Format - selection of this option will cause a user-specified file to be

created containing the entire network model in Aspen Oneliner format.

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Transferring Data

• To ANAFAS Format - selection of this option will cause a user-specified file to be created containing the entire network model in ANAFAS format. See “ANAFAS Implementation Notes” below.

B. Short Circuit Reduction Module

From the Short Circuit Reduction module, either before or after a reduction has taken place, the remaining network model can be saved by clicking File | Save | Network Data. The four options are: • To EII Format - works exactly as it does from the Executive module except that

the network may be reduced first. • To PSSE Format - selection of this option and a subsequent version number will

cause a pair of user-specified files to be created containing the network model in PTI PSS/E format. The positive sequence file must be created, but the zero sequence file is optional (although it is required for short circuit studies). Simply select the “Cancel” button on the file dialog box and it will not be created.

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Transferring Data

You have control over the bus numbers saved, internal or external, and the bus tie impedance. You also have control over which generator impedances are saved for ZR and ZX. These options are set on the Short Circuit Reduction Local Options popup. For version 29, you can optionally choose to save the network for a specific bus set. All buses in the set and everything connected to them will be saved.

• To Aspen Format – works exactly as it does from the Executive module except that

the network may be reduced first.

• To ANAFAS Format – works exactly as it does from the Executive module except that the network may be reduced first. Please refer to the following “ANAFAS Implementation Notes.”

ANAFAS Implementation Notes Because CAPE needs more detail than ANAFAS, some CAPE data are simplified for export to the ANAFAS format. 1. CAPE exports to ANAFAS V4.2 format only, at this time.

2. Negative-sequence impedances are treated as equal to the positive-sequence

values, since ANAFAS does not separate them. 3. ANAFAS V4.2 supports only four digits for the bus number, so the highest

possible ANAFAS bus number is 9998 (9999 being reserved for the 'end of data' indicator). CAPE, however, supports up to six digits. If you do nothing, CAPE will automatically substitute new numbers in the ANAFAS file for any CAPE numbers that exceed 9998. This is the easiest way to export a large case.

Alternatively, CAPE DBE allows you to specify an external bus number on the External Formats tab of the Bus Data form. When you wish to export these numbers to ANAFAS, set the option "External_Numbers" ON in the Short-Circuit Reduction Preferences form. Alternatively, you may manually replace the CAPE bus number using the Database Editor. After you read ANAFAS data back into CAPE, the CAPE buses will have the 4-digit ANAFAS numbers.

3. If you have previously imported ANAFAS data into CAPE and now export the

CAPE data back to ANAFAS, CAPE keeps the ANAFAS circuit numbers where they are valid (unique and non-zero between two buses).

4. CAPE transformer models are converted to ANAFAS as branches having

appropriate ANAFAS bus types, namely external (type 0) - external for two-winding models and external - internal (type 1) for three-winding models. In

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Transferring Data

CAPE, the zero-sequence shunt of a transformer model is stored with the CAPE branch data. In ANAFAS, it is represented as a separate shunt and, hence, is extracted from the CAPE PI transformer model.

5. Transformers with three windings are modeled with a three-branch "Tee" model.

If the CAPE data uses the N-Circuit model, the ANAFAS export procedure derives an equivalent "Tee" with an extra "type-1" center bus. Transformers with four or more windings are omitted from the ANAFAS file at present. In a future version, CAPE will convert its N-Circuit model to a branch model. This will include four extra internal buses per transformer.

6. Neutral points on transformers and shunts (generators or loads) are treated as

solidly grounded. 7. All prefault voltages are saved as 1 perunit at phase angle zero. Bus reference

angles are not saved because the ANAFAS format has no place for them, but CAPE can re-derive them when it reads an ANAFAS data file.

CAPE cannot now transfer a Power Flow solution to ANAFAS. Therefore you should build the CAPE network using the initial condition:

"Without Load Currents (Classical Short Circuit)" on the CAPE Executive Session Setup form.

8. Line-charging capacitance, loads, and other passive shunts are ignored in the

ANAFAS export even if they have been read into CAPE. Grounding transformers (shunts with zero-sequence admittance only) are exported, with the same resistance and reactance as in CAPE. (The flow chart on page A6 of the ANAFAS manual is wrong; the resistance does not have to be zero.) We will add the loads and passive shunts to the ANAFAS file in a future release if necessary.

9. Off-nominal transformer taps are ignored in the export to ANAFAS.

Transformer winding turns are taken as proportional to the network bus base voltages, so that the perunit prefault voltages on the windings are equal.

10. Bus ties are replaced by low-impedance branches (0.0001 + j0.0001 perunit).

11. MOV protection on series capacitors is ignored when the data are exported (at

this time).

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Documents

DataTransfer.pdf