Download User manual 1

PCFLO Version 5.2, http://www.ece.utexas.edu/~grady/, July 28, 1998
PCFLO Version 5.2 User Manual
July 28, 1998
Prof. Mack Grady
Department of Electrical & Computer Engineering
University of Texas at Austin
Austin, TX 78712
Phone: 512 - 471 - 5231
FAX: 512 - 475 - 8198, or 512 - 471- 5532
email: [email protected]
http://www.ece.utexas.edu/~grady/
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PCFLO Version 5.2, http://www.ece.utexas.edu/~grady/, July 28, 1998
Setup Instructions
PCFLO performs loadflow, short circuit, and harmonics analysis. It reads
column-formatted, comma-separated (CSV), or tab-separated (TSV) data.
CSV/TSV data make it easy to use Microsoft Excel for preparing your input
data and examining your output results. Excel’s sorting capabilities are
especially helpful in reviewing, for example, total harmonic distortion at
busses, or in finding transmission lines with overloads or busses with high
or low voltages.
You will find that HOWDY.ZIP contains some column- formatted files, and
some comma-separated or tab-separated (CSV/TSV) data files. Four CSV
header files are also enclosed that you may find helpful when using Excel
(files BDAT.HDR, LDAT.HDR, ADAT.HDR, SPECTRA.HDR). These
header files should be placed at the top of CSV/TSV input data to describe
the content of the spreadsheet columns.
For your information, PCFLO treats any row in a CSV/TSV input file that
has a colon in column 1 as a comment line.
Setup Instructions:
1. Establish a new directory named PCFLO,
2. Download HOWDY.ZIP into it,
3. Pkunzip HOWDY.ZIP.
Disclaimer
Professor Mack Grady and the University of Texas at Austin give no
warranty that all errors have been eliminated from this software. Neither
Professor Grady nor the University of Texas at Austin shall be liable for
direct, indirect, or consequential losses, damages, costs, expenses, claims,
or fees of any nature or kind resulting from any deficiency in this software.
Professor Mack Grady, Department of Electrical & Computer Engineering,
University of Texas at Austin, Austin, TX 78712. Phone: 512-471-5231,
FAX: 512-475-8198, email: [email protected].
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PCFLO Version 5.2, http://www.ece.utexas.edu/~grady/, July 28, 1998
Instructions for Performing Loadflow, Short Circuit, Harmonics, and
Motor Starting Calculations
Program PCFLO is common to loadflow, short circuit, and harmonics
calculations. PCFLO (500 bus version) contains a simple dialog box where
you specify the path and extension of the input files. PCFLOH is a 500 bus
version, tailor-made for harmonics studies. Program HARMPLOT is used
in harmonics studies to view voltage and current waveforms as well as
network impedances.
The information in file OPTIONS instructs PCFLO to perform loadflow
(including motor starting), short circuit, or harmonics calculations.
Input data for PCFLO can be either column formatted, comma-separated, or
tab-separated. Most output files are formatted and comma-separated.
Comma-separated and tab-separated data files are easily viewed and edited
with Microsoft Excel.
PCFLO always reads data directly from files ADAT, BDAT, LDAT,
OPTIONS, and SPECTRA. Their content and structures are explained in
this document.
Loadflow
Step 1:
Copy file OPTIONS.LF to your file OPTIONS and make any
necessary changes.
Step 2:
Copy the loadflow bus and line/transformer into files BDAT and
LDAT, respectively. If area interchange data are desired,
include them in file ADAT. Otherwise, ADAT is unnecessary
and must be deleted.
Step 3:
Execute PCFLO (i.e., PCFLO.EXE).
Step 4:
The loadflow "printout" is found in file OUT1 and OUT4. File
VSOLN contains the solved bus voltages. File ISOLN contains
branch currents. File OUT5 contains a useful summary of both
branch currents and bus voltages.
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PCFLO Version 5.2, http://www.ece.utexas.edu/~grady/, July 28, 1998
Short Circuit
Step 1:
Copy file OPTIONS.SC to your file OPTIONS and make any
necessary changes.
Step 2:
BDAT must contain the conventional loadflow data plus, at a
minimum, the positive sequence subtransient reactances of the
swing bus and other generators and motors. If negative and zero
sequence data are provided for generators and motors, including
neutral grounding impedances, then PCFLO will be able to
perform line-to-line and line-to-ground fault calculations (as well
as three-phase fault calculations).
Similarly, LDAT must contain conventional loadflow data. Also,
if line-to-line and line-to-ground fault calculations are to be made,
then LDAT must include negative and zero sequence data, such as
transformer connections, phase shifts, and neutral grounding
impedances.
Step 3:
Execute PCFLO. The "printout" is found in files OUT1 and
OUT2. PCFLO builds impedance matrices ZBUS0, ZBUS1, and
ZBUS2 for zero/positive/negative sequences, respectively.
ZBUS1 is always built, but ZBUS0 and ZBUS2 are built only if
sufficient data are provided in BDAT and LDAT.
While in PCFLO, enter the bus number and complex fault
impedance, in percent. Enter as many combinations of bus
numbers and fault impedances as you like, one at a time.
Step 4:
The results are found in file FREP. FREP lists all the information
for a three-phase fault, then a phase-b-to-c line-to-line fault
(through
), then a phase-a line-to-ground fault (through
).
Full Harmonic Study
A full harmonic study injects harmonic load currents and calculates
harmonic network bus voltages, branch currents, and voltage distortion.
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PCFLO Version 5.2, http://www.ece.utexas.edu/~grady/, July 28, 1998
Step 1:
Copy file OPTIONS.HS to your file OPTIONS and make any
necessary changes.
Step 2:
BDAT and LDAT must contain the same data needed for fault
studies. In addition, BDAT must contain the characteristics of any
connected nonlinear loads.
Step 3:
User-specified harmonic current spectra for nonlinear loads can be
placed into file SPECTRA if needed.
Step 4:
Execute PCFLO (or PCFLOH). A loadflow is automatically
invoked to help identify data errors.
Step 5:
The "printout" is found in files OUT1, OUT2, and OUT3. PCFLO
builds files VSOLN and ISOLN that contain the Fourier series of
bus voltages, line/transformer/shunt element currents, and
nonlinear device currents (load convention). The values are given
in rms percent. PCFLO also builds file THDV which tabulates
network voltage distortions.
Step 6:
Graphical results can be viewed in the background of PCFLOH, or
separately by executing program HARMPLOT. Use HARMPLOT
(within Windows only) and its self explanatory menu-selects to
view bus voltages and nonlinear device current waveforms (both
in file VSOLN), as well as branch currents (in file ISOLN).
To execute HARMPLOT, first select its icon. Then, under the File
Open option, choose file type ISOLN or VSOLN. ISOLN
contains branch currents, and VSOLN contains bus voltages and
nonlinear load currents. Select either of these files and plot the
results on the screen. Up to four waveforms may be plotted on
one graph. Using the Export option, plots may be saved as *.BMP
files for printing with Windows Paintbrush.
(Note: Files ISOLN.WG and VSOLN.WG are provided as
samples.)
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PCFLO Version 5.2, http://www.ece.utexas.edu/~grady/, July 28, 1998
Harmonic Impedance Scan
A harmonic impedance scan computes the Thevenin equivalent (i.e. driving
point) harmonic impedances of network busses.
Step 1:
Copy file OPTIONS.HZ to your file OPTIONS, and make the
necessary changes according to Table 4.
Step 2:
BDAT and LDAT must contain the same data needed for fault
studies. In addition, BDAT must contain the characteristics of any
connected nonlinear loads.
Step 3:
Execute PCFLO (of PCFLOH). A loadflow is automatically
invoked for either option to help identify data errors.
Step 4:
The "printout" is found in files OUT1, OUT2, and OUT3. PCFLO
builds the diagonal elements of either file ZBUS0, ZBUS1, or
ZBUS2, depending on which phase sequence is requested. The
values are given in percent. If desired, impedance scans can be
limited to nonlinear busses.
Step 5:
Graphical results can be viewed in the background of PCFLOH, or
separately by executing program HARMPLOT. Use HARMPLOT
(within Windows only) and its self explanatory menu-selects to
view the impedance matrix elements (magnitudes and phase
angles) for network busses (in files ZBUS0, ZBUS1, and ZBUS2,
for zero, positive, and negative sequences, respectively).
To execute HARMPLOT, first select its icon. Then, under the File
Open option, choose file type ZBUS. Select a ZBUS file and plot
the results on the screen. Up to four waveforms may be plotted on
one graph. Using the Export option, plots may be saved as *.BMP
files for printing with Windows Paintbrush.
(Note: File ZBUS1.WG is provided as a sample.)
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PCFLO Version 5.2, http://www.ece.utexas.edu/~grady/, July 28, 1998
Motor Starting
Step 1:
Copy file OPTIONS.LF to your file OPTIONS, and make the
necessary changes according to Table 1.
Step 2:
Copy the corresponding loadflow bus and line/transformer into
files BDAT and LDAT, respectively. If area interchange data are
desired, include them in file ADAT. Otherwise, ADAT should be
deleted.
Step 3:
Modify file LDAT so that the motor bus has a fixed series
impedance-to-ground branch. The FROM BUS of the branch is
the motor bus number, and the TO BUS is zero (i.e., ground).
Since the starting current for a motor is approximately five-times
the full-load run current, and at a very low power factor, the
impedance should be approximately:
Z
 R
X

P
, pf
 jX
,
where
pf
5  P
, R

X
5
,
and
are full-load motor power and power factor, respectively. The
impedance should be entered in percent.
Step 4:
Remove the motor P and Q load from file BDAT.
Step 5:
Execute PCFLO. The results are found in files OUT4 and
VSOLN. If the voltage at the motor bus falls below 80%, it may
not start.
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PCFLO Version 5.2, http://www.ece.utexas.edu/~grady/, July 28, 1998
Summary of PCFLO Data Files
ADAT:
Loadflow area input data. (PCFLO also creates temporary file
ADAT.TMP)
ASOLN:
Solved area data for loadflows.
BDAT:
Bus input data.
BDAT.TMP:
Unformatted bus data file built by PCFLO and read by
FAULTS.
BORDER:
File built by PCFLO that lists the busses in optimal order.
EXLOG:
Echo print of screen messages.
FREP:
Output for short circuit studies (produced by program
FAULTS).
ISOLN, VSOLN: Solved branch currents and bus voltages for loadflow
and harmonics studies. (Sine series format for Fourier
series)
LDAT:
Line and transformer input data.
LDAT.TMP:
Unformatted line and transformer data file built by PCFLO
and read by FAULTS.
OPTIONS: User input solution options.
OUT1, OUT2, OUT3:
Echo print of input data for loadflow, short circuit,
and harmonics, along with pertinent messages and
errors.
OUT4:
Loadflow output data.
OUT5:
Loadflow summary output used for wheeling analysis.
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PCFLO Version 5.2, http://www.ece.utexas.edu/~grady/, July 28, 1998
SPECTRA: User input harmonic current injection spectra. (PCFLO also
creates temporary file SPECTRA.TMP)
THDV:
Solved total harmonic voltage distortions for harmonics
studies.
ZBUS0, ZBUS1, ZBUS2:
Solved
zero/positive/negative
impedance
matrix elements for short circuit (rectangular
form) or harmonic studies (polar form), in
percent.
Prepared Input Data Files
(Note - always delete the old ADAT file before executing PCFLO)
18 Bus Distribution System for Harmonics Studies (Extension WG)
83 Bus Transmission System for Loadflow Studies (Extension COA)
5 Bus Distribution System for Harmonics Studies (Extension EL)
5 Bus Stevenson Loadflow Example (Extension S5)
6 Bus Stevenson Short Circuit Example (Extension S6)
9 Bus Stevenson Short Circuit Example (Extension S7)
36 Bus Industrial Short Circuit Example (Extension DP1)
232 Bus Distribution System for Harmonics Studies (Extension CHI)
Structure of Harmonic-Related Output Files
(Note - for loadflow studies, the formats of ISOLN and VSOLN are
different from below but are self-explanatory when viewing the files. For
short circuit studies, the ZBUS files are similar to below, but written in
rectangular form)
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PCFLO Version 5.2, http://www.ece.utexas.edu/~grady/, July 28, 1998
Commas separate the header lines and fields shown below to facilitate their
use with Microsoft Excel.
ISOLN
Data Field
(starting from
the left)
1
2
3
4
5
6
7
8
9
Description
Harmonic number
From bus number
To bus number
Circuit number
Current magnitude - percent
Current phase angle (sine reference) - degrees
From bus name (at the first opportunity only)
To bus name (at the first opportunity only)
Loading level - % of line rating (for
fundamental frequency only)
VSOLN
Data Field
(starting from
the left)
1
2
3
4
5
6
7
Description
Harmonic number
Bus number
Voltage magnitude - percent
Voltage phase angle (sine reference) - degrees
Nonlinear device load current magnitude percent
Nonlinear device load current phase angle
(sine reference) - degrees
Bus name (at the first opportunity only)
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PCFLO Version 5.2, http://www.ece.utexas.edu/~grady/, July 28, 1998
ZBUS0, ZBUS1, ZBUS2
Data Field
(starting from
the left)
1
2
3
4
5
6
7
Description
Harmonic number
From bus number
To bus number
Impedance magnitude - percent
Impedance phase angle - degrees
From bus name (at the first opportunity only)
To bus name (at the first opportunity only)
THDV
THDV contains a list of bus numbers with their corresponding names
and voltage distortions.
Appendix
The formats and structures of the input data files are given on the following
pages.
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