introduction to atp - may 16 2011v8

Introduction to the
Alternative Transients Program (ATP)
IEEE SPDC Spring Meeting
May 16, 2011
Gerald Lee
Christine Goldsworthy
Bonneville Power Administration (BPA)
Adapted from Anders Johnson’s Presentation, BPA:
Introduction to ATP for System Protection & Control, March 11, 2004
Objectives
• Present a powerful tool for steady state and transient
analysis of power systems
• Accelerate the learning curve
–
–
–
–
Introduction to features, applications, and functions of ATP
Tips to improve the user’s experience
Pitfalls to avoid
Demonstrations with simple circuits
Topics
Monday May 16, 2011
1:00 – 3:00 pm
Gerald Lee
1. Overview of the Alternative Transients Program
2. Getting Started
3. Using ATP Draw
4. Running ATP Simulations
5. Plotting and Analyzing Results
6. Modeling Basic Components
7. TACS (Transient Analysis of Control Systems)
8. User-Defined Components
9. Other Types of Simulations
Tuesday May 17, 2011 10:00 am – 12:00 pm Christine Goldsworthy
Chair - Tom Field, TF Meeting from 10:00am – 12:00pm
• Includes BPA ATP Studies on Separation effects
Overview of ATP
Background, programs, and applications
ATP Background
• ATP is a version of the Electromagnetic Transients Program
(EMTP)
– ATP was developed from the original BPA EMTP
• H. W. Dommel. “Digital Computer Solution of Electromagnetic Transients in
Single- and Multiphase Networks.” IEEE Transactions on Power Apparatus and
Systems. Vol. PAS-88, No. 4. Apr. 1969. pp 388-399.
• ATP users must sign a license agreement to use the program
– http://www.emtp.org
– http://www.eeug.org
– License is free, on the condition that users agree not to
participate in EMTP commerce
ATP Programs & Help
•
Different programs are used to generate, simulate, and analyze ATP
cases
– ATP: Computational engine for simulation
See: http://eeug.org/ or http://www.emtp.org/
– ATP Draw: Graphical preprocessor to ATP
See: http://eeug.org/ or http://www.elkraft.ntnu.no/atpdraw/
– ATP Analyzer: Plotting tool
See: http://eeug.org/
– PlotXY/Plotxwin: Plotting tools
See: http://eeug.org/
•
EEUG List Server – User Q&A
http://www.emtp.org/atplic.html#canamlic License
http://www.emtp.org/maillist.html Subscription
ATP
• Computational engine for electromagnetic transient simulation
– Developed by Dr. W. Scott Meyer and Dr. Tsu-huei Liu
– Solves linearized differential equations of system components with
numerical integration
– Trapezoidal method
• Input format: FORTRAN cards
– .atp files can be written with a text editor (card images) or
generated by ATP Draw (graphical interface)
– Case will not run if cards are not precisely formatted
• ATP Output format: .pl4 file, .lis file
Applications of ATP/EMTP
•
•
Time Domain Simulation
– Switching transients
• Circuit breaker transient recovery voltage (TRV)
• Capacitor, reactor, transformer and line switching
• Statistical performance
• Faults and series caps
– Over-voltage protection
• Lightning
– Relay settings
– Control systems
Frequency Scan
– Subsynchronous resonance (SSR)
– Harmonic resonance
Startup File
• Source of default Program setup parameters
• Look for “Startup.” in same folder as TPBIG.exe
Open Startup.txt
Startup File Parameter Issues
• MOSA Convergence Problems – Increase EPSTOP to 3
– ZNOLIM(2) to 3
– MAXZNO to 200
• Plotting Problems (Plotxy or Analyzer) – Change NEWPL4 to 1 (both work except no units)
– NEWPL4 = 0 Works with Analyzer not Plotxy
– NEWPL4 = 2 Works with Plotxy (good units) not Analyzer
• Disconnected Subnetworks being Grounded – Decrease EPSILN to 1D-12
– Or add a large resistor between object and ground
• Parameter Definitions
– See Rule Book Page 1E-7
ATP Draw
• Graphical preprocessor to ATP (ATP Draw)
– Programmed by Hans Hoidalen
– ATP Draw cases are stored as .acp files
– .atp files are generated from ATP Draw cases
• Many people find the ATP Draw interface easier to learn
and to use than FORTRAN cards
• ATP Draw is continually being improved
Open ATP Draw
ATP Draw Getting Started
•
•
•
•
•
•
Configuring ATP Draw
Short Cuts
Simulation Menu
Output Menu
Default Settings
Component Issues
Configuring ATP Draw
• Configure ATP Draw to run ATP (not
usually necessary)
–Tools->Options->Preferences
–Under the Programs heading for
ATP, browse to find the file
“C:\ATPDraw\runATP_W.bat”
• In the ATP Draw menu, select Tools ->
Save Options when finished:
Open Preferences
Program Shortcuts
•
Create shortcuts in ATP Draw to run other
programs
•
•
ATP -> Edit Commands
•
Shortcut to PlotXY for viewing waveforms
1) Click New
2) Type “PlotXY” in the Name field
3) Click Browse and locate the path of the .exe
file
4) Under Parameter, select “Current PL4”
Repeat this procedure to make a shortcut to ATP
Analyzer
Open Edit Commands
ATP Draw Simulation Menu
• Select File -> New to create a new case
• First, configure the simulation settings
– ATP -> Settings, or F3
• Example:
–Time domain simulation
–Time step of 1 ms
–Run the case for three 60 Hz cycles
(0.05 s)
• If you only want the phasor steady state
solution, then set Tmax = -1
•
•
•
•
XOPT = 60 (Inductors are in ohms)
COPT = 0 (Capacitors in microfarads)
EPSILON = 1E-12 or Change in Startup File
Freq = System Frequency
Open Settings
ATP Draw: Simulation Menu
• Inductances may be entered in mH or W
– Xopt = 0 L in mH
– Xopt = 60 L in W at 60 Hz
• Capacitances may be entered in mF or m-mho
– Copt = 0 C in mF
– Copt = 60 C in m-mho at 60 Hz
ATP Settings: Output Menu
• Print freq
– Solution points are written to .lis
file each “n” time steps.
• Plot freq
– Solution points are written to .pl4
file each “n” time steps
– Recommended to be an odd
number.
• Auto-detect simulation errors
–Display an error message if ATP
crashes
Open Output
Using ATP Draw
• Placing and moving components
• Single-phase vs. three-phase
• Nodes
• Comments, labels, and icons
Components
• Sources
–voltage, current
–ac, dc, ramp, surge
• Passive circuit elements
–linear & nonlinear R, L, C
–MOV
• Switches
–time-controlled, voltagecontrolled, statistical, power
electronics
• Transformers
–ideal, saturable
• Machines
–synchronous, induction, dc
• Transmission lines & cables
–lumped parameter (pi),
distributed parameter, line
constants
• TACS (Transient Analysis of
Control Systems)
–transfer functions, math
statements, logical operators
–sample and hold, time delay,
min/max, frequency meter
• User-defined
–MODELS, library files, groups
Open example <ALL.ACP> to see what is in the .SCL file
Open Right Click Menu
Placing Components
1) Right Click on the ATP Draw background to
open the component menu
2) Select the desired submenu
3) Left Click on the name of the desired
component
4) Move the component into the desired position
in the circuit
–
Left Click, hold the mouse button, and drag the
mouse to the desired location
Moving Components
• Left Click and drag the mouse
• Select a single component (Left Click)
or multiple components (Select group)
• Use the menu buttons or keyboard
shortcuts to Cut (ctrl+X), Copy (ctrl+C),
Duplicate (ctrl+D) and Paste (ctrl+V)
• Rotate with buttons, or with Left Click
then Right Click
• “Rubber bands” to move a component
while still connected to the circuit
• Refresh the screen with the “R” key
• Add tools: View/Toolbars Customize
Demo Moving Components
Adding to the Tool Bar
• Open click view and
Toolbar Customize
• Select the Item that you
would like to add from
the Customize dialog
• Holding the mouse left
button move the item to
the Toolbar
• To remove, open same
customize dialog and
click and move item off
the Toolbar
Before the item
was added
Add Rubber bands to Tool Bar
Configuring Default Settings
• Users can adjust the default simulation
settings that are applied whenever a
new case is created
–Tools -> Options -> View/ ATP -> Edit
Settings
–Make desired changes (such as for most of
us making 60 Hz the default)
–Click Apply and Save when finished
Show Options, Add 60 Hz
Component Defaults
• You can edit individual
components
– Double click components –
<Edit Definitions> –
<Data>
• You can edit all defaults
– <Library> <Edit object>
<Standard>
Open Component Default, Change to R=.001)
Nodes
It is very important to give every node a meaningful, recognizable
name
• Right Click on a node, then enter a name
–Up to 6 characters for 1-phase, 5 characters for 3-phase
–Use any combination of numbers and capital letters
–If no name is provided, ATP will generate a meaningless name consisting of “X” and
random numbers: X1234
• Edit -> Move Label (ctrl + L) to move node names or labels that are inside the
component icon area
• Select “Name on Screen”, “Short Circuit” or “Ground”
Name one end, short other
Single-Phase vs. Three-Phase
• ATP Draw has 1-phase and 3-phase electrical components
• 3-phase components cannot be directly connected to 1-phase
components, and vice versa
– Use “Probes & 3-phase -> splitter” to convert a 3-phase node into three 1phase nodes
– Can’t connect split phases directly; use a switch or small resistor
– 1-phase components are shown by thin lines
– 3-phase components are shown by bold lines
Connect Splitter, add resistors
Comments, Labels, and Icons
Comments
•
A comment box is provided for each ATP Draw component
– Up to 80 characters
– Comment lines (beginning with “C “) will appear in the .atp file right
before the respective data
– A comment should be added for every component
• A comment may be added for the entire case
– This comment will appear at the beginning of the .atp file
– Edit -> Comment; View -> Comment Line
Labels and Icons
• Each component can be labeled
– Up to 8 characters
– Labels appear in the ATP Draw
display, but not in the .atp file
• Each icon can be edited
– Make the ATP Draw display look
more like a real circuit
– Click the icon in the bottom left of
the component data screen to
open the Icon Editor
Show Icon Edit
Output Quantities
• The user tells ATP which output
waveforms to store in the .pl4
file
• Option 1: Insert probes (1-ph
or 3-ph) into the circuit
–Current in a branch: Probes & 3-
phase -> Probe Curr
–Voltage to ground: Probes & 3-
phase -> Probe Volt
–Voltage across elements: Probes
& 3-phase -> Probe Branch volt
• Option 2: Select an output for
each component:
Add branch current and voltage probe
Sorting Cards with ATP Draw
• Control layout of .atp file
• Important for complex cases
• Sort by Cards
– Elements will be sorted by type:
branch, switch, source, TACS
• Sort by Order
– Each ATP Draw element has a
Group Number field
– Elements with smaller numbers will
be placed first in the .atp file
– Doesn’t work for TACS (bug)
• Sort by Position (X-pos)
– Elements to the left will be first
Show group number in edit
Defining Constants
• Define constants in ATP Draw that
can be used many times
• ATP -> Settings -> Variables
• Creates a $PARAMETER card in the
.atp file
• Type the NAME in the data field of a
component to assign it the
respective VALUE
• Be sure to include a decimal
point after each value in the
settings menu
Add variable, R1=.001
Inserting ATP Draw Circuit Diagrams into a Word
Document
• Create the circuit diagram in ATP Draw
• Fence the circuit or elements to be saved
• Select File -> Save Metafile in ATP Draw
• Create or open a document with Microsoft
Word
• Select Inset -> Picture -> From File in Word
Running ATP Simulations
• Modeling principles
• Create a simple case
• Outputs and errors
Modeling Principles
• Start by building and running simple cases
• Make incremental changes
– Save the updated case with a new file name
• Verify results - Don’t just hit the I believe button!
–
–
–
–
Compare simulation results to known values
Compare models with other people
Be alert for numerical integration errors or other simulation inaccuracies
Compare simulation results to known values – Oh did we say that already!
• Once you have a good model, save it and reuse it
– Don’t start over from scratch
Always Check Circuit
• Steady State Simulations (remember -1 in Tmax)
–
–
–
–
–
–
–
Run steady state case (w/o faults)
Run L-G faults
Run 3-Phase faults
Check bus voltages
Check power flow between buses
Check for errors
Check for ‘Disconnected Sub-Networks’
• Then Run simple transient case
– Build the case up and check it periodically
Circuit Check Out – Power Flow
• Set Tmax in Setup Dialog to -1
• Run Case
• View List File ( the switch currents should match what you planned)
– The portion of the list file is ¾ the way down in the listing
Open 1-Example Power Flow
Circuit Check Out – Line-Ground Faults
•
•
•
OK lets check the L-G fault currents from each of the sources
If your transient source bypass resistors are less than 5 times the source X1 you
may want to hide them
Source contribution can be evaluated in two ways:
– Fault the bus adjacent to the source and compare to a program such as Aspen
– Isolate the source & source impedance from the rest of the network to evaluate if the
source sequence parameters are correct
•
Run the case & the list file should have the following:
Open 1-Example L-G Faults
Circuit Check Out – 3 Phase to Ground Faults
• Next is 3-Phase faults
• Hide the L-G Fault icon and unhide the 3-Phase fault icon
• Run the case & the list file should show the 3-phase faults currents
Open 1-Example 3-Phase Faults
Rule Book Useful References
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Startup File Definitions
Frequency Scan
Misc. Data Cards
Statistics Cards
R-L Line (51-52-53)
TACS Resistance
Switches
Statistic Switch
Sources
Synchronous Machines
Universal Machine
Statistic Control
Saturation
Line Constants
Cables
Cable Parameters
1E-7
2A-14
2B-1
2C-1
4C-3
5-3
6A-3
6A-13
7A-1
8-1
9G-3
15-1
19G-1
21-1
23A-1
23 Appendix
Example Circuit
• Create a 3-phase circuit with
ATP Draw
• Adjust simulation settings:
– time step = 1 us
– simulation time = .05 s (3
cycles)
– Xopt = 60 (inductance in W)
– Copt = 0 (capacitance in mF)
– Sort by Group Number
– Sort by Cards
• Place each component
– Enter data and select desired
outputs
– Edit comments, labels, and icons
– Use meaningful node names
Create a 3-phase circuit with ATP
Draw
• All of the
components in
the graphics
have been unhidden
Open 1-Example
Voltage Sources
• Power system voltages are often stated as line-to-line, rms values
• ATP voltage source amplitudes are entered as line-to-ground, peak
values
• For example a 3-phase voltage source of 10 volts (L-L, rms,
nominal) has an amplitude in ATP = 8.165 V peak
System Voltage
kV L-L rms
12.47
24.94
34.5
69
115
138
161
230
345
525
765
ATP Voltage
V L-G peak
10,691
21,382
29,578
59,155
98,592
118,310
138,029
197,184
295,776
450,094
655,851
VL -G Pk  1.05  VL - L rms 
2
3
• Most of our simulations are run with
sources in V rather than in kV
• In many cases you may want the source
to be adjusted to max. voltage, that is
the reason for a 1.05 multiplier
Show Voltage Source
Time-Controlled Switches
• Switches open at the first time
point after T-op that I <= |Imar|
– For Imar = 0: open at current zero
• Set T-cl = -1 for switch to be
closed in steady-state at T<0
– Both are initially closed in Example
• Set T-cl = .005575 for Example
– For transient cases close switches
point on wave, such as crest
voltage
• Set T-op = 100 (large number)
– Means switch stays closed for entire
simulation
– Could be opened during case to
check for breaker TRV
Show switch
Passive Circuit Elements
•
Resistors, Inductors, Capacitors, MOVs, etc.
•
Don’t try to violate the Laws of Physics
–
–
•
Current can’t change instantaneously through an inductive element
Voltage can’t change instantaneously across a capacitive element
An RLC branch with exactly zero impedance will cause a
numerical integration error:
–
–
–
I = V/Z = V / 0 = ATP crash
Accurately model components by including resistances/natural
damping (change default SCL)
Use very small impedance (R = 1e-5)
MOSA Models
• One way to model an arrester is to use the MOV Type 92 (1 or 3-phase)
• Adjust the Ref Voltage to One Block and enter number of blocks in series
(#SER) and number in parallel (#COL)
• Does not always work sometimes you’ll receive convergence error message
Show Type 92
MOSA Model Data
• Enter the data for one
block in crest voltage and
current
• Remember do not enter
0,0 as the first point, ATP
Draws does that.
• The model uses a Hans
developed routine for
establishing the segments
Alt. MOSA Model using ZNO Fitter
• First open the .atp file in notepad
• Enter your V-I characteristics and a value for A1 (The best
A1 seem to produce a multiplier near 1, more later)
Open Zno.atp
Alt. MOSA Model using ZNO Fitter
•
•
•
Now lets run your model directly in ATP to create a punch file that contains the
characteristic you will need.
If everything works correctly you should have a ZNO.pch file in the same
directory containing the ZNO.atp file
Look at the Multiplier – if near 1 comment out everything except the data in the
green box below and save the file as for example ZNO.lib
Open ZnO.pch
Alt. MOSA Model using ZNO Fitter
• Now open a new MOV Type 3-ph dialog enter a Vref at about 75% of
the desired protective level and go to the “characteristics” dialog to
enter the model
• Now “Edit”, “Import” your new model (example should be zno.lib)
• The only thing left to do is to test it and make a final Vref adjustment
Testing MOSA Models
•
•
•
•
•
All arrester models must be tested to verify that there are no errors and the desired
protective level is obtained
To test the model open Example 2 and paste your new arrester in this case
Adjust the source voltage to just above the protective level and run the case.
Now using Plotxwin, plot the voltage against the current and check the protective level
If the protective level is not correct adjust Vref in your arrester model dialog and re-run
the case, once it checks out it is ready to use elsewhere.
Open 2-MOSA.ACP, run, plot
Ideal Transformer Model
• Create an effectively ideal Y-Y
transformer or with single phase
units delta windings
– Very small (but not zero)
resistances, reactances, and
magnetizing current
– Very large magnetizing resistance
• Single phase and three phase
models are available
– Just put in the turns ratio “n”
• Floating sub-network
– Watch out in delta windings
Open 3-Transformers.acp
Saturable Transformers
• Windings can be
configured as a wye,
delta, auto or zig-zag
• Core can be 3 or 5 leg
• Be careful with Y - Delta
transformers
• Put impedance and
nonlinear saturation on
the Y-side
Transformer Test Circuit
• Primary/Secondary Voltages
– “PRI” “SEC#” nodes
– 69 kV – 12.47 kV (L-L, rms)
• Ideal, Y-Y
– “SEC1” node
• BCTran, Y-Y
– “SEC2” node
• BCTran, Y-D
– “SEC3” node
• Hybrid, Y-Y
– “SEC4” node
Transformer Waveforms
• Plots of primary and
secondary voltage
• Plots of first two
secondary currents
12
[kV]
8
100
4
• BCTran Y-Y
50
0
0
-50
-4
-100
-8
-12
• Ideal Transformer
200
[A]
150
-150
0
10
20
(f ile 3-Transf ormers.pl4; x-v ar t) v :PRI1A
30
40
[ms]
50
v :SEC1A
-200
0
10
20
(f ile 3-Transf ormers.pl4; x-v ar t) c:SEC1A -
12
[kV]
8
30
c:SEC1B -
40
[ms]
50
c:SEC1C -
200
[A]
150
100
4
50
0
0
-50
-4
-100
-8
-12
-150
0
10
20
(f ile 3-Transf ormers.pl4; x-v ar t) v :PRI1A
30
v :SEC2A
40
[ms]
50
-200
0
10
20
(f ile 3-Transf ormers.pl4; x-v ar t) c:SEC2A -
30
c:SEC2B -
40
[ms]
c:SEC2C -
Run, plot example
50
Transformer Waveforms
12
[kV]
8
• Plots of primary
and secondary
voltage
• Plots of next two
secondary currents
• BCTran D-Y
200
[A]
100
4
0
0
-4
-100
-8
-12
0
10
20
(f ile 3-Transf ormers.pl4; x-v ar t) v :PRI1A
30
40
[ms]
50
v :SEC3A
0
10
20
(f ile 3-Transf ormers.pl4; x-v ar t) c:SEC3A -
30
c:SEC3B -
40
[ms]
50
c:SEC3C -
200
[A]
150
12
[kV]
8
100
4
• Hybrid Y-Y
-200
50
0
0
-50
-4
-100
-8
-12
-150
-200
0
10
20
(f ile 3-Transf ormers.pl4; x-v ar t) v :PRI1A
• All four secondary
voltages and
currents
30
40
[ms]
50
v :SEC4A
0
2000
[V]
1500
200
[A]
150
1000
100
500
50
0
0
-500
-50
-1000
-100
-1500
-150
-2000
0
10
20
(f ile 3-Transf ormers.pl4; x-v ar t) v :SEC1A
v :SEC4A
30
v :SEC2A
40
[ms]
v :SEC3A
50
10
20
(f ile 3-Transf ormers.pl4; x-v ar t) c:SEC4A -
-200
0
10
20
(f ile 3-Transf ormers.pl4; x-v ar t) c:SEC1A c:SEC4A -
30
c:SEC4B -
30
c:SEC2A -
40
[ms]
50
c:SEC4C -
40
[ms]
c:SEC3A -
50
Transmission Line Models
• Lumped p model
– Inadequate for electromagnetic transient analysis
• Constant distributed parameter models
– R, L, and C do not vary with frequency
– Clarke and KC Lee lines in ATP
• Inputs: sequence components or Line Constants
• Frequency dependent distributed parameter model
– Characteristics of zero sequence, or ‘ground mode’ of a line
change significantly with frequency
• Increase in resistance, decrease in inductance with frequency
– JMarti line in ATP
• Inputs: Line Constants – physical properties of the conductors
(size, dc resistance, spacing between phases, transposition,
overhead ground wires)
Clarke Line Model
• Iline controls input format
of A, B
– Iline = 0: positive and zero
sequence L, C per unit
length
– Iline = 1: surge impedance
and propagation velocity
– Iline = 2: surge impedance
and travel time
• Line Parameter Data
• l = length of line (miles or
km)
Open 1-Example then Clark.xls
Line Constants Input
Generate .atp card using ATP Draw or ATP LCC,
Save As and Run ATP
• Different LCC models
– Lumped Pi
– Constant distributed parameter (Bergeron)
•When TRANSPOSED is selected model is CLARKE
•When UNTRANSPOSED is selected model is KCLEE
– Frequency dependent (JMarti, Noda, Semlyen)
• Segmented Ground (overhead ground wires)
– Use this option for 500 kV lines, but not for lower voltages
Back to 1-Example
Line Constants Data
Click on Data
Model data is entered here
Click on View
Shows the graphical
representation of what
you entered
Open Conductor.xls, JMarti.xls
Line Parameter Checking
Click on Verify: Performs freq scan or provides power freq impedances
Line Constant Input - JMarti
Best model for most transient studies
Unless you are performing
Steady state studies ALWAYS have
“Real Transf. Matrix” checked
•
Unselect “Transposed” if
you plan on entering specific
transpositions between line
Segments
•
Unselect “Segmented
Ground” where the OHGW is
Continuously bonded to each
Structure
•
Increase “Freq Matrix”
To 5000 or above if you are
Performing lightning studies
•
Remember to view
and verify your model
Back to 1-Example, open Jmarti
TACS
•
•
•
•
Overview
Input and Output
Components
Example: A/D conversion
Overview of TACS
• Transient Analysis of Control Systems
– Transfer functions, devices, logical and mathematical operators
• TACS gets voltage, current and/or switch status inputs from the electrical
network
• TACS sends voltage or current source magnitude, switch open or close signals
or variable resistance values to network
• A one-timestep delay is involved in TACS – Network interactions
• TACS has been used for HVDC, SVCs, breaker prestrike, continuous analysis of
network quantities and much more.
• TACS can be run in “Hybrid” mode with the electrical network or in a “Stand
Alone” mode using only TACS components.
• TACS can be used as a convenient method of performing mathematical
analysis on network signals
TACS Input
• TACS components and nodes cannot be connected
directly to electrical components and nodes
• Use the “TACS -> Circuit Variable” input probe to obtain
a TACS signal from an electrical network signal
– Voltage Input = Type 90
– Current Input = Type 91
– Connect to the input of a switch to probe the current through
the switch
Open TACS Couple
TACS Input
• Use the same name for electrical and TACS input nodes
– If working with a 3-phase electrical network, add the phase letter
to the TACS node name because inputs to TACS components
are 1-phase
• TACS node types
–
–
–
–
0=Output
1=Input signal positive sum up
2=Input signal negative sum up
3=Input signal disconnected
Open TACS Component
TACS Output
• “Probes & 3-phase -> Probe Tacs” sends outputs from the
TACS network to the .pl4 file
– Similar to the voltage and current probes used in the electrical
network
• TACS-controlled switches, sources, and resistors
– Electrical components used to implement feedback control
– Give the control node the same name as the TACS network output
node
– These components are 1-phase only, so a splitter may be needed
when working with 3-phase networks
Show TACS output probe
Running the Case
• When all desired components have
been placed, save the .acp file
• Run ATP
• After case is run the following files
may be opened
–.atp file (F4 or mouse click)
–.lis file (F5 or mouse click)
–.pl4 file (mouse click PlotXY or ATP
Analyzer)
Note:Newer versions of ATP now use “.acp” for file extensions due to
conflicts with Microsoft file extension “.adp”. Either “.acp” or the
older ATP file extension “.adp” will run in newer version of ATP.
Run 1-Example
Input and Output Files
•
Three files are generated by ATP if the case runs
successfully:
1) .atp file – ‘Card-mode’ file for ATP execution
2) .lis file – Card interpretation by ATP, model connectivity, steadystate phasor solution, listing of transient solution with switching
times and min/max values, and error messages.
3) .pl4 file – Output file for plotting waveforms
•
ATP Draw stores .acp, .pl4, and .lis files in this default
directory: (or the directory that you selected)
–
•
C:\ATPDraw\Atp
All of these files have the same name as the respective
ATP Draw file (.acp)
Show output
Open .atp File
Open .lis File
File provides steady state currents and
voltages, nodes, phasor solutions and
program trouble shooting data
File shows exactly what was passed from
ATP Draw to the ATP Program
Steady State Phasor Solution
• .lis file contains the steady state phasor solution
– Switch currents
– Node voltages
– Power flows
• Polar and rectangular form
• Network connections
• View .lis file from ATP Draw to verify simulation results
– ATP -> edit LIS-file (F5)
– Review slides 36-38
Open .lis file
Output Traces
• .pl4 file contains requested output traces
– x-axis: time or frequency
– y-axis: voltage, current, power, or energy
• View with PlotXY, PLOTXWIN or ATP Analyzer
– PlotXY and PLOTXWIN are fast and easy to use
– ATP Analyzer has more advanced capabilities, including
mathematical analysis functions
• Be consistent with input and output units:
– Voltage source in V -> outputs in V, A, W, var
– Voltage source in kV -> outputs in kV, kA, MW, Mvar
Open .pl4 w/PlotXwin
List Size Overflow Error
• ATP allocates a certain amount of storage space in memory for
storing data
– listsize.dat
• If these limits are exceeded, the case will not run
– Example: A very small time step in a case with long transmission lines
can produce an ATP error
• You could:
– Copying the newer version of listsize.dat (7/28/1998) from the class CD
into the directory where ATP is installed might solve some of these
problems
• Same directory as TPBIGW.exe
– If not, try modifying the case until you can get it to run
– Use GIGMINGW.zip version
– Complile your own version is sometimes an option
ATP Errors
• ATP formatting rules are extremely unforgiving
– Exactly 80 characters per line
• What if the case is not formatted properly or something else is wrong?
– ATP may also just quit with no message
– ATP will usually generate an error message in the .lis file
– These messages can be cryptic and condescending:
• “You lose, fella.”
• “Such degenerate usage of the computer will not be allowed.”
• “This is objectionably stupid”
– No output traces in the .pl4 file
• What if the input data is properly formatted but not accurate?
– ATP will still run the case and produce outputs
– Garbage in -> garbage out
– Start with a small and verifiable case and add to in small increments
– It is important that you test and verify your results as you build a
case
Other ATP Issues
•
•
•
•
•
•
•
Never try to run a case where either the folder of the file name has a space in the name
(It will always fail and you will not know why, see example where file was named
–
1-ExampleCkt-Name with space.acp
Special characters such as /@#%$^& are not allowed (So far – and _ are known to be
allowed)
Do not mix upper and lower case as we have found out that TACS will sometimes produce
errors
When creating your own libraries and a “Blank Card” is called for to end the $Include,
Type “BLANK CARD” into the last card
Also if the sum of the folder and files names exceed 80 characters the case will fail
When numerical oscillations occur insert the appropriate resistances in the nearby
components
The new BCTRAN and HYBRID transformer models have special rules, follow them
Run 1-Example Name w/
Plotting Programs
• Multiple programs exist for plotting output signals from ATP cases
• Input format: .pl4, Comtrade, or Text Table
• ATP Analyzer
–
–
–
–
Perform mathematical analysis functions
Compare waveforms from different cases
Overlay charts or separate charts
View and generate Comtrade or Text Table files
• PlotXY or PlotXwin
– Fast and easy to use
– Multiple plot windows
– Lacks advanced mathematical analysis capabilities
Using PlotXY or PLOTXWIN
• Open with shortcut in ATP Draw (see slide ??)
• Plot up to 8 output traces simultaneously on single axis
– Zoom in: Left click and draw a box
– Zoom out: Right click
– Compare traces from different cases
• Buttons
– Grid, Cursor, Manual Scale, Title, Mark, Copy, Print
• Additional features in the newest revision
– Display the Fourier components of 1 signal using a DFT algorithm
– Add, subtract, or multiply 2 signals
Open 1-Example, PlotXwin
PlotXY Example: RLC Circuit
• Select desired signals from the
menu, then Plot
– Shown is the voltage at different
points along the line
– Notice the high line end voltage
PLOTXWIN Example
Line end voltage w/o MOSA
Window for selecting plotted quantity
Line end voltage w/ MOSA
Modify circuit to show, voltage and energy
Using ATP Analyzer
• Open a new .pl4 file
–File -> New -> Atp.pl4
Import
–Look in C:\ATPDraw\Atp
• Analyzer cases can be
saved as .mdb files
• Startup file NEWPL4 may
have to be changed if 2
was previously selected, 1
works for both but units
are not always correct
ATP Analyzer Traces
• Select desired traces for
plotting by clicking on them
• Selection commands
– Edit Selections
– Select All
– Clear Selections
• Use the Charts menu to
create plot of desired traces
Update Startup, Run Case, Plot Output
Analyzer: Multiple Overlay Chart
• Change title of case and
add up to 5 lines of
comments
• Zoom
– Time -> Zoom
– In: Left Click and draw a
box
– Out: Right Click
• Change the x-axis scale to
seconds, milliseconds, or
cycles
– Time -> Scale
Plot multiple then overlay
Inserting Traces into a Document
• Save overlay charts
– Copy chart to clipboard
– Copy chart to file
• Save multiple charts
– Print->Save File as .wmf
– Must have a printer attached
• Save multiple chart individual
signals
– Options -> Copy Chart -> To File
• Open Microsoft Word or
PowerPoint
– Insert -> Picture -> From File
– Select desired .wmf file
Analyzer: Overlay Chart
• Good for comparison of two
quantities
• Options similar to “Multiple
Charts”
• Use Charts to switch back
and forth between Multiple
and Overlay
• Click Done to return to the
signal selection screen
Plotxwin overlay example
1.2
[MV]
0.9
0.6
0.3
0.0
-0.3
-0.6
5
6
7
(f ile 1-ExampleCkt.pl4; x-v ar t) v :L1B
v :L5B
8
v :L2B
9
v :L3B
10 [ms] 11
v :L4B
Analysis Functions
• Perform mathematical analysis on desired signals from the main case
–Analyze menu
–Mathematical, Modify Signal, Evaluate Signal
• Outputs of the analysis functions are stored as new signals
–Analysis functions can be performed on analysis signals
–Analysis signals can be plotted with electrical signals from the case
Show Features
Analysis: Mathematical
• Perform arithmetic operations on two signals
–Add, subtract, multiply, divide
• Covert complex numbers between polar and rectangular form
• Logarithms
Add signals and plot
Analysis: Modify Signal
• Differentiate and integrate
• Multiply by a constant
• Filter, clip, offset, and rectify
Analysis: Evaluate Signal
• Transformations of 3-phase voltages and currents:
– Symmetrical components (+, -, 0)
– Park (d, q, 0)
– Clarke (a, b, 0)
• Power, impedance, and harmonics calculations
• RMS
Comtrade Files
•
IEEE Std. C37-111
–
•
Sources of Comtrade files
–
–
–
–
–
•
Common Format for Transient Data Exchange
Digital fault recorders (DFR)
Analog tape recorders
Digital protective relays
Transient simulation programs (ATP/EMTP)
Analog simulators
Best Comtrade format 1999 Binary
Open Comtrade with ATP Draw
ATP Multi-Overlay Analyzer Example
First Open a Plot File
Then go to <Charts> <Multiple
Overlay Charts>
Add desired signals to each
chart in order
Then back to <Charts>
<Multiple Overlay Charts>
Compliments of the Bonneville Power Administration
Models Programming Language
• Features
• Creating a Model
• Predefined Functions
• Model Examples
MODELS
• MODELS is a programming language for creating new ATP
components
– A model is a black box that performs control or mathematical
analysis functions
– Similar to TACS, but with a more object-oriented structure and more
advanced capabilities
– TACS components can be constructed in MODELS
• The MODELS in ATP Language Manual is included on the
class CD
– Detailed description of the syntax
– Many examples of models and functions
Features of MODELS
• From MODELS in ATP Language Manual:
– Each model uses a free-format, keyword-driven syntax of local
context, and does not require fixed formatting in its representation
– A distinction between the description of a model and its use allows
for multiple independent replications of a model with individual
simulation management (time step, dimensions, initial conditions)
– A system can be described in MODELS as an arrangement of interrelated submodels, independent from one another in their internal
description
– A model’s description can also be used as its documentation
– The models and functions used for describing the operation of a
system can be constructed in programming languages other than the
MODELS language
Creating a Model
•Create a .mod file and a .sup file for
every model
–Both are stored in the C:\ATPDraw\Mod
directory
–Up to 8 characters, with no spaces in the
name
–The .mod file is a text file that is
formatted according to the rules of the
MODELS language
–The .sup file is an ATP Draw file similar
to .sup files for electrical and TACS
components
Structure of the .mod File
• Part 1: Declaration
– Begins with MODEL and the name of the main model
– Inputs, outputs, data, global constants, variables, submodels, userdefined functions, memory allocation (delay), and history signals
– Performed once, at the start of the ATP simulation
• Part 2: Initialization
– Begins with INIT, ends with ENDINIT
– Set initial values of variables and outputs once, at the start of the
ATP simulation
• Part 3: Execution
– Begins with EXEC, ends with ENDEXEC
– Calculations and assignments performed at every simulation time
step
– Use pre-compiled functions and/or user-defined functions
Pre-Defined MODELS Functions
•The assignment operator is ‘:=’
•Algorithm control
–if, else, elsif, endif
–for, while, do, error, combine
•Logical
–or, and, not, nand, nor, xor, bool
•Comparison
–>, >=, <, <=, =, <> (not equal)
•Arithmetic
–+, -, *, /, mod, ** (exponent)
•Numerical
–abs, sqrt, exp, ln, log10, log2,
recip, trunc, factorial, round,
random, sign, rad, deg, max, min,
norm
•Trig
–sin, cos, tan, asin, acos, atan,
atan2, sinh, cosh, tanh, asinh,
acosh, atanh
•Arrays
–a[1..3] = [1, 2, 3]
•Differential equations and transfer
functions
–diffeq, laplace, zfun
•Derivatives and integrals
–deriv, deriv2, integral
•Simulation
–delay, predval, predtime, backval,
backtime, histval, histdef
MODELS .sup File
•Data
–Parameters that can be varied by the ATP Draw user for each instance of the model
–Set the default values
•Nodes
–Kind (see next slide)
–Position (1-12)
–Number of phases (1 or 3)
•Edit the icon
•Add a help file
–Describe the function of the model
–Define the inputs, outputs, and data
MODELS Nodes
• Electrical and TACS nodes can be directly connected to the input of a
MODELS component
• Each MODELS node must be the correct kind
–
–
–
–
–
–
–
–
–
0
1
2
3
4
5
6
7
8
=
=
=
=
=
=
=
=
=
Output.
Input current
Input voltage
Input switch status
Input machine variable
TACS variable
Imaginary part of steady-state node voltage
Imaginary part of steady-state switch current
Output from other model.
MODELS Example
• Sequence network transformation
– Convert time-domain 3-phase voltage or current signals into zero,
positive, and negative sequence (0,1,2) signals
– Use the simple electrical network from the TACS example (1 V
source, 1 W resistor)
– SEQ_V.mod for voltages: input nodes are type 2, single-phase
– SEQ_I.mod for currents: input nodes are type 1, single-phase
Other Types of Simulations
• Frequency scan
• Harmonic frequency scan
• Statistic and systematic switches
Frequency Domain Simulation Settings
•ATP -> Settings, or F3
•Frequency Scan
–min = starting frequency
–max = ending frequency
–df = frequency increment
–NPD = points per decade,
logarithmic scale
–NPD = 0 -> linear scale
•Harmonic Frequency Scan
–Select Power Frequency
–Input system frequency (Freq
= 50 or 60)
9) Frequency Scan
• Use only one source in the circuit
– Voltage excitation or current injection
– Set the source amplitude to 1 (per unit)
– Ground all other sources
• View frequency scan output traces with ATP Analyzer
– Do not use PlotXY (discussed later)
• Input: voltage excitation of 1 per unit
– Output: per unit voltages and currents vs. frequency
• Input: current injection of 1 per unit
– Output: per unit equivalent impedances vs. frequency
• Convert per unit values from ATP to physical units
Frequency Scans
• Prior to performing a frequency scan setup your circuit as
follows:
– Hide all system voltage sources
– Ground the node that the voltage source was connected to
– Connect a 1A current source to the bus being evaluated
• Here is an example circuit
Frequency Scans
•
Open the ATP settings dialog and
– Set Simulation to Frequency Scan
– Set Frequency Scan min, max and df to cover the range of frequencies being
evaluated and the frequency steps
– Click on the desired output
•
Open your Startup file if NEWPL4 was previously set to 1
– Set it to 2 for PlotXwin plots
– Set it to 0 for ATP Analyzer plots
•
•
•
Now run the case
Among the variables available you should see these: (using PlotXwin)
Having selected in the Output
dialog the magnitude, angle,
real, imaginary you should
see the following four
quantities available for
plotting
Frequency Scan Output
Magnitude
Real
Angle
Imaginary
Harmonic Frequency Scan
• Output voltages and currents
resulting from harmonic distortion
• Set Power Frequency = 60 in ATP ->
Settings -> Simulation
• Use the HFS source
– Single phase only
• View harmonic frequency scan output
traces with ATP Analyzer
– Do not use PlotXY
Statistic and Systematic Switches
• Statistic switch
– random opening / closing times
• Systematic switch
– Incremental opening / closing times
• ATP -> Settings -> Switch/UM
• NUM = number of ATP simulations
• Probability distribution
– Gaussian if IDIST = 0
– Uniform if IDIST = 1
Statistic Switches
• Right click -> Switches ->
Statistic Switch
• T = average opening time
• Dev = standard deviation
• Switch only opens/closes when
current is less than Ie
– Similar to Imar for time –
controlled switches
• 1-Phase components only
– For 3-phase, use a splitter and
three statistic switches
Systematic Switches
•Right click -> Switches ->
Statistic Switch
•Not random
–Tbeg = beginning time
–INCT = time increment
–NSTEP = number of
increments
•Master / Slave
–Opening time of slaves is
delayed from master
–Use a systemic switch for the
master
–Use three statistic switches as
slaves
Using ATP for Relay Testing
1) Create and run a case with ATP Draw to generate a .pl4 file
2) Open the .pl4 file with ATP Analyzer
3) Save desired voltage and current signals as Comtrade files (binary or
ASCII format)
4) Open the Comtrade file with the test equipment software (Doble F6150,
ProTest or TransWin programs)
5) Play the voltage and current signals into the relay