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Title of the script: Demonstration of a model in OpenIPSL

Keywords: SMIB, single machine infinite bus, openmodelica, omedit, openipsl, power systems, spoken tutorial, video tutorial

Visual Cue Narration
Slide Number 1Title Slide Welcome to this Spoken Tutorial on Demonstration of a model in OpenIPSL.
Slide Number 2

Learning Objectives

In this tutorial, we will learn:
  • About SMIB
  • Set up the initial values and power flow data
  • Compile a model
  • Simulation and its setup and
  • Interpreting the results obtained
Slide Number 3

System Requirements

To record this tutorial, I am using
  • OpenModelica version 1.12.0 and
  • Ubuntu Linux OS 16.04

Also, use latest version of OpenIPSL to avoid compatibility issues

I am using OpenIPSL version 1.5.0

The process demonstrated in this tutorial is identical in other OS also such as-

  • Windows
  • Mac OS X or
Slide Number 4


To follow this tutorial, you should have knowledge of :
  • Power systems and
  • Modelling using OpenModelica

For prerequisite OpenModelica tutorials, please visit this website.

Slide Number 5

What is SMIB?

First, let’s see what is SMIB.
  • SMIB stands for Single Machine Infinite Bus.
  • In this network, there is only a single machine and an infinite bus (as the name suggests).
  • The synchronous machine is connected to the Infinite bus using power lines.

Show the folder on your Desktop.

Download the files given in Code Files link of this tutorial.

And extract them into a separate folder.

Now, let us open the SMIB model in OpenModelica.

Cursor to OMEdit window. Open OMEdit window.

I have already opened OpenModelica on my system.

First, we have to include the OpenIPSL library.
File >> System Libraries >> OpenIPSL To do this, go to File >> System Libraries >> OpenIPSL.

Let me resize the libraries browser window for better view.

Point to Libraries Browser. The OpenIPSL package opens in the Libraries Browser.
Now let us open the SMIB model.
File >> Open Model/Library File. Go to File menu and click on Open Model/Library File.
Select Desktop Select the folder where the model is saved.
Click on file. Double-click on file.
Cursor to Libraries Browser. SMIB_model opens in Libraries Browser.
Double click on SMIB_model file Now double-click on SMIB_model file.

Let me close the libraries browser and messages browser for better view.

Point to Diagram View The file opens in the Diagram View.

Let me zoom in for better view.

For this I am pressing ‘Ctrl’ and ‘+’ sign simultaneously.

Point to all the components in the model.

Here we can see that, this model consists of the following components:

  • A generator of order 6 (with no controls(Constant Efd))
  • Three Buses
  • Two winding Transformer
  • Two power lines
  • An infinite bus
  • Three phase balanced fault block
Cursor to the generator and Bus 1 The generator is connected to Bus 1.

This generator has no controls but the field voltage (Efd) is maintained constant manually.

Cursor to Bus 1 and Bus 2 Bus 1 and Bus 2 are connected through a transformer.
Cursor to Bus 2 and Bus 3 Bus 2 and Bus 3 are connected through two parallel power lines.
Cursor to Bus 3 and Infinite bus. Bus 3 is connected to the infinite bus.
Cursor to Three phase balanced fault block Three phase balanced fault block is connected to Bus 2.

So here Bus2 is the fault bus.

I am scrolling up.

Cursor pointing on the System Data block The System Data block is used to set the System base and Frequency.
Point to System Data block values In this case, we can see that the system base is set at 100 MVA and frequency at 50 Hz.

I am zooming out.

For this, I am pressing ‘Ctrl’ and ‘-’ sign simultaneously.

Double click on the components to open parameter window. Before compiling the model, parameters and power flow data are required for all the components.

Double click on the generator model to open the parametric window.

These power flow data are the initial start values.

These can be obtained from PSAT or PSS/E which are the simulation tools.

/* Simulating a Class */

Here I have already entered the required data.

Let us now try to simulate the model.

I am closing this parameter window.

Now we will check the correctness of the model.
Click on Check all Models button. Click on Check All Models button which is in the top toolbar.
Point to the Messages Browser window In the messages browser, if we scroll up we can see, there are 99 equations in the model and 99 variables.

From this, we can say this model is solvable.

Close the Messages Browser Close the Messages Browser at the bottom.
Let us proceed to the simulation.
Click on the Simulation Setup. Click on the Simulation Setup option in the toolbar.
Point to Simulation Setup-SMIB_model window Simulation Setup-SMIB_model window opens.

Here we set up the solver and other parameters for the simulation.

Stop Time >> 20 Under Simulation Interval, change Stop Time to 20 secs.
Point to dassl and tolerance value. Here, we are using Dassl integration algorithm with tolerance of e-06.
Point to Simulate checkbox Ensure that Simulate checkbox is checked.
Click on Ok at the bottom. And then click on the Ok button at the bottom.
/* Switching to Simulation Output Window */ During the execution of the simulation, a new window opens.
hover the mouse on the simulation output window. It shows the compilation process of the class.
Point to the success message. After the simulation is successful executed, close the Simulation Output window.
/* Switching to Plotting Perspective */ By default, Plotting Perspective opens in the OMEdit window.
Switch to Variables Browser. At the right of Plotting Perspective, look at the Variables Browser window.
Expand the model and each component in Variables Browser We can see all the variables by clicking on the Expand button of the particular component.
Now let’s see the voltage profile at the fault bus i.e. at Bus 2.
Show the Variables Browser Expand the SMIB_model, if it is not already open in the Variables Browser.
Click on B2. Click on the right arrow button of B2 (Bus 2).

We can see all the parameters of the bus.

Click on V checkbox.

Now click on the V checkbox which is at the left-hand side of the voltage parameter (V).
Cursor on voltage profile of Bus 2. This plots the graph of Voltage at Bus 2.

Let me close the messages browser for better view.

The Y-axis unit is in per unit and the X-axis unit is seconds.

Point to X-axis. Here we can see the plot starts from 0 seconds and ends at 20 secs.
Zoom in the time plot

Cursor on the plot.

During the fault i.e. from the duration 0.5 to 0.57 secs, there is a huge dip in the voltage profile.

The fault is cleared at 0.57 secs.

Then the voltage doesn't rise quickly to its steady state value but oscillates about it.

Point to the Voltage value at t=12.5 secs. The voltage settles down after about 12.5 secs.

This time can be reduced by adding additional controls to the generator.

Cursor on the voltage profile plot We can also see that the voltage doesn't drop down to zero at this Bus, though it is the fault bus.

This is because of the fault impedance involved.

Expand B2 and B3 buses We can also view the voltage profiles of the other bus i.e. B1.

For this expand B1 in variables browser.

Now click on the checkbox of ‘v’ parameter.

After selecting B1 and B2 voltages, we can clearly see the voltage drop between the buses.

Clear the plot Now clear these plots by unchecking the parameter checkboxes.
Show the plot of Delta curve of generator It is also possible to plot the Delta curve of the generator.

This indicates whether the system is accelerating or stable.

I am scrolling down.

Expand order61 For this, expand order61 which is a sixth order generator.

Here we can see all the variables of the generator.

Click on the delta checkbox Click on the checkbox of delta to plot its graph.
Point to the plot window From the graph, we can see the system is accelerated when the fault occurs at 0.5 secs.

The delta then oscillates about the steady-state value after the fault is being cleared.

It settles down after some time making the system stable.

Slide Number 6


Let us now summarize.

In this tutorial, we have learnt:

  • About SMIB
  • Setup initial values and power flow data
  • Compile a model
  • Simulation and its setup
  • And interpreting the results obtained
Slide Number 7


As an assignment:

We recommend that you open different examples under the library.

And then simulate and explore the results.

Slide Number 8

Power System Simulation Project

The FOSSEE team invites contributions to develop power system networks using OpenIPSL library.

We give honorarium and certificates to those who do this.

For more details, please visit this site.

Slide Number 9

About the Spoken Tutorial Project

Watch the video available at the following link.

It summarizes the Spoken Tutorial project.

Slide Number 10

Spoken Tutorial Workshops

The Spoken Tutorial Project Team conducts workshops and gives certificates.

For more details, please write to us.

Slide Number 11

Forum slide

Do you have questions in this Spoken Tutorial?

Please visit this site.

Choose the minute and second where you have the question.

Explain your question briefly.

Someone from the FOSSEE team will answer them.

Slide Number 12

Forum for specific questions:

  • Do you have any general/technical questions on OpenModelica?
  • Please visit the FOSSEE forum and post your question

Slide Number 13

Textbook Companion Project

The FOSSEE team coordinates coding of solved examples of popular books.

We give honorarium and certificates to those who do this.

For more details, please visit this site.

Slide Number 14

Lab Migration Project

The FOSSEE team helps migrate commercial simulator labs to OpenModelica.

We give honorarium and certificates to those who do this.

For more details, please visit this site.

Slide Number 15


Spoken Tutorial and FOSSEE projects are funded by NMEICT, MHRD, Government of India.
Slide Number 16


This tutorial is created by Samboju Sai Kiran.

Thank you for joining.

Contributors and Content Editors

Nancyvarkey, Saikiran