The Power System Analysis Toolbox (PSAT) is a Matlab toolbox for electric power system analysis and simulation. The command line version of PSAT is also GNU Octave compatible. All operations can be assessed by means of graphical user interfaces (GUIs) and a Simulink-based library provides an user-friendly tool for network design.

PSAT is ditributed under the General Public License (GPL) and comes with no warranty conditions. The latest PSAT version can be downloaded here.

The main features of PSAT are: Power Flow; Continuation Power Flow; Optimal Power Flow; Small Signal Stability Analysis; Time Domain Simulation; Complete Graphical User Interface; User Defined Models; FACTS Models; Wind Turbine Models; Conversion of Data Files from several Formats; Export results to EPS, plain text, MS Excel and LaTeX files; Interfaces to GAMS and UWPFLOW Programs; Command Line Usage; and GNU Octave Compatibility.

Abrief introduction to PSAT is available here. This presentation was given at the first IEEE panel session on Open Source Software at the PES Meeting of Montreal, Canada, on June 20, 2006. A didactical tutorial to PSAT is available here.

Letters of reference for PSAT are available here. If your University, Institution or Company is using PSAT, please send me a letter of reference. These letters are important for me in order to request funds to my University and, in turn, to keep developing PSAT.

The PSAT documentation is no longer provided for free. Please contact me for getting the details on how to obtain the full PSAT manual as well as any other assistance on PSAT. I am also available for defining as hoc appointments for developing specific features currently not implemented in PSAT.


PSAT Version Matlab GNU Octave
Last update: April 4, 2022.

Please read the "no warranty" conditions below.

No Warranty

Because the software package "PSAT" (hereinafter "the toolbox") is licensed free of charge, there is no warranty for the toolbox, to the extent permitted by applicable law. Except when otherwise stated in writing the copyright holders and/or other parties provide the toolbox "as is" without warranty of any kind, either expressed or implied, including, but not limited to, the implied warranties of merchandability and fitness for a particular purpose. The entire risk as to the quality and performance of the toolbox is with you. Should the toolbox prove defective, you assume the cost of all necessary servicing, repair or correction.

In no event unless required by applicable law or agreed to in writing will any copyright holder, or any other party who may modify and/or redistribute the toolbox as permitted above, be liable to you for damages, including any general, special, incidental or consequential damages arising out of the use or inability to use the toolbox (including but not limited to loss of data or data being rendered inaccurate or losses sustained by you or third parties or a failure of the toolbox to operate with any other software), even if such holder or other party has been advised of the possibility of such damages.


Countries where PSAT is used are indicated in red in the map below. If you are using PSAT and your country is not in red, please let me know!.



  • April 4, 2022: Yet some more bug fixes by Andreas Wank.
  • March 2, 2022: Some bug fixes by Andreas Wank.
  • August 17, 2019: Support up to Matlab R2019a (beta). Simulink model warnings fixed by Behnam Tamimi.
  • June 7, 2016: Support for Matlab R2016a (beta). Several GUIs' bugs have been fixed by Hantao Cui.
  • May 26, 2016: PSAT version 2.1.10. Compatible with Matlab R2014b, R2015a and R2015b. Some bugs have been fixed.
  • September 6, 2014: PSAT version 2.1.9. PSAT Documentation available for purchase. Compatible with Matlab R2014a and syntax consolidation. Fixed a few bugs.
  • January 6, 2013: PSAT version 2.1.8. Added 2 compact solar photo-voltaic generator models (thanks to B. Tamimi and C. Cañizares). Fixed a few bugs.
  • July 30, 2012: PSAT version 2.1.7. Compatible with Matlab 7.14 (R2012a). Added 4 hydro turbine models (thanks to W. Li and L. Vanfretti). Fixed the exponential recovery load model and several other bugs.
  • May 13, 2010: PSAT version 2.1.6. Yet another minor release. Compatible with Matlab 7.10 (R2010a).
  • November 1, 2009: PSAT version 2.1.5. Yet another minor release.
  • June 17, 2009: PSAT version 2.1.4. Minor release that fixes a few bugs.
  • April 21, 2009: PSAT version 2.1.3. Minor release that consolidates device classes and fixes several bugs.
  • June 26, 2008: PSAT version 2.1.2. Minor release that fixes some bugs in the CPF analysis.
  • June 18, 2008: PSAT version 2.1.1. Minor release that fixes a bug in the AVR class.
  • June 16, 2008: PSAT version 2.1.0. PSAT can run on any Matlab version back to 5.3 and on GNU Octave. The GUI for 3D visualization for static and dynamic power system analyses has been completed. The library for Numerical Linear Analysis has been completely rewritten and split into a Linear Analysis library and a Numerical Differentiation library. A filter for the ODM (open data model) has been included. The GUIs have been optimized for running on Quartz (Mac OS X) and X11 (Linux) graphical systems.
  • February 2, 2008: PSAT version 2.0.0. The whole PSAT code has been rethinked and rewritten using classes and object oriented programming techniques. Each device is defined by a class with attributes and methods. The algorithms of PF, CPF, OPF, SSSA and TD have been rewritten, improved and made more robust. The Simulink library has been renewed using "physical" components. This avoids the directionality of control blocks and allows producing high quality network schemes. Added the status field to most components. A component can be put on-line or off-line by toggling its status. New more reliable versions of TCSC, SSSC and UPFC devices and Power Oscillations damper model has been provided by H. Ayres, M. S. Castro and A. Del Rosso. The HVDC model has also been rewritten. Several new filters for data format conversion have been added. Most filters has been provided by J. C. Morataya. PSAT has been tested with very large static and dynamic networks (up to 15000 buses). The logo of PSAT has been changed.
  • November 20, 2007: PSAT version 2.0.0 beta 4. Fully class-based version. 3D visualization of power systems. Several components and models have been completely revised and rewritten. This is an almost stable version and is only compatible with Matlab 7.0 or newer (no GNU/Octave compatibility).
  • March 8, 2007: PSAT version 2.0.0 beta 3 . This is still a development version and is only compatible with Matlab 7.0 or newer (at the moment this version is NOT compatible with Octave). Further class development. Several improvements.
  • December 14, 2006: PSAT version 2.0.0 beta 2. This is a development version and is only compatible with Matlab 7.0 or newer (at the moment this version is NOT compatible with Octave). Further class development. Introduced the connection status for several comments. Several improvements.
  • March 24, 2006: PSAT version 2.0.0 beta 1. This is a development version and is only compatible with Matlab 7.0 or newer (at the moment this version is NOT compatible with Octave). First version of PSAT which uses classes. New more reliable FACTS models and new Power Oscillation Damper model for FACTS devices (by H. Ayres, M. S. Castro and A. Del Rosso). New Simulink library with physical components. New filters for data format conversion (by J. C. Morataya). Improved PF, CPF, OPF, SSSA and TD algorithms. Tested on a 15000 bus network.
  • July 14, 2005: PSAT version 1.3.4. Added multiperiod market clearing model for the PSAT-GAMS interface and many other improvements.
  • January 26, 2005: PSAT version 1.3.3. Minor release with a few bug-fixes and a revised documentation.
  • October 8, 2004: PSAT version 1.3.2. First version tested on Matlab 7 (R14). New Physical Model Component (PMC) Simulink Library. Several bug fixes and improvements.
  • August 2, 2004: PSAT version 1.3.1. Numeric Linear Analysis library by Alberto del Rosso. New model for direct drive synchronous generator wind turbine. PSS/E 29 filter. Several bug fixes and improvements.
  • May 2, 2004: PSAT version 1.3.0. Added a command line version and basic compatibility with GNU/Octave. New wind turbine models and bus frequency measurement. Several bug fixes and improvements.
  • November 25, 2003: PSAT version 1.2.2. Several bug fixes and improvements. Added utilities to convert data files into BPA format and to export PF results to MS Excel sheets and to LaTeX tables.
  • September 11, 2003: PSAT version 1.2.1. Includes previous patch and several other bug fixes.
  • August 31, 2003: PSAT version 1.2.0. Matlab version independent. Several bugs and typos were removed thanks to Liulin.
  • August 16, 2003: Created the PSAT Forum (available at
  • August 1, 2003: PSAT version 1.1.0. Many addings (GAMS and UWPFLOW interfaces, phase shifting transformer, etc.), improvements and bugs fixing.
  • November 11, 2002: PSAT version 1.0.0.