1. Power System Assistant (PSA) 4.0 PRESENTATION November 2011 www.powersystemassistant.com psa@powersystemassistant.com

2. About Power System Assistant (PSA) Power Flow Calculation Base case load flow calculation N-1 and N-X contingency analyses NTC calculation Calculation of PTDFs and OTDFs Network Reduction-function based on power flow calculation Short Circuits Calculation Three phase Single phase to ground Two phase Two phase to ground

3. Improvements of PSA 4.0 comparing to PSA 3.X LU factorization of Jakobian matrix is almost three times faster; Interface function Copy/Paste for data exchanging with MS Excel i Word tables; Export/Import function CIM XML RDF format; Three-winding transformer model; Turn off/on line on the one side; Short circuit calculation function; “backward looking” algorithm for generator reactive power limits control.

4. PSA 4.0

5. Copy/Paste interface for data exchanging with MS Excel i Word tables

6. CIM XML RDF and UCTE formats export/import functions

7. Options for model saving in CIM XML and UCTE format

8. Four cases of line connections

9. Transformers – flexgrid

10. Transformers – Load Flow tab

11. Transformers – Short Circuits tab

12. Short Circuit Calculation

13. Short Circuit Calculation - Lines

14. Short Circuit Calculation and Results Options

15. Short Circuit Calculation Results in Output Window

16. Power Flow Calculation Parameters

17. Power Flow Calculation Results Tree

18. About PSA Implementation PSA was completely made in C++ environment and contains only one executive file, i.e. without DLL files from other programming languages. It doesn’t require.Net Framework. Standard Windows libraries and WinAPI are used (without MFC, ATL, WTL...). PSA 4.0 was made in VS2010, so that, SP2 for WinXP has to be installed on workstation.

19. PSA References It has been used by Serbian, Macedonian and Montenegro Transmission System Operators during last six years. Studies: Wind park Vardenik (Serbia) integration into transmission system CHP Zenica (Bosnia and Herzegovina) integration into transmission system Versions 3.x were used for simulations of Southeast Europe dry-run coordinated auction office in 2008/2009.