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Error 163 | [PSS®E] | No swing bus present


Relevant software:

PSS®E


Emitted message:

No swing bus present in loaded case file

Description:​

This error indicates that the PSS®E case file (.sav) loaded for the simulation does not contain a swing bus (also known as a slack bus, reference bus or type 3 bus).

In a standard power flow analysis, there must be exactly one swing bus. This bus serves as the reference for voltage angle and balances the total active and reactive power in the system. Having no swing bus makes the power flow problem mathematically unsolvable.

danger

The simulation will fail to solve as PSS®E cannot converge without a swing bus.

Possible impact:​

  • The simulation will terminate with a convergence error.
  • No valid power flow solution will be obtained.

Potential fixes:​

  • Review PSS®E Case File: Open your .sav file in PSS®E and examine the bus data.
  • Designate a Swing Bus: Identify a suitable generator bus to act as the system reference. Change its bus type to 3.
  • Save and Re-run: Save the corrected case file and re-run the simulation in gridmo.