Test Cases Library of Power System Sustained Oscillations

Forced oscillation case F_4_2 (Back to the homepage)

In this forced oscillation case, the source of oscillations is at generator 79.


System model:

  • Generator 79 is in GENROU model.
  • All other generators are in GENCLS model.
  • Parameter D for all generators equals 4, except for generator 79 whose D equals 0.
  • All loads are in constant MVA model.

  • Small signal analysis:

  • All natural modes have reasonably good damping.
  • The system has natural modes at 0.84Hz and 0.86Hz.

  • External force:

  • Forced oscillation is injected into excitation system as a sinusoidal signal at generator 79 with a frequency 0.85Hz.
  • The gain of the external force is tuned such that the largest peak-to-peak value among all generators' active power outputs is about 205MW.

  • Mountain View

    Figure 1. Block diagram of the external force

    Mountain View

    Figure 2. WECC 179-bus power system