Oscillation

A repetitive motion that can be either undamped, positively damped, or negatively damped.

Last Updated:  January 18, 2026

Version:  1.0.1

Generated:  January 19, 2026

Definition by PowerWorld

Source:

An oscillation is just a repetitive motion that can be either undamped, positively damped (decaying with time), or negatively damped (growing with time).

Types of oscillations include:

  • Transients: Usually high frequency and highly damped
  • Local plant: Usually from 1 to 5 Hz
  • Inter-area oscillations: From 0.15 to 1 Hz
  • Slower dynamics: Such as AGC, less than 0.15 Hz
  • Subsynchronous resonance: 10 to 50 Hz (less than synchronous)

In the context of power systems, Oscillation is an umbrella term that includes resonance.