WOLF-I Image Welcome to the WOLF-I project page. This project focuses on studying and analyzing the role of IBRs in the damping of inter-area oscillations. Our goal is to understand the dynamics of these oscillations and develop strategies and tools to mitigate their impact on power systems.

In Europe, inter-area oscillations are a resonance phenomenon that occurs between generating units in different regions of the European continental grid. These units oscillate at low frequencies (typically between 0.1 and 1 Hz), causing fluctuations in various electrical parameters, including active power, voltage, and frequency.

The most poorly damped inter-area mode in Europe is currently the East-Centre-West inter-area mode, where oscillations in the Iberian Peninsula and Turkey are out of phase with central Europe.

alt text

The animation demonstrates the evolution of an East-Center-West oscillation pattern across four countries. In this context, the chosen measure to represent these oscillations is the evolution of rotor speed and position.

  • Germany (green)
  • France (red)
  • Spain (blue)
  • Turkey (black) (Note: blue and black lines overlap)

Each country’s oscillation reflects its phase and amplitude relative to the others:

  • Germany oscillates with the maximum amplitude and is in opposite phase to the other countries.
  • France oscillates in phase with Spain and Turkey but with a smaller amplitude.
  • Spain and Turkey exhibit identical amplitudes and oscillate perfectly in phase.

Damping Effects on Oscillations

The animation further illustrates how the system behaves under three damping scenarios:

  1. Zero damping: Oscillations persist indefinitely, making the system unstable.
  2. Positive damping: Oscillations gradually subside, achieving a stable and controllable state.
  3. Negative damping: Oscillations grow uncontrollably, leading to system instability and potential failure.

From an operational perspective, positive damping is the desired condition. It ensures that oscillations diminish over time, enabling operators to maintain a predictable and controllable system. In contrast, zero or negative damping jeopardizes stability and complicates system management.

These oscillations represent an exchange of energy between different areas of the grid. In the example, France, Spain, and Turkey oscillate in sync, collectively exchanging energy with Germany. The amplitude differences highlight the varying levels of participation in this energy exchange.