On-Line Inertia Estimation for Synchronous and Non-Synchronous Devices

This paper proposes an on-line estimation method able to track the inertia of synchronous machines as well as the equivalent, possibly time-varying inertia from the converter-interfaced generators. For power electronics devices, the droop gain of the Fast Frequency Response (FFR) is also determined as a byproduct of the inertia estimation. The proposed method is shown to be robust against noise and to track accurately the inertia of synchronous generators, virtual synchronous generators with constant and adaptive inertia, and wind power plants with inclusion of energy storage-based frequency control.