Inertia in Power Systems

1. Definition: Kinetic energy stored in the rotational masses of generators and motors synchronously connected to a power system.

2. Inertial Response: The kinetic energy is exchanged with the power systems (either released or absorbed) whenever there is an instantaneous imbalance between generation and load.

The rotational inertia/kinetic energy (KE) and inertia constant (H) are given by,