Effective Inertia Constant: A Frequency-Strength Indicator For Converter-Dominated Power Grids

The system inertia constant is the predominant indicator for power system frequency strength, but fails to account for non-inertial contributions such as fast frequency response. In this paper, the effective inertia constant is proposed as a new indicator to account for the contribution from both synchronous generators and power-electronic interfaced sources. Time-domain simulations show that the effective inertia constant is a better indicator for frequency nadir than the conventional inertia constant.