Online Monitoring of Primary Frequency Regulation Capability of High-Proportion new Energy Power System

At present, high-proportion new energy power system has become the mainstream trend. Due to the gradual increase of frequency instability accidents, the power system frequency safety problem is prominent. It is urgent to master the true primary frequency modulation capability of heterogeneous frequency modulation resources, and to monitor the system's ability to withstand power disturbances online. This paper introduces the primary frequency modulation capability of the unit by utilizing the adjusted power at the frequency extreme point
$\alpha_{m}$
and the electrical power change at steady state
$\alpha_{\infty}$
. Similarly, the primary frequency modulation capability of the system is determined by considering the sum of the electrical power change of all units and load at the frequency extreme point
$\beta_{m}$
and steady state
$\beta_{\infty}$
. Additionally, a novel approach is presented to estimate the primary frequency modulation capability indexes through the construction of a first-order inertial frequency difference curve. The examples prove that the proposed method can accurately evaluate the primary frequency modulation capability of the units and the system, and can be applied to the online monitoring system to ensure the frequency safety of the system.