Power systems inertia evaluation associated with PV installation by frequency analysis of inter-area oscillation based on phasor measurements

Abstract

Recently, RES (renewable energy sources) have been introduced to realize a low carbon society. Installation of PV (Photovoltaics) is especially noticeable recently. RES, however, do not have inertia. If such sources increase, their influence on power system oscillations is a concern. Then, PMU (Phasor Measurement Unit) has been remarked to grasp a variable power system condition. In this study, changing of equivalent inertia of the power system is evaluated by identifying center frequency of inter-area oscillation derived by phasor difference frequency analysis using synchronized phasor information obtained from PMU. The center frequency is estimated by frequency analysis using FFT (Fast Fourier Transform) and inverse FFT. The result is evaluated quantitatively with reference to information of supply power and cumulative installation of PV. Additionally, the relationships between the center frequency and supply power or amount of global solar radiation are shown statistically.

Progress in control and coordination of energy storage system‐based VSG: a review

“…7, it calculates the RoCoF during contingencies and changes the power reference for the converter. The output of the controller emulated active power in terms of frequency deviation as in (6), where T ESS is the time constant of added filter for imitating the dynamic control for energy storage devices, and Δω is the RoCoF…”

“…The system could not accommodate rapid changes in the frequency during sudden load imbalance [5]. In the West Japan power system, a study on the estimated centre frequency in the system has discovered a relation between the decrement of inertia and high penetration of photovoltaic [6]. A similar problem is expected for other countries that have high renewable energies penetration in the grid.…”