On Determining Critical System Ramp Capability Requirement in High PV Penetration Network Using Graphical Method

Abstract

Increasing effort of solar power integration to the grid could be accelerated towards sustainability goal. However, high PV penetration ratio (PVR) in turn critically reduces system frequency response performance of an existing power system due to reduction of on‐line rotating generators. Besides intrinsic system inertia, system RC plays a vital role in dynamically securing the power system operation subject to large PV disturbances. This study proposes a graphical method to determine critical values of system RC requirement with respect to the anticipated PVR and PV ramp‐down rate of disturbance; both of which should be forecastable, in practice, in each operating time interval. Impact of PVR on dynamic performance of a power system, through the effective time‐varying of system inertia and governor response characteristic has been examined. The results of the analyses on graphical display will be useful for system operators to prepare enough system RC, economically well in‐advance through Unit Commitment program, to ensure system dynamic security, complying with the N‐1 contingency constraint. In addition, the proposed graphical display can reveal whether the curtailment of aggregated PV's output generation is necessary for that time interval. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.