Application of PMUs to monitor large-scale PV penetration infeed on frequency of 60 Hz Japan power system: A case study from Kyushu Island

Abstract

Recently, the large-scale photovoltaic (PV) penetration brings serious issues for system operators in monitoring and maintaining grid stability. The intermittent power output and loss of inertia property from high PV penetration critically affect the balance between generation and demand. These issues lead to larger frequency oscillations, generation tripping, and cascading failures. To overcome these challenges, this paper proposes an advanced application of phasor measurement units (PMUs) for monitoring dynamics of the system in the presence of high PV penetration. During such penetration, the data-driven analysis of the rate of change of frequency (ROCOF) is of great importance, reflecting the system stability. This approach is first demonstrated on Kyushu Island, and PMUs are installed at the domestic supply side. The contrastive scenarios of high-resolution PMUs recorded in each region are analyzed against different levels of PV penetration. The results reveal that monitoring system frequency and ROCOF variations not only indicate the oscillatory behavior of the grid, but also provide useful information for the wide-area dynamic stability. This paper also offers a recent overview of large-scale PV penetration infeed on frequency of the 60 Hz Japan power system, and it can be useful for improving a range of diagnostic/monitoring and control functionalities.