A data-driven analysis of lightning-initiated contingencies at a distribution grid with a PV farm using Micro-PMU data

Abstract

In this paper, we conduct a data-driven experimental analysis of lightening-induced contingencies at a distribution grid in Riverside, CA, using data from three distribution level phasor measurement units, a.k.a, Micro-PMUs. The data was collected during four hours of a rainy day with several lightening strikes on October 24, 2016. Of particular interest was to analyze the impact and the response of a 7.5 MW PV farm. Due to the use of three Micro-PMUs, including one in an outlying area, we are able to distinguish system-wide events across the sub-transmission network against local events at the PV farm and its associated substation. Multiple interesting observations are made and the related causes are discussed. For example, based on the analysis of phase angle difference data, we observe that during at least one of the lightening events, there was a reverse power flow from the PV site to the substation due to a transient short-circuit caused by the surge arresters. This paper takes a first step in using Micro-PMU data to conduct a detailed analysis of how distributed energy resources (DERs) could be affected and and/or respond to the lightening-induced contingencies in distribution systems.