Impact of photovoltaic systems on voltage stability in islanded distribution networks

Abstract

This work analyses the impact of photovoltaic generation on voltage stability margin in an islanded microgrid. An indicator of voltage collapse proximity, based on the maximum deliverable power, is used to study the contribution of photovoltaic generation to the voltage stability margin. In this context, the well-known power–voltage curves, also known as ‘nose’ curves, are developed, taking into account different levels of photovoltaic penetration. Furthermore, the effect of the power factor at the photovoltaic generators as well as the influence of the adopted model for such generators are also investigated. The results have shown that the photovoltaic generation can significantly affect the voltage stability margin.