Robust unit commitment with characterised solar PV systems

Abstract

This article addresses a critical issue on the robust unit commitment (RUC), which is the construction of an accurate and reliable uncertainty set for solar photovoltaic (PV) systems. The classic robust unit commitment (CRUC) provides an inaccurate and unreliable model for the highly intermittent solar generations. However, the authors' proposed uncertainty set utilises the forecast models that rely on the clear-sky and overcast solar forecasts, which are more accurate and reliable. The uncertainty set for solar generations is constructed based on the type of day, levels of daily uncertainty index (DUI) and daily energy index (DEI), and the uncertainty level of solar ramps. The test results on the IEEE 118-bus test system demonstrate that (i) using DEI and DUI reliably and efficiently manages and reduces the cost for highly uncertain and overcast day compared to the CRUC and (ii) the RUC cost is much sensitive to the selected level of DUI and DEI than the uncertainty level of the solar ramps.