Comparison of Power Injection Strategies During Voltage Sags for Adaptive Control Based on Equivalent Impedance

Due to the increasing penetration of distributed energy resources, the Brazilian distribution grid code has been modified to specify how the integration between these elements and the grid should be carried out. Some of these modifications aim to expand operational capabilities, including the provision of ancillary services to the grid, for example. This paper explores this context, specifically, in relation to one such ancillary service that distributed resources can offer to the grid, which is the minimization of voltage sags. In pursuit of offering an efficient control method for this service, three different power injection methods will be compared for a distributed energy resource comprised of photovoltaic panels combined with a small-scale storage energy system. The objective is to determine which method is the most efficient in terms of trade-off between minimizing voltage sag and supplied power.