Improvements in the Voltage Stability of a Microgrid due to Smart FACTS ? an Approach from Resilience

SERRANO, BENJAMÍN RODOLFO; MOLINA, MARCELO GUSTAVO; PAREDES TAPIA, LUIS ANGEL

Quito

Conferencia; IEEE Andean Conference Technology and innovation , Ecuador 2020; 2020

IEEE Andescon

Flexibility as well as other characteristics of electric Microgrids (MGs) have allowed, from the point of view of supply, a greater presence of distributed generation (DG) systems through Distributed Energy Resources (DERs). In the context of demand this allows the connection of different types of static and dynamic loads. However, the increase in dynamic loads brings with it problems such as a high reactive power requirement, which results in difficulties to maintain voltage stability in the MG. Besides, the operational transition from the MG to the isolation considerably hinders control actions of the DERs. Thus, causing instability scenarios and in extreme cases the MG system voltage collapse, which seriously compromise its operational resilience. This paper proposes including smart FACTS (Flexible AC Transmission System) devices, particularly DSTATCOM (Distribution Static Synchronous Compensator), as mechanisms to substantially improve the MG voltage stability when it has to deal with an important presence of dynamic loads and, specifically, when there is a transition to isolated operation of MG. Using CIGRÉ microgrid test system, several case studies are considered and analyzed in the DIgSilent Power Factory. Results obtained show comparative improvements with the incorporation of DSTATCOM smart devices as regard the margin and behavior of MG voltage stability, as well as improvements in terms of operational resilience.