Battery Energy Storage System based Voltage and Frequency Control of An Island Distribution Network

One of the blocking forces of renewable sources (RES) is its volatile nature and
system condition associated with low consumption and high production periods, which tend to deteriorate the power quality by voltage increase, frequency fluctuations etc., and in addition, it may prevent further penetration of RES. Installation of a battery energy storage system (Lithium‐ion BESS) is proposed for the considered distribution network in Madeira Island, as one of the solutions for effective integration of renewable generation, improvement of the quality of power and also faster response for establishing power balance. The main objective of this research is to provide an efficient and reliable control strategy by using the BESS to alleviate both the voltage and frequency violations. The BESS is charged during excess PV generation, thereby mitigating the voltage rise issues and the stored energy is discharged for any under‐voltage and under‐frequency issues. Although frequency events can be controlled by the BESS, its influence will be not perceptible, because the highest generation group imposes the grid frequency in the island. Nevertheless, if the system is replicated on a higher scale (i.e., more low voltage distribution substations) the contribution for frequency control will certainly be more substantial. The system modeling and the simulation studies have been carried out in DIgSILENT power factory software. The results are obtained for particular BESS size acting towards mitigating voltage and frequency fluctuations. In addition, a sensitivity analysis is carried for studying the affect of various BESS sizes and system loading conditions on reverse power flow and proposed control strategy.