Using Battery Energy Storage Systems for Load Balancing and Reactive Power Compensation in Distribution Grids

The paper evaluates current equipment conditions and electricity quality in distribution grids. It proposes an innovative technical solution to use battery energy storage systems (BESS) for load balancing and reactive power compensation in distribution grids. Analysis of the effective Russian standards identifies the lack of regulatory requirements to BESS functionality. Given the latest advances made by manufacturers in solving distribution-grid problems, the authors propose a combination of primary and secondary BESS functions. The paper analyzes the main reasons behind unbalanced loads as well as how to balance them. A comparative parametric analysis of the conventional balancing devices, such as capacitor batteries (CB) and BESS helped to draw requirements to the rated capacity of BESS converters for solving the stated problems. It is additionally found that running the secondary functions under analysis will not affect the service life of storage systems. The paper states the practical significance and the efficiency of the proposed solution. BESS can radically change the approach to load balancing by compensating the negative- and/or zero-sequence currents as well as by compensating the reactive power in distribution grids.