Battery energy storage sizing With Respect to PV-induced power ramping concerns in distribution networks

In the past few years, high penetration of Renewable Energy Sources (RES) in transmission and distribution networks has challenged the stability of the power grid due to the intermittent nature of the sources, mainly wind and solar energy. A Battery Energy Storage System (BESS) can be considered as a fast-acting backup source to accommodate higher penetration of RES. A BESS has better ramping characteristics than traditional generators to smooth out the RES fluctuations. The limitation of power ramping capability of PV plants in meeting ANSI C84.1 standard in distribution networks is addressed in this paper. The BESS is added in parallel with the PV plant with the aim of minimizing voltage variations of the grid at the Point of Common Coupling (PCC). Due to grid characteristics, different power ramping capability of the BESS is required to mitigate PV plant intermittency. An analytical method is introduced to find the required BESS power and energy ratings considering network characteristics, geographical variables like wind speed, and size of the PV plant. The IEEE 13-bus system is selected as a test case for investigating the voltage sensitivity to the injected active power. Finally, the minimum required ratings of a BESS is calculated and validated with a common BESS sizing method using historical data.