DC-breaker for a multi-megawatt Battery Energy Storage System

Energy storage will gain importance in the future power system due to increased amount of renewables. In this paper, a utility scale Battery Energy Storage System (BESS) for megawatt utilizing a high voltage and a high power Voltage Source Converter (VSC) is proposed to be able to inject/consume the required power and energy to the grid. The batteries are both series and parallel connected on the DC-side of the VSC. In order to obtain high reliability, high availability and safety of the BESS, this paper proposes and analyzes a distributed Solid-State DC Breaker protecting the BESS and its batteries.