A Novel Unit Protection Scheme for Grid Connected BESS Using Wavelet Transform

A grid Scale battery storage System (GSBS) is essential to enhance grid stability with the integration of renewable energy sources (RESs) that lacks inertia and following a disturbance may lose stability. Hence, battery stacks with large power capacities are installed with several control techniques built into them. The fault current rise may be delayed or limited due to the presence of such a control technique causing a delay in fault detection and sometimes, the fault may not be detected. In this paper, a methodology using wavelet transform is applied to both ends of current data to detect the fault occur on the DC cable. The results obtained from the simulation of a 700 V, 25 KW grid-connected system, in MATLAB/SIMULINK 2023a, reveal the proposed method is not affected by the control techniques and can detect the high resistance fault accurately. The improved reliability of the proposed technique ensures the grid-scale storage requirements.