A Novel Protection Coordination Strategy for DC Microgrids

The coordination strategy in DC Microgrids (MGs) is the sequential operation of the protection devices. Relay coordination is a challenging task, as it isolates the faulty parts with the minimum operation of relay and circuit breakers. This paper presents an inverse time-current curve (ITCC) based efficient coordination scheme for radial multi-bus grid-connected DC MGs. The proposed scheme rapidly isolates the faulty parts and restores the non-faulty parts to maintain the reliability of the system. This scheme does not need a communication network between solid-state circuit breakers (SSCBs) and power electronics converters. This reduces the implementation complexity and the cost of the proposed scheme. The performance of the proposed coordination scheme is validated using a 750 V four bus solar and energy storage sources (ESS) integrated radial DC Microgrid (MG) in MATLAB/Simulink platform.