Microgrid Black Start Capability and Transition to Grid-Connected Mode with Hardware-In-The-Loop Testing

Microgrids are ushering in a fundamental shift in how we perceive energy distribution and resilience within contemporary power networks. In response to the global drive for cleaner and more efficient energy options, microgrids have emerged as an exceptionally favorable substitute for conventional centralized grids. This paper presents a black start capability and seamless transition of a microgrid to the grid-connected mode. This requires appropriate control of the energy storage system, operating as a grid-forming inverter, and a synchronization procedure to make the transition from island to grid-connected mode possible. The soft start function of virtual impedance is adjusted in order to perform this transition with the order sent by Migrogrid Central Controller using a low band communication protocol. The results are tested using a hardware-in-the-loop with one battery energy stored commercial hardware and one photovoltaic generation, representing the grid following distributed energy sources.