The WBM Reconfiguration to Prevent the Instability on DC Shipboard Microgrids

Most innovative DC shipboard microgrids are designed to feed high-performance loads with advanced flexibility feature. The onboard loads not only require great amounts of power, but also their management results dynamically demanding. To this aim, tightly controlled power converters are employed to supply the loads by the filtered DC distribution. In such an islanded system, high-bandwidth converters and LC filters can negatively interact thus finally jeopardizing the ship operation. Smart procedures are to be conceived to preserve the system stability by reconfiguring the online shipboard loads. As the system stability depends on power/bandwidth of each load, the Weighted Bandwidth Method (WBM) is adopted to aggregate the effect of the several controlled loads. Once the WBM identifies two controlled loads as representative of the total dynamics demand, a 3D map results consequent. It reveals the loads combination to be fed without impairing the stability. If the Power Management System (PMS) exploits the outcomes from the 3D map to perform planned reconfigurations, the onboard stable operation is certainly ensured