Resonant Controllers to Achieve Torsional Stability: a Ship Case Study

Sub-Synchronous Torsional Interactions (SSTIs) characterize all the power systems with joint presence of rotating machinery and power converters. In this paper a ship equipped with gas turbines is considered as case study. It is investigated the possibility to avoid torsional instability thanks to the employment of Resonant controllers in the control system of the power conversion stage. Successful results are verified also in critical operation conditions. Black-outs can be prevented acting on the control loop and without the addition of redundant turbine-generator units in the network.