Dynamic Response Evaluation of a 20 MW Scale Dual Wound Machine Based Power System

摘要

Several power system technical architectures are being evaluated for the Navy's next generation all-electric warship. One proposed power system concept involves the use of dual-wound generators to power both the Port and Starboard side buses using different 3-phase sets from the same machine. However, due to the collocated sets of stator windings sharing a common rotor, there are inductive and electromechanical coupling mechanisms between the two sets of windings. This, in effect, couples the port and starboard electrical buses, resulting in the possibility of load changes and faults on one bus creating disturbances on the other bus. Thus, for this power system architecture to be implemented, the coupling between buses must be evaluated and managed to ensure the isolation that is required.In this work, a notional power system consisting of a 20 MW gas turbine connected to a dual-wound generator and two active rectifiers was considered. The generator and active rectifier models were implemented in MATLAB™ both using average value modeling and switching (space vector modulation) simulation models. The system was analyzed with both a permanent magnet synchronous machine (PMSM) and a wound rotor synchronous machine (WRSM) acting as the generator. The frequency dynamics of the system between the load on one side and the dc voltage on the other side are studied, and possible mitigation strategies are proposed.