ESO-based FTC strategy via dual-loop compensations for 5-phase PMSG integrated tidal applications

Abstract

Using multiphase permanent magnet synchronous generators (PMSG) is able to strengthen whole reliabilities of the tidal stream energy systems. Even so, advanced fault-tolerant control designs are also needed for a further enhancement of multiphase PMSG integrated tidal stream turbine under harsh sea water environments. Thus, extended state observers are used to develop a fault-tolerant control strategy towards a trapezoidal five-phase PMSG incorporated tidal stream application. This FTC strategy considers open circuit of a phase and a switch in the five-phase PMSG and its connected converter. To attenuate influences due to these faults, a dual-loop compensation mechanism is performed via extended state observers. System adaptation to swell effects of the tidal stream and feasibility of the proposed FTC strategy are verified through a 1.5 MW simulation setup.