Fault Ride Through in PMSM Drive Based on Dynamic Voltage Restorer and Ultracapacitor

Abstract

In this paper two devices are proposed for fault ride through (FRT) of an adjustable speed drive (ASD) connected to a distribution system. The FRT ability of the system is tested first by connecting a dynamic voltage restorer (DVR) between the ac supply and the ASD, then by connecting an ultracapacitor with the DVR. Two types of faults are investigated, namely; a voltage swell and a three –phase ground fault. The ASD performance during these faults and the current and voltage harmonics are demonstrated with DVR only and after connecting the capacitors. The active and reactive power and the dc link voltage are also presented. Conclusions are drawn concerning the validity of adding the capacitor with the DVR for FRT.