Soft restart of an adjustable speed drive after a shortdisconnection without any mechanical speed sensor

摘要

This high sensitivity of ASDs to power network disturbances iswell known by ASD manufacturers. They offer some mitigation strategiesagainst these disturbances. These strategies are based on `reducing asmuch as possible the effect of disturbances on the ASD behavior' orhaving a `ride-through capability in regards to disturbances' or a `softrestart'. Although some manufacturers seem to have mastered thesemitigation techniques, they have published almost nothing on thissubject to our knowledge. Therefore it is difficult to know whichmitigation strategies are used and what is the real level of ASDreliability in regards to disturbances. EDF has performed some researchin view of improving the reliability of ASDs under disturbances. Someresults of this study are presented in this paper. The effects ofvoltage dips and short supply interruptions on ASD behavior are firstexamined, then some mitigation control strategies are proposed