Mhj. Bollen, CHARACTERIZATION OF VOLTAGE SAGS EXPERIENCED BY 3-PHASE ADJUSTABLE-SPEED DRIVES, IEEE transactions on power delivery, 12(4), 1997, pp. 1666-1671
It is shown in this paper that voltage sags experienced by three-phase
loads like adjustable-speed drives, can be classified into four types
. Each sag can further be characterized by a magnitude and a phase-ang
le jump. Relations between fault type, sag type, and load connection a
re presented. The transfer of sags through transformers is discussed.
Magnitude and phase-angle jump of sags are directly related to the vol
tage in the faulted phase, or between the faulted phases, at the point
-of-common coupling between the load and the fault.