Analysis of Effects of Three-Phase Voltage Unbalance on Induction Motors with Emphasis on the Angle of the Complex Voltage Unbalance Factor

A Centralised Control Method for Tackling Unbalances in Active Distribution Grids

“…2% for 95% of the week according to EN50160 [23]. To avoid this non-convexity, we approximate VUF by the negative voltage sequence, assuming the positive voltage sequence is very close to 1.0 when expressed in per-unit [24]. Therefore, the following balancing constraint is used…”

Transposition and Voltage Unbalance in High Phase Order Power Transmission Systems

“…Therefore, an HPO complex voltage unbalance factor (CVUF) could be useful to determine the derating of HPO motors with voltage unbalance. CVUFs are discussed in the literature [24,25]. However, it should be noted that even a CVUF may not be a sufficient indication of voltage unbalance [26,27].…”

“…The generalized VUF also affords an appropriate impact measure. Further studies may also research a CVUF to give a better indication of the effects of voltage unbalance on rotating loads [24,25].…”

Precise Assessment of Performance of Induction Motor under Supply Imbalance Through Impedance Unbalance Factor

“…Since the IM are connected either in star without neutral or in delta so the zero sequence component is absent and hence negative sequence component becomes the primary cause of voltage unbalance [15]. Hence it can be said that voltage unbalance is a superposition of negative sequence voltage over positive sequence voltage.…”

“…This method reduces the complexity arises in transforming phase to sequence component and vice versa and also investigates the increases in losses under unbalance supply voltage condition. In all of these aforementioned studies [5][6][7][8][9][10][11], either the percent voltage unbalance (PVU) defined by NEMA [12], or VUF defined by IEC [13] [15], special emphasis is placed on the effect of the angle of CVUF on the performance of IM and most favourable and worst case for derating factor and maximum allowable slips are discussed whereas in [16] normalized negative sequence component is used in substitution to VUF to judge the effect of unbalance. Different definitions of the voltage unbalance are analyzed in [17] and by using these definitions the variation of the unbalance voltage in 3-D locus are plotted to reduce the range of the variation of terminal voltages.…”