Instability can occur when an induction machine is supplied by a volta
ge source inverterbased PWM drive operating in an 'open loop' mode, pa
rticularly if the machine is lightly loaded. A form of space vector mo
dulation is described in this paper that can be used to improve machin
e stability substantially. The modulation range of this technique is l
imited, however different methods of overcoming this limitation are di
scussed.