Effects of voltage unbalance and harmonics on drive systems with induction motor

Due to the significant share of the induction motors (IMs) in global electricity consumption, the study of the IM in different power supply regimes is the aim of this work. In practice, these electrical receivers are not supplied from ideal voltage systems, therefore the power quality (PQ) is an important aspect in analysing the operation of this type of motors. We proposed a methodology for analysing the effects of unbalanced distorted voltages not only on the technical parameters of the IM but also on the power supply as well as on the driven mechanical system. We identified some dependencies, in analytical forms, between the sizes of interest and the considered PQ disturbances. The results showed that the supply voltage disturbances have significant effects on the induction motor, both electrically and mechanically. These effects are amplified if the IM is running at loads below 50% of the rated load.