Slip-energy-recovery schemes and the use of pole-change windings

The paper considers the general effects that may be obtained when slip-ring induction motors incorporating pole-change windings are employed in slip-energy-recovery schemes. It is concluded that, in some instances, considerable reductions in the rating of the slip-energy-recovery equipment may be achieved. Alternatively, a significant increase in the range of operation may be obtained, without the need for a proportionate increase in the rating of the slip-energy-recovery apparatus.