IEEE Transactions on Energy Conversion, Vol.23, No.2, 460-465, 2008
Experimental verification of critical-speed increase of single-phase induction machines via winding reconfiguration with solid-state switches
The concept of online electronic switching of windings will be applied to a single-phase induction motor with two separate windings with different pole numbers p(1) = 4 and p(2) = 6 and an auxiliary winding required for starting. During switchover from the low-speed winding to the high-speed winding, and vice versa, lasting less than a few milliseconds, small electrical torque and speed transients occur. Relying on closed-loop speed control, a smooth speed response is measured. This concept is, therefore, applicable to variable-speed drives, where a large speed range is desirable. Test data indicate that a speed-control range from 600 to 4000 r/min is obtainable with a single-phase induction motor.
Keywords:electronic switching of windings;induced voltage-frequency (E/f) control;increase of speed range;single-phase induction motor