New Phylosophy for pole amplitude modulation in the three phase induction machines.

Abdel-kader, F.E; Abou Mobarka, A.E.; Abouel-Fadl, W.S.

doi:10.21608/erjm.1999.72452

New Phylosophy for pole amplitude modulation in the three phase induction machines.

Document Type : Original Article

Authors

¹ Dept. of Elect. Eng., Faculty of Eng. Minufiya University, Shebien El-Kom, Egypt

² Dept. of Elect. Eng., Faculty of Eng. Minufiya University, Shebien El-Kom, Egypt.

10.21608/erjm.1999.72452

Abstract

The induction motor is considered to be one of the best elecmcal motors
However up to now,it is difficult to control its speed by an ideal method, or
even by a method close to that of direct current motors. In spite of this
disadvantage, this motor is widely used when the load is not in need of
control of its speed over a wide range. Some loads need to change the speed
by a ratio of two or three times the rated value. In this case, it is possible to
use the Pole Amplitude Modulation to control the method of speed . This
method does not need high cost and keeps the motor characteristics in a high
grade. The previous papers on this subject mentioned that this technique can
be carried out by different methods of modulating the connections of motor
winding parts. There is a contradiction between theory and practice
seemed when verifying these connections experimentally on an actual
motor, so that the predicted speeds could not be obtained. So the motor
performance has been analyzed mathematically and physically. From
these results, the conditions necessary for motor windings, their
distribution and the method of connection have been obtained.