Theory of the brush-shifting A-C motor — III: power-factor correction

In the preceding papers¹ of this series a method was described for determining the circle diagram and predicting the characteristics for the brush-shifting motor as it is used when the brushes are shifted to control speed. This paper extends the earlier work to show how the motor can be used to correct power factor. The range and limitations for this condition of operation are revealed from the circle diagram of the motor which has been developed and verified experimentally. Characteristics of the motor when used in this manner are presented.