Question

A de series motor is connected to a constant-torque load, which may be considered to require a constant electromagnetic torque regardless of motor speed. Neglect the voltage drops due to

the armature and series-field resistances, the armature reaction, and the effects of saturation. (a) By what percent is the motor speed changed when the line voltage is reduced from 230 V to 200 V? (b) Repeat (a), assuming shunt motor. (c) State briefly what effects saturation might have on the answers to (a) and (b).Ans. (a) 13%; (b) *0

Fig: 1