Question 11 Assume that the motor is reconnected separately excited, as shown in Figure Q11. It has a fixed field voltage VF of 240 V and an armature voltage Va that can be varied from 120 to 240 V. IF RA IL 0.40 2 Radj VE = 240 V Rf = 100 N EA V = 120 to 240 V Lf Figure Q11 a) What is the no-load speed of this separately excited motor when Radj = 175 Q and 1) VA = 120 V, 2) VA = 180 V, 3) VA = 240 V b) What is the maximum no-load speed attainable by varying both VA and Radj? c) What is the minimum no-load speed attainable by varying both VA and Radj?

Question 11 Assume that the motor is reconnected separately excited, as shown in Figure Q11. It has a fixed field voltage VF of 240 V and an armature voltage Va that can be varied from 120 to 240 V. IF RA IL 0.40 2 Radj VE = 240 V Rf = 100 N EA V = 120 to 240 V Lf Figure Q11 a) What is the no-load speed of this separately excited motor when Radj = 175 Q and 1) VA = 120 V, 2) VA = 180 V, 3) VA = 240 V b) What is the maximum no-load speed attainable by varying both VA and Radj? c) What is the minimum no-load speed attainable by varying both VA and Radj?

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter12: Power System Controls

Section: Chapter Questions

Problem 12.4P

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