SKEE 2413 PERDANA FINAL EXAMS 201520162 Q4 SCHEME.pdf - Solution(a i ii Power flow in a shunt-connected dc motor Suggest a method to control the speed

# SKEE 2413 PERDANA FINAL EXAMS 201520162 Q4 SCHEME.pdf -...

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Solution (a) i. ii. Power flow in a shunt-connected dc motor Suggest a method to control the speed? For shunt-connected DC motors, speed control can be made by (a) varying the field current (danger of open circuit in field circuit – I A very large) (b) inserting resistance in series with the armature. (c) Variation of supply voltage – not suitable for shunt motor (field current offset by V T ) iii. R adj or series resistance a rheostat that is in series with the armature: Inserting resistance in series with the armature We denote the total resistance as R A , which consists of the control resistance plus the resistance of the armature winding. The torque-speed relationship for a shunt-connected motor is Starting controls for shunt dc motors usually place resistance in series with the armature to

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• Fall '20
• Magnetic Field, Electric motor