Electrical Machines 1 Semester 4 (SE Second Year) BE Electrical Engineering University of Mumbai Topics and Syllabus

• Magnetic field, Magnetic circuit, Numerical from series parallel magnetic circuit, Flux linkage, Inductance and energy, Faraday’s laws, Hysteresis and eddy current losses.

Magnetic field, Magnetic circuit, Numerical from series parallel magnetic circuit, Flux linkage, Inductance and energy, Faraday’s laws, Hysteresis and eddy current losses..

• Construction of machine, Armature winding, Principle of operation, MMF and flux density waveforms, Significance of commutator and brushes in DC machine, EMF and Torque equation, Methods of excitations, Armature reaction, Methods to minimize the effect of armature reaction, Process of commutation, Methods to improve commutation.

• Characteristics of DC Motors, Concept of braking of DC separately excited motors (Rheostatic, Regenerative and plugging).
• Starters for shunt and series motors, Design of grading of resistance for starter, Speed Control, Losses and efficiency, Applications of DC motor.

• Retardation, Brake load, Swinburne, Hopkinson’s, Field test.

• Review of EMF equation, Equivalent Circuit and Phasor diagram of Transformer. Voltage Regulation of Transformer: - Voltage Regulation, Condition for Zero Voltage Regulation, Condition for Maximum Voltage Regulation.
• Transformer Losses and Efficiency - Losses, Efficiency, Condition for Maximum Efficiency, Energy Efficiency, All day Efficiency, Separation of Hysteresis and Eddy current losses Testing of Transformer: - Polarity Test, Load Test, Review of OC and SC test, Sumpner’s Test, Impulse test.
• Autotransformer:- Autotransformer Working, Advantages of Autotransformer over Two winding Transformer,
• Disadvantages Parallel Operation: No load Operation,
• On load Operation:- Equal Voltage Operation and Unequal Voltage Operation Introduction to High Frequency Transformer, Pulse Transformer, Isolation Transformer and its applications.