Electrical Machines 1
ES-201
Principles of EMEC: Fundamentals of Magnetic Circuits Energy in Electro-Magnetic Systems Flow of Energy in Electro-Mechanical Devices Energy and co-energy in Magnetic field Singly and doubly excited systems Electromagnetic and Reluctance Torque DC Generators: Constructional features Armature winding details lap & wave connections EMF equation separately excited shunt series and compound connected D.C. generators process of voltage build up in shunt generators Characteristics and applications of separately/self-excited generators
DC Generators (Contd.): Armature Reaction Demagnetizing and Cross-magnetizing armature MMF Interpoles and compensating windings commutation process and its improvement D.C. Motors: Speed and Torque Equation of D.C. motors Characteristics of D.C. series shunt and compound motors and their applications Starting and speed control of D.C. motors Braking of D.C. motors Efficiency and testing of D.C. Machines Introduction of D.C servo motor and permanent magnet / brushless D.C. motors
Single phase Transformers: Transformer construction and practical considerations Equivalent circuit(Exact and approximate) per unit values Phasor diagram Transformer testing : open circuit test, Short Circuit test, Sumpner’s test Efficiency and voltage regulation All day efficiency
3 phase Transformers: Three-phase Bank of Single-phase Transformers Parallel operations of 1-phase and 3-phase transformers load division between transformers in parallel Three winding transformers Zigzag connections vector grouping with clock convention tertiary winding tap changing phase conversions-3phase to 2 phase and 3phase to 6 phase Special Purpose Transformers: Auto-transformers. Welding, Traction, Instruments and pulse Transformers