19EE2010
Special Electrical Machines
L 3
T 0
P 0
C 3
Course Objectives: 1. To gain knowledge on construction and working of various special electrical machines. 2. To study the characteristics of various special electrical machines. 3. To learn the control techniques for the operation of special electrical machines. Course Outcomes At the end of this course, students will demonstrate the ability to 1. Select an energy efficient linear or rotary motor based on the characteristics of the load & applications. 2. Incorporate the correct control technique to the machine for efficient operation. 3. Analyze the behavior of the machine for the applied control technique. 4. Improve the performance of the motor by enhancing the operating conditions. 5. Explain the theory of travelling magnetic field and applications of linear motors. 6. Explain the significance of electrical motors for traction drives. Module 1: Stepper Motor (8 hours) Introduction - Different Types – Construction – Theory of Operation – monofilar and bifilar windings – Modes of excitations Modes of excitations – Single and multi-stack configurations – Torque equations – Characteristics – Microprocessor control of stepping motors – Applications. Module 2: Switched Reluctance and Synchronous Reluctance Motors (8 hours) Constructional features – Types – Axial and radial air gap motors – Operating principle – Reluctance – Phasor diagram – Characteristics – Switched reluctance motor constructional features – Rotary and Linear SRMs – Principle of operation – Torque production – Characteristics – Power Converters and their controllers – Rotor position sensing methods – Sensorless operation – Applications. Module 3: Permanent Magnet Brushless DC Motor (8 hours) Permanent Magnet materials – Magnetic Characteristics – Permeance coefficient -Principle of operation – Types – Magnetic circuit analysis – EMF and torque equations –Commutation - Power controllers – Motor characteristics and control – Applications. Module 4: Permanent Magnet Synchronous Motor (7 hours) Principle of operation – Ideal PMSM – EMF and Torque equations – Armature reaction MMF – Synchronous Reactance – Sinewave motor with practical windings – Phasor diagram – Torque/speed characteristics – Power controllers – Applications. Module 5: Electric Motors for Traction Drives (7 hours) AC series motors – DC motors –Single sided linear induction motor for traction drives – Comparison of AC and DC traction – Applications. Module 6: Axial Flux based Motors (7 hours) Principles of AFPM machine – Material and Fabrication – Analysis with and without iron & stator cores – Control Mechanisms – Applications. Text Books 1. Venkataratnam. K., “Special Electric Machines”, CRC Press, Boca Raton, U.S.A., 2008. 2. Janardanan. E. G, “Special Electrical Machines”, Prentice Hall of India, New Delhi, 2014. Reference Books 1. Kenjo, T, “Stepping Motors and their Microprocessor Control”, Clarendon Press, Oxford, 1989. 2. Krishnan .R, “Switched Reluctance Motor Drives”, CRC Press, Boca Raton, U.S.A., 2001. 3. Kenjo.T, Naganori. S “Permanent Magnet and Brushless DC Motors”, Clarendon Press, Oxford, 1989. 4. Miller, T.J.E. “Brushless Permanent Magnet and Reluctance Motor Drives”, Clarendon Press, Oxford, 1989. 5. Jacek F. Gieras, Rong-Jie Wang & Maarten J. Kamper, “Axial Flux Permanent Magnet Brushless Machines”, Springer Netherlands, 2nd Edition, 2017.
ELECTRICAL AND ELECTRONICS ENGINEERING (2020)
