SPECIAL MACHINES

SPECIAL MACHINES: 

UNIT- I

Stepper Motors Constructional features, Principle of operation, Modes

of excitation torque production in Variable Reluctance (VR) stepping

motor, Dynamic characteristics, Drive systems and circuit for open

loop control, closed loop control of stepping motor.

UNIT- II

Permanent Magnet Synchronous Motors (PMSM) and Switched

Reluctance Motors (SRM)

PMSM: Power electronic controllers, Torque speed characteristics,

Self control, Vector control, Current control.

SRM: Constructional features, Principle of operation. Torque equation,

Characteristics, Control Techniques, Drive concept.

UNIT- III

Permanent Magnet Brushless DC Motors Concept of electronic

commutation, Hall sensors, Optical sensors, back emf detection,

Multiphase Brushless motor, Square wave permanent magnet brushless

motor drives, Torque and emf equation, Torque-speed characteristics,

Speed control by microcontroller.

UNIT- IV

Servomotors and AC Tachometers Servomotor – Types –

Constructional features – Principle of Operation – Characteristics -

Control – Microprocessor based applications.

AC Tachometers: Permanent magnet ac tachometer, AC induction

tachometer, Schematic diagrams, Operating principle.

UNIT- V

Linear Motors Linear Motors: Linear Induction Motor (LIM)

Classification – Construction – Principle of operation – Concept of

Current sheet –Goodness factor – DC Linear Motor (DCLM) types –

Circuit equation – DCLM control-applications.

REFERENCES

1. Miller, T.J.E. “Brushless Permanent Magnet and Reluctance Motor

Drives”, Clarendon Press, Oxford, 1989.

2. Kenjo, T, “Stepping Motors and their Microprocessor control”,

Clarendon Press, Oxford, 1989.

3. Naser A and Boldea I, “Linear Electric Motors: Theory, Design and

Practical Application”, Prentice Hall Inc., New Jersey,1987.

4. Special Electrical Machines-K.Venkataratnam- University press.

5. Floyd E Saner,”Servo Motor Applications”, Pittman USA, 1993.

6. Kenjo, T and Naganori, S “Permanent Magnet and brushless DC

motors”, Clarendon Press, Oxford, 1989.

7. Generalized Theory of Electrical Machines – P.S.Bimbra-Khanna

publications-5th edition- 1995.