UNIT – I
Introduction: concept of electric drives, types of drives, speed torque characteristics of various electric drives. Starting methods for DC shunt and series motor and three phase induction and synchronous motors, expressions for starting current and starting torque. Electric braking of electric drives, types of braking, speed torque characteristics of electric drives under braking conditions. Reversal of electric drives.

UNIT-II
Speed control: fundamental parameters of speed control of dc motors. Field control and armature control characteristic constant torque and constant HP Characteristics a.c. motors variable frequency pole changing variable resistance in stator and rotor circuit, voltage injection in the rotor circuit characteristics.

UNIT-III
Transient condition basic concept regarding transients in drives analysis of transient condition during starting braking reversal and sudden loading of dc drives energy involved in transient process analysis of transient behavior of the phase induction drive while starting and braking.

UNIT-IV
Solid state control advantage of using solid state control drives in industrial field principle of working block diagram and characteristics obtained in dc shunt, series and compound motors. Three phase induction and synchronous motor for adjustable speed drives.

UNIT-V
Estimation of motor rating and drive selection: types of duty cycles calculation of motor rating for various duty cycles load diagram. Load equalization flywheel calculations permissible frequency of starting of squirrel cage motor general consideration in selection of drive for industrial applications.