Variable Speed Drives For Ac Machines

ABSTRACT Industrial drive applications are generally classified into constant-speed and variable-speed drives. Traditionally, AC machines have been used in constant-speed applications and DC machines were preferred for variable-speed. Induction machine with drive systems are widely used in applications such as pumps, paper and textile mills, elevators, electric vehicle, subway transportation, home appliance and wind generation. The three-phase squirrel cage induction motor is the mostly used motor type in the industry because of its good self-starting capability, simple and rugged structure, l…