Electric Motor

                  An Electric Motor converts electrical energy into mechanical energy. Most electric motors operate through interacting magnetic fields and current-carrying conductors to generate force.

                  Electric Motors are found in applications as diverse as industrial fans, blowers and pumps, machine tools, household appliances, power tools, and disk drives. They may be powered by direct current (e.g. a battery powered portable device or motor vehicle), or by alternating current from a central electrical distribution grid or inverter. The smallest motors may be found in electric wristwatches. Medium-sized motors of highly standardize dimensions and characteristics provide convenient mechanical power for industrial uses. The very largest electric motors are used for propulsion of ships, pipeline compressors, and water pumps with ratings in the millions of watts. Electric motors may be classified by the source of electric power, by their internal construction, by their application, or by the type motion they give.

                   The physical principle of production of mechanical force by the interactions of an electric current and a magnetic field was known as early as 1821. Electric motors of increasing efficiency were constructed throughout the 19th century, but commercial exploitation of electric motors on a large scale requred efficient electrical generators and electrical distribution networks.

Types of Electric Motors: 

§  DC motors

§  Permanent-magnet motors

§  Brushed DC motors

§  Brushless DC motors

§  Coreless or ironless DC motors

§  Printed armature or pancake DC motors

§  Universal motors

§  AC motors

§  AC Motor with sliding rotor

§  Synchronous electric motor

§  Induction motor

§  Doubly-fed electric motor

§  Singly-fed electric motor

§  Torque motors

  §  Stepper motors

  §  Comparison

  §  Goodness factor

  §  Electrostatic motor

  §  Full size

  §  Nanotube Nanomotor

  §  Linear motors

  §  Spacecraft propulsive motors

  §  Servo motor