SOME SPECIAL ROTATING MACHINES

1. SOME SPECIAL ROTATING MACHINES • FRACTIONAL HORSE POWER MOTORS • MASS PRODUCTION • MOSTLY BASED ON BASIC PRINCIPLES • UNIVERSAL SERIES MOTOR • SINGLE PHASE INDUCTION MOTOR • RELUCTANCE MOTOR • STEPPER MOTOR

2. UNIVERSAL SERIES MOTOR LIKE DC SERIES MOTOR, MAGNETIC CIRCUIT = IRON SHEETS

3. CHARACTERISTICS OF „USM“ BY AC POWER SUPPLY IS THE BEHAVIOR WORSE

4. SPEED CONTROL OF „USM“ • EXAMPLE OF USE – HOUSEHOLD APPLIANCES: • VACUUM CLEANER • HAIR DRYER

5. SINGLE PHASE INDUCTION MOTOR ONE PHASE CANNOT PRODUCE ROTATING FIELD STATOR: like by 3phase ROTOR: squirrel cage BUT WHEN ONCE ROTATES, IT PRODUCES TORQUE

6. TORQUE-SPEED CURVEof single-phase induction motor SUBSTITUTION OF ONE PULSATING FIELD BY TWO ROTATING FIELDS

7. FUNCTION OF AUXILIARY PHASE ELIPTIC FIELD CAPACITOR – only for start for permanent run

8. SHADED POLE FOR SMALL STARTING TORQUE The current in short circuited ring produces own flux and thus makes field deformation

9. RELUCTANCE MOTORS FOR SMALL SYNCHRONOUS MOTORS – example CLOCK ROTOR: starting bars – squirrel cage Magnetic non-symmetry in d and q axes = shape of torque curve like by salient pole machines

10. STEPPER MOTOR FOR PRECISE POSITIONING WITHOUT FEED BACK LOOP STATOR: poles excited by DC pulses ROTOR: permanent magnet od DC windings

11. TORQUE BY STEPPER MOTOR