Presentation on AC Motors

PRESENTATION ON:

INDUCTION MOTORPRESENTING BY:

MUHAMMAD NAVEED ASIM

ELECTRIC MOTOR

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An electric motor is an electromechanical device that converts electrical energy to mechanical energy.

CLASSIFICATION OF MOTORS

Electric Motors

Alternating Current (AC) Motors

Direct Current (DC) Motors

Synchronous Induction

Three-PhaseSingle-Phase

Self ExcitedSeparately Excited

Series ShuntCompound

AC MOTOR: INDUCTION MOTOR

Most common motors in industry

Advantages: Simple design Inexpensive High power to

weight ratio Easy to maintain Direct

connection to AC power source

MOTOR WINDING

AC-SINGLE PHASE MOTOR WINDING

AC-THREE PHASE MOTOR WINDING

SINGLE PHASE AC MOTOR WINDING

AC-SINGLE PHASE MOTOR WINDING METHOD

1 HP SINGLE PHASE MOTORNO.OF SLOTS IN STATOR

CURRENT 1 AMPARERUN PER MINUTE 1450/1500

VOLTAGE 230-250FREQUENCY 50 Hz

ACCORDING TO WINDING METHOD

REQUIRED INFORMATION:NO. OF POLESNO. OF SETS

NO. OF COILS IN SETSCOIL PICH IN EVERY SET

TURNS OF COILWIRE SIZE OF EVERY SET

FORMULA

WE CAN FIND.NO. OF POLES = 2 * 60 *FREQUENCY/RPM

2 * 60 *50/1500 = 4 POLES

NO. OF SETSIF POLES ARE 4 AND RPM 1500 AND VOLTAGE 230

TO 250CAPACITOR START MOTOR

KNOWN:WINDING WILL BE DOUBLE

1. STARTING WINDING2. RUNNING WINDING

NO. OF COILS IN A SET COILS OF STARTING WINDING = 3COILS OF RUNNING WINDING = 3

STARTING WINDING COILS 3 * 4 = 12RUNNING WINDING COILS = 3 *4 = 12

TOTAL COILS IN MOTOR = 24

NO. OF TURNS OF STARTING AND RUNNING WINDINGS

STARTING WINDINGTURNS = 100PICHES 1-7, 2ND 1-5, 3RD 1-3SUM= 3+5+7=15TURNS BIG COIL=TOTAL TURNS *

COIL PICH/SUM OF PICHES1ST PICH(1-7) = 100 * 7/ 15 = 46

TURNS2ND PICH(1-5) = 34 TURNS3RD PICH(1-3) = 20 TURNS

TOTAL = 46 + 34 + 20 = 100

USED NARROW WIRES.W.G 23

RUNNING WINDING

TURNS = 75PICHES 1-7, 2ND 1-5, 3RD 1-3SUM= 3+5+7=15TURNS BIG COIL=TOTAL TURNS * COIL

PICH/SUM OF PICHES1ST PICH(1-7) = 75 * 7/ 15 = 35 TURNS2ND PICH(1-5) = 25 TURNS3RD PICH(1-3) = 15 TURNS

TOTAL = 35 + 25 + 15 = 75USED THICK WIRES.W.G 21

COIL PICH AND SIZE OF WIRE

COIL PICHWINDING PICH = NO. OF SLOTS +1/NO. OF

POLES

(32 + 1)/4 = 72ND = 7-2 = 53RD = 5-2 = 3

SIZE OF WIREEXAMPLE:MOTOR HP = 20 HPVOLTAGE = 400VI = (20 *

746)/400=37.3AAREA = 37.3/2000 =

0.01865AREA IS SQUARE PER INCHWIRE SIZE (S.W.G) = 8

SINGLE PHASE AC MOTOR RUNNING WINDING

SINGLE PHASE AC MOTOR WINDING

CONECTIONS OF INTERNAL COILS

HOW SINGLE PHASE MOTOR WORKS

THREE PHASE MOTOR WORKS

THREE PHASE MOTOR WORKS