% Design of stator of 3-phase induction motor

% calculate the main dimension of the air gap length, number of turns/phase, number of stator

conductors, area of cross-section of the stator conductor for a 3-phase, 15 Kw, 400 Volts, 6 pole, 50 Hz,

970 rpm induction motor suitable for star delta starting. Assume specific electric loading and magnetic

loading as 45 tesla and 2300 A/m respectively. Ratio of core length to pole pitch is 0.85, full load

efficiency 0.88, power factor of the value 0.89, winding factor Kw=0.955 and the current density

delta=4.0 A/mm2

P=input(‘enter the output rating of the induction motor in KW--->’);

pf=input(‘enter the power factor of the motor--->’);

N=970; %speed of the motor in rpm

Bav=0.45; %specific magnetic loading in Wb/m^2

El=400; %voltage rating in volt

Lbytaw=0.85; %ratio of core length to pole pitch

Li=400;

f=50; %supply frequency

eff=0.88; %efficciency

Kw=0.955; %winding factor

ac=2300; %specific electric loading in A/m

Ki=0.9; %assume iron

delta=4;

p=6;

input=p/(eff*pf);

CO=1.11*pi^2*Bav*ac*Kw*10^-3;

Ns=2*f/p;

Volume=imput/(CO*Ns);

Lbyd=(Lbytaw*pi)/p;

D=(volume/Lbyd)^(1/3);

L=Lbyd*D;

Lg=(0.2+2*sqrt(D*L));

Es=El;

Phaim=(Bav*pi*D*L)/p;

Ts=Es/(4.44*f*phaim*Kw;

Ts=round(Ts);

Zs=6*Ts;

Ls=(p*10^3)/(3*El);

For qs=2:5

Ss=3*p*qs;

Yss=(pi*D)/Ss*10^-2);

If Yss>1.01&Yss<1.5;

Ss=Ss;

Yss=Yss;

Zss=round(Zs/Ss);

Zs=Zss*Ss;

Ts=Zs/6;

end

end

ls=(p*10^3)/(3*El);

as=ls/delta;

disp(……………….DESIGN OUTPUT………………………)

disp(the diameter of the motor in meter is……..>)

disp(D);

disp(the length of the motor in meter…..>)

disp(L);

disp(the length of the air gap in mm is……..)

disp(g)

disp(the no of stator turn/phase is….>)

disp(Ts)

disp(the no of stator slot is….>)

disp(Ss)

disp(the cross-sectonal area of the stator conductor in mm.sq .is……>)

disp(as)

enter the output rating of the induction motor in KW………….>15

enter the power factor of the motor….89

…………………………DESIGN OUTPUT…………………………………..

The diameter of the motor in meter is………>

0.4569

The length of motor in meter …..>

0.2033

The length of the air gap in mm is…..>

0.8096

The no of stator turn/phase is…,..>

86

The no of stator slot is……..>90

The cross-sectional area of the stator conductor in mm.sq. is….>

3.1250