matlab problem


aabbddlah
10-26-2009, 06:31 PM
Hello everyone

i v just joined the forum and i would like u to give me some sort of help in my induction motor project
i am using matlab to carry out the value for torque and then plot the torque Vs speed graph using matlab

so i am given the parameters
I2=5.42A
R2=.8Ω

to carry out the torque values for (rotor speeds(wr)=from 0-50rad/s)

knowing that slip=s=0 when wr=50rad/s
and slip=1 when wr=0

Torque=(3/wr)*(I2^2) * {R2(1-s)/s}
To sum up i want to produce a torque speed plot using matlab

i suppose that i can do that using for loop
i think that it is not hard but i am not that good in matlab

here is my little attempt

for I2=5.42

for R2=.8
for s=.02
torque=(3/wr)*{(i2)^2}*{(r/s)*(1-s)}

plz help!
torqueplot
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Sorry but I think that did not put the problem in the proper wayIn fact torque should be calculated for different speeds and slips
(Not only different values of speed!)
So
given
R2=.8ohm
Rt=1.2ohm
Lt=2.2ohm
L2=3 ohm
s = (ws-wr) / ws , where ws=synchronous speed and wr=rotor speed
i2=formula in photo
torque=(3./wr)*(I2^2)*(R2/s)*(1-s
Also current cannot be one constant value
It should be calculated accordingly to slip values, so for each slip value we should have a value for current
To sum up , I think that we should use for loop to carry out values of slip ,corresponding speed ,and corresponding current on a range of values to create the proper plot
If the code is correct we must end up with the graph shown in the attachment
I will be thankful if u would help me
Many thanks