A three phase star connected 400v sohz4 pole induction motor...

A three-phase star-connected 400V, 50Hz, 4-pole induction motor has the following per phase parameters in ohms referred to the stators: R1 = 0.15, X1 = 0.45, R2 = 0.12, X2 = 0.5. Draw the equivalent circuit and compute the stator current and power factor when the motor is operated at rated voltage and frequency with Î´ = 0.04.

Transcript

00:01 In this question we have the value of a supply voltage, vl which is equal to 400 watt.

00:07 Then the frequency f which is equals to 50 hertz.

00:11 Next we have the number of poles that is p which is equals to 4.

00:17 Now we can also write down the equation for the synchronization speed that is ns which is equals to 120 f divided by p so here we have this 120 frequency that is a 50 divided by number of poles that is 4 so on a simplification of it we get the value of ns which is equals to 1 5 or 0 this is in rpm now we also have the sleep s which is equals to 0 .04 we can write down the value of resistor r1 which is equal to point of 15 om, then x1 which is equals to x2, which is equals to 0 .45 om, r2 which is equal to 0 .12 oom, and xm, which is equal to 28 .5 oom.

01:20 Now let's first to draw the circuit.

01:23 So this is the equivalent.

01:29 Equivalent circuit, circuit referred to stator.

01:42 Now we can write down the equation of r -dash -l which is equal to r2 multiplied by 1 divided by s minus of 1.

01:51 Now let's further simplify it.

01:54 So it becomes 0 .12 multiplied by 24.

01:58 So on a further simplification we get the value of a rl dash which is equal to 2 .88 o.

02:07 Then current i note which is equal to v, ph divided by xm.

02:14 So it becomes 400 divided by root 3 divided by this xm we have 28 .5.

02:26 So on a simplification, here this xm has a vector j.

02:31 So it becomes minus 8 .103j.

02:39 Now on a further simplification, we can find out the value of i2 dash, that is the vp divided by r note 1 plus rl dash multiplied by plus jx01.