# T-equivalent

Discussion in 'Homework Help' started by mo2015mo, May 16, 2013.

1. ### mo2015mo Thread Starter Member

May 9, 2013
157
1
Hi guys,

Determine whether the given solution of attached question is correct OR not ??

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2. ### t_n_k AAC Fanatic!

Mar 6, 2009
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I'd say incorrect.

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May 9, 2013
157
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Why ? ? ? ?

4. ### mo2015mo Thread Starter Member

May 9, 2013
157
1
mutual inductance is negative ??

5. ### t_n_k AAC Fanatic!

Mar 6, 2009
5,448
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I'm not sure what you mean.

In any event I believe the answer is incorrect - according to my worked analysis.

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6. ### mo2015mo Thread Starter Member

May 9, 2013
157
1
how u analyse the circuit ? tell me ..

7. ### t_n_k AAC Fanatic!

Mar 6, 2009
5,448
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It usually works the other way on the homework forum. You show your working first, then I may show you mine or (better still) offer some suggestions on how you might go about finding the solution.

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8. ### mo2015mo Thread Starter Member

May 9, 2013
157
1
really i founded the solution under the attached question But u told me it's incorrect

According to my information i know when the mutual inductance (M) is minus,
added M to L1 and L2

9. ### The Electrician AAC Fanatic!

Oct 9, 2007
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10. ### mo2015mo Thread Starter Member

May 9, 2013
157
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My solution method

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11. ### The Electrician AAC Fanatic!

Oct 9, 2007
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Consider the original circuit. If you apply a "positive" AC voltage to the V1 terminals, you get a "positive" voltage at the V2 terminals (no phase inversion, in other words).

But, your equivalent has a shunt element of -2H. Since the voltage that appears at the open-circuited V2 terminals is just the voltage across that shunt element, you will get phase inversion due to the minus sign, so for that reason alone your equivalent is not right.

Re-examine how you formed your equations.

12. ### mo2015mo Thread Starter Member

May 9, 2013
157
1
I tried to solve it as attached fig But still the same problem

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13. ### The Electrician AAC Fanatic!

Oct 9, 2007
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Your second equation should be -V2 = 5 s I2 - 2 s I1

Try reversing the direction of I2 and see what equations you get, both for the original transformer and for the tee equivalent with 3H, 2H and 3H.

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