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http://img247.imageshack.us/img247/7035/problemso9.jpg [Broken]

Ok so I have to do mesh-current analysis and I think I'm doing it correctly but my answer doesn't match the one given. This has to be done using phasors.

I labeled my meshes from left to right 1, 2, and so on.

33.8 = 1I1 + j2I1 + 3(I1 - I2) + (-j5)(I1-I2)

33.8 = 1I1 + j2I1 + 3I1 - 3I2 - j5I1 + j5I2

33.8 = (4 - j3) I1 + (-3 + j5) I2

0 = j5(I1 - I2) - 3(I1 - I2) + 2(I2 - I3)

0 = j5I1 - j5I2 - 3I1 + 3I2 + 2I2 - 2I3

(mesh current with the VCCS)

I3 = -0.75 Vx

where

Vx = (-j5)(I1 - I2)

I3 = -0.75 * (-j5)(I1-I2)

I3 = j3.75(I1 - I2)

substituting into Mesh 2 equation:

0 = j5I1 - j5I2 - 3I1 + 3I2 + 2I2 - 2( j3.75 (I1 - I2) )

0 = j5I1 - j5I2 - 3I1 + 3I2 + 2I2 - j7.5(I1 - I2)

0 = j5I1 - j5I2 - 3I1 + 3I2 + 2I2 - j7.5I1 + j7.5I2

0 = -3I1 + (5+j2.5)I2

I know:

I put both mesh equations in a matrix and the answer isn't what it's displayed in that picture (I get

Am i missing something here? I'm thinking I'm approaching this totally wrong. I always have a hard time with Mesh analysis and always prefer Nodal over it... but I'm almost certain that it has something to do with the VCCS (voltage controlled current source) and my equations for it.

Ok so I have to do mesh-current analysis and I think I'm doing it correctly but my answer doesn't match the one given. This has to be done using phasors.

I labeled my meshes from left to right 1, 2, and so on.

**Mesh 1**:33.8 = 1I1 + j2I1 + 3(I1 - I2) + (-j5)(I1-I2)

33.8 = 1I1 + j2I1 + 3I1 - 3I2 - j5I1 + j5I2

33.8 = (4 - j3) I1 + (-3 + j5) I2

**Mesh 2**:0 = j5(I1 - I2) - 3(I1 - I2) + 2(I2 - I3)

0 = j5I1 - j5I2 - 3I1 + 3I2 + 2I2 - 2I3

(mesh current with the VCCS)

I3 = -0.75 Vx

where

Vx = (-j5)(I1 - I2)

I3 = -0.75 * (-j5)(I1-I2)

I3 = j3.75(I1 - I2)

substituting into Mesh 2 equation:

0 = j5I1 - j5I2 - 3I1 + 3I2 + 2I2 - 2( j3.75 (I1 - I2) )

0 = j5I1 - j5I2 - 3I1 + 3I2 + 2I2 - j7.5(I1 - I2)

0 = j5I1 - j5I2 - 3I1 + 3I2 + 2I2 - j7.5I1 + j7.5I2

0 = -3I1 + (5+j2.5)I2

I know:

*I*= I1I put both mesh equations in a matrix and the answer isn't what it's displayed in that picture (I get

*I*= I1 = 8.98021 angle -1.828).Am i missing something here? I'm thinking I'm approaching this totally wrong. I always have a hard time with Mesh analysis and always prefer Nodal over it... but I'm almost certain that it has something to do with the VCCS (voltage controlled current source) and my equations for it.

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