Thevenin equivalent of a network

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bishshoy007
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Homework Statement



The question is to find the Thevenin equivalent of the network across the terminals a,b.
The circuit is as follows:--
pbxqs.jpg

The solution is Zth = 12.166 angle(136.3*)ohm and Vth = 7.35 angle(72.9*)
I can find out the Vth, that's easy. But I can get the Zth right coz there is the dependent source. Please help ! I have tried almost 50 times, with different methods.

Homework Equations



The two basic laws (comon everyone knows this):--

Kirchoffs' Voltage law = sum of voltages in a loop = 0
Kirchoffs' node law = sum of current through a node = 0

The Attempt at a Solution



k9yk9s.jpg

First I have lumped all series reactances.
At node 1 :--
5 + 0.2V0 = -V0/(8+4j)
Solving V0 = -16.22 - 2.7j

Now writing the KVL for the loop :--
Vth + V0 - (4 - 2j)*0.2-V0 = 0
Solving we get Vth = 2.16 + 7.027j = 7.35 angle(72.89*)

For the Zth I have tried solving by adding a dummy current source at the terminals a,b. It didnt work. Then i tried adding a voltage source across the (8 + 4j) impdedance. Still I couldn't get the answer correct.
 
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You can calculate the Norton current In.
Zth = Vth/In.
 
Yes I haven't tried that. But still I would like to have the thevenin voltage. Any mind helping me, with the solution.
 
There is a typo in the equation of the loop, otherwise it is correct. I have not checked your calculations.

The equation should be

Vth + Vo - (4-2j)*0.2*Vo = 0

You have posted:

Vth + Vo - (4-2j)*0.2-Vo = 0
 
Thanks buddy. It works like a charm.