Voltage drop over dependent current source?

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In a circuit with three meshes, the presence of a dependent current source (CCCS) can affect mesh current equations due to potential voltage drops. It is suggested to either convert the current source and its parallel resistor into a Thevenin equivalent voltage source or introduce a new variable for the voltage drop across the current source. The first method simplifies the mesh equations by reducing the circuit to two loops, while the second method requires an additional equation to account for the dependency. The discussion confirms that Thévenin and Norton equivalents can be used with dependent sources, provided the dependencies are maintained. Proper handling of the dependent source is crucial for accurate mesh current analysis.
Inertigratus
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I have a circuit with 3 meshes for which I have to find the mesh currents, and I have.
However, I just thought that there might be a voltage drop over the dependent current source in the circuit, which would change the mesh current equations.
The CCCS is shared by two meshes.
When I did the calculations I simply ignored the CCCS.
Any ideas?
 
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Inertigratus said:
I have a circuit with 3 meshes for which I have to find the mesh currents, and I have.
However, I just thought that there might be a voltage drop over the dependent current source in the circuit, which would change the mesh current equations.
The CCCS is shared by two meshes.
When I did the calculations I simply ignored the CCCS.
Any ideas?

Can you post the circuit diagram?
 
Sure, http://img692.imageshack.us/img692/7081/namnlskei.jpg
I'm not asking for the solution, just wondering what I should do with the dependent source when writing the mesh equations?
 
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Two suggestions. First, you could convert the current source and the 4R resistor in parallel with it to a Thevenin equivalent voltage source. That would let you write the KVL mesh equations without worrying about mystery voltages. It would also reduce the circuit to just two loops.

Second, you could introduce a new variable, say vx, which is the voltage drop across the current source, and one new equation (with a new variable you need another equation). This equation would be the additional constraint on the mesh currents implied by the current source, namely i2 - i3 = k*i1.

attachment.php?attachmentid=38884&stc=1&d=1316101327.gif


I think that the first suggestion would be simpler. Note that the third mesh current i3 is strictly dependent upon the voltage vx via Ohm's Law with the 4R resistor.
 

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I see, thanks!
So it's possible to use Thévenin and Norton equivalents when the sources are dependent as well?
 
Inertigratus said:
I see, thanks!
So it's possible to use Thévenin and Norton equivalents when the sources are dependent as well?

Sure, as long as you maintain the dependencies through the calculations.
 

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