Nodal Analysis w/ Controlled Sources

AI Thread Summary
The discussion focuses on solving for voltages V1, V2, and V3 using nodal analysis with controlled sources. Key equations derived include KCL at various nodes and a supernode equation, which incorporates the relationship between currents and voltages. There is confusion regarding the setup of these equations, particularly the equivalence of certain equations and the role of constraint equations. The current through the controlled source is expressed in terms of the voltages at the nodes, leading to a rearrangement that forms a new equation. Overall, the thread emphasizes the importance of correctly applying KCL and KVL in the context of nodal analysis.
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Homework Statement


Find V1, V2 and V3.

Homework Equations


Nodal Analysis
Supernode Equation
Capacitance = 1/R
KCL & KVL

The Attempt at a Solution


KCL @ node 0: Ic = v2(-G1) +v3(-G3)
Node 1: Ic + I1 +v3(G2+G3) +V2(-G3) = 0 (subbing in Ic)
v2(G1+G3) + v3(g-3) = I1....Equation (1)

Node 2: v2(G1+G3) +v3(-G3) - I1 = 0...Equation (2)

Node 3: Same as equation 1

KVL @ supernode: -Hm*IC +V3-V2=0

I'm confused on how the equations were setup in the image.
 

Attachments

  • Node Voltage Problem.png
    Node Voltage Problem.png
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The first equation in the image is the same as what you've called equation 2. It's just the application of KCL to node 2.

The second equation in the image is a constraint equation; it's setting V1 equal to zero.

The third equation in the image is found like this:

The current in the Hm*Ic source is equal to the sum of the currents in R3 and R2, and is equal to G3*(v3-V2) + G2(V3).

Now, over at node 1, we have Ic + I1 + G3*(v3-V2) + G2(V3) = 0 or:

-Ic = G3*(v3-V2) + G2(V3) + I1

Equating the voltage across the Hm*Ic source we have V3 - V1 = Hm*Ic

giving V3 - V1 = -Hm*(G3*(v3-V2) + G2(V3) + I1)

or V3 - V1 + Hm*(G3*(v3-V2) + G2(V3) = -I1*Hm

Rearranging gives equation 3 in the image.
 

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