Circuit Solving Techniques: Nodal Analysis

Nodal Voltage Analysis

Nodal Voltage Analysis finds the unknown voltage drops around a circuit between different nodes that provide a common connection for two or more circuit components.

Understanding becomes easier when we take an example.

Let’s begin with this example. The question is to find I₃ from the diagram below.

In the above circuit, node D is chosen as the reference node and the other three nodes are assumed to have voltages, Va, Vb, and Vc with respect to node D.

NOTE: Voltage at node D, V_D = 0. It’s connected to zero potential.

We know that, I₁ + I₂ = I₃

So,

Substituting the values of V_a = 10v and V_c = 20v, we get:

We also know that, I₃= (V_b-V_d)/R , where R = 40Ω.

Hence,

*Think about the problem again, all we have done is finding the voltage at node B, finding the values of individual current is not at all tough after that.

That’s enough to understand Nodal Analysis and all that’s required now is to solve few more examples to gain confidence.

Authored By:- Cdt. Vikramaditya Patra, TMI