By understanding the fundamental laws of circuit theory: The Ohm's Law and the Kirchhoff"s Laws, we are now applying those understandings in this type of analysis --The Nodal Analysis.
Actually there are two techniques for circuit analysis: the Nodal Analysis which is based on KCL and the Mesh Analysis which is based on KVL. Ohm's Law is still used in this analysis.
In this lesson we will be focusing our minds in nodal analysis. (Nodal Analysis without Voltage Source).
From the word 'nodal', Nodal Analysis is a general procedure for analyzing circuits using nodal voltages as the circuit variables. So you must be familiar what node is. If not, you can check our previous lesson about nodes (in lesson two) before proceeding in this lesson.
It is a tough battle against this but let's take it slow...slowly but surely. So lets start? Shall we?
Actually there are two techniques for circuit analysis: the Nodal Analysis which is based on KCL and the Mesh Analysis which is based on KVL. Ohm's Law is still used in this analysis.
In this lesson we will be focusing our minds in nodal analysis. (Nodal Analysis without Voltage Source).
From the word 'nodal', Nodal Analysis is a general procedure for analyzing circuits using nodal voltages as the circuit variables. So you must be familiar what node is. If not, you can check our previous lesson about nodes (in lesson two) before proceeding in this lesson.
It is a tough battle against this but let's take it slow...slowly but surely. So lets start? Shall we?
Nodal Analysis Without Voltage Source:
•Make use of node voltages as circuit variables.
STEPS IN DETERMINING THE NODE VOLTAGES:
a.) Select a node as the reference node. A reference node is a node with zero potential or V = 0V.
b.) Assign voltages v1, v2, v3, vn-1 to the remaining n-1 nodes. That will be our non-reference node. The voltages are referenced with respect to the reference node.
c.) Apply KCL to each of the n-1 non-reference nodes. Using Ohm's Law to express the branch currents in terms of node voltages. You need to assign currents and assume it's direction.
d.) Solve to determine the unknown node voltages. Use substitution method or Cramer's Rule to obtain the unknown node voltages.
•Make use of node voltages as circuit variables.
STEPS IN DETERMINING THE NODE VOLTAGES:
a.) Select a node as the reference node. A reference node is a node with zero potential or V = 0V.
b.) Assign voltages v1, v2, v3, vn-1 to the remaining n-1 nodes. That will be our non-reference node. The voltages are referenced with respect to the reference node.
c.) Apply KCL to each of the n-1 non-reference nodes. Using Ohm's Law to express the branch currents in terms of node voltages. You need to assign currents and assume it's direction.
d.) Solve to determine the unknown node voltages. Use substitution method or Cramer's Rule to obtain the unknown node voltages.
Okay, here is an example circuit...let us find the unknown node voltages.
First thing we need to do is to do the first and second steps in determining the node voltages which is to find the reference node and the non-reference nodes.
First thing we need to do is to do the first and second steps in determining the node voltages which is to find the reference node and the non-reference nodes.
Next we will assign where to label or to put v1, v2, Vn-1 in the non-reference nodes. In our circuit we have three non-reference nodes we can label it as v1, v2, and v3. Also we will assign and assume the current and the directions... As seen in this circuit below.
In our circuit we have two independent current sources labeled as Ia and Ib. Three non-reference nodes labeled as v1, v2, and v3. And four currents labeled from I1 to I4. Since we have labeled it we will now find the unknown node voltages...