Analysis of mesh and Node. Example problem on Mesh and Node

1. BE8251-Basic Electrical and
Electronics Engineering
MESH AND NODALANALYSIS

2. BRANCH
•That part or section of a circuit which located between two
junctions are called the branch.
•In a branch, one or more elements can be connected and they
have two terminals.
In the figure AB, BC,
CD,AD, BD are branches.

3. NODE
• A point or junction where two or more circuit’s elements
(resistor, capacitor, inductor etc) meeting point is
called Node.
• In other words, a point of connection between two or more
branches is known as a Node.
•
• In the fig the nodes are B,D

4. MESH
• A closed loop which contains no other loop within it is called
Mesh.
• In the figure the loops are A-B-D-A, B-C-D-B.

5. LOOP
A closed path in a circuit where more than two meshes can
occur is known as Loop
In simple words, It is a closed path in a circuit.
l = b – n + 1
l = no of loops
b = no of branches
n = no of nodes

6. Contd.,
In the figure the loops are A-B-D-A, B-C-D-B, A-B-C-D-A

7. MESH ANALYSIS
•Step 1 − Identify the meshes and label the mesh currents in
either clockwise or anti-clockwise direction.
•Step 2 − Observe the amount of current that flows through
each element in terms of mesh currents.
•Step 3 − Write mesh equations to all meshes. Mesh equation
is obtained by applying KVL first and then Ohm’s law.
•Step 4 − Solve the mesh equations obtained in Step 3 in
order to get the mesh currents.

8. EXAMPLE

14. NODALANALYSIS
Step: 1 - Identify all nodes.
Step: 2 - Choose a reference node. Identify it with reference
(ground) symbol.
Step: 3 - Assign voltage variables to the other nodes (these
are node voltages.)
Step: 4 - Write a KCL equation for each node (sum the currents
leaving the node and set equal to zero).
Step: 5 - Solve the system of equations from step 4.

15. EXAMPLE:

16. Solution:

20. Thank you