# DGFH

Topics: Voltage source, Voltage drop, Current source Pages: 4 (869 words) Published: April 18, 2014
FHFHGFKYITJ;LKJHGFKFDLKJDSLKJHGFD.JKHGFDDRFRYRHFYHFDGCVGDVXVBVGDVMotivation 3.2 Nodal analysis.
3.3 Nodal analysis with voltage sources.
3.4 Mesh analysis.
3.5 Mesh analysis with current sources.
3.6 Nodal and mesh analysis by inspection.
3.7 Nodal versus mesh analysis.
￼Circuit Analysis I 2
￼3.1 Motivation (1)
If you are given the following circuit, how can we determine (1) the voltage across each resistor, (2) current through each resistor. (3) power generated by each current source, etc. What are the things which we need to know in order to determine the answers? Circuit Analysis I 3

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3.1 Motivation (2)
Things we need to know in solving any resistive circuit with current and voltage sources only: • Kirchhoff’s Current Laws (KCL) • Kirchhoff’s Voltage Laws (KVL)It provides a general procedure for analyzing circuits using node voltages as the circuit variables. ￼Example 1

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￼Circuit Analysis I 5
￼3.2 Nodal Analysis (2)
Steps to determine the node voltages:
1. Select a node as the reference node.
2. Assign voltages v1,v2,...,vn-1 to the remaining n-1 nodes. The voltages are referenced with respect to the reference node. 3. Apply KCL to each of the n-1 non-reference nodes. Use Ohm’s law to express the branch currents in terms of node voltages. 4. Solve the resulting simultaneous equations to obtain the unknown node voltages. Circuit Analysis I 6

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￼3.2 Nodal Analysis (3)
Example 2 – circuit independent current source only
￼Apply KCl at node 1 and 2
v1
v2
￼￼￼￼￼*Refer to in-class illustration, textbook, answer v1 = -2V, v2 = -14V Circuit Analysis I 7
3

￼3.2 Nodal Analysis (4)
Example 3 – current with dependant current source
￼￼*Refer to in-class illustration, textbook, answer v1= 4.8V, v2 = 2.4V, v3 = -2.4V ￼Circuit Analysis I 8
￼3.3 Nodal Analysis with Voltage Source (1)
Example 4 –circuit with independent voltage source
￼￼￼How to handle the 2V voltage source?
￼Circuit Analysis I 9
￼3.3 Nodal Analysis with Voltage Source...