17-04-2013, 04:19 PM
Network Theorems
Network Theorems.ppt (Size: 229 KB / Downloads: 139)
Introduction
This chapter introduces important fundamental theorems of network analysis. They are the
Superposition theorem
Thévenin’s theorem
Norton’s theorem
Maximum power transfer theorem
Substitution Theorem
Millman’s theorem
Reciprocity theorem
Superposition Theorem
Used to find the solution to networks with two or more sources that are not in series or parallel.
The current through, or voltage across, an element in a network is equal to the algebraic sum of the currents or voltages produced independently by each source.
Since the effect of each source will be determined independently, the number of networks to be analyzed will equal the number of sources.
Thévenin’s Theorem
Thévenin’s theorem can be used to:
Analyze networks with sources that are not in series or parallel.
Reduce the number of components required to establish the same characteristics at the output terminals.
Investigate the effect of changing a particular component on the behavior of a network without having to analyze the entire network after each change.
Norton’s Theorem
Finding IN :
Calculate IN by first returning all the sources to their original position and then finding the short-circuit current between the marked terminals. It is the same current that would be measured by an ammeter placed between the marked terminals.
Conclusion:
Draw the Norton equivalent circuit with the portion of the circuit previously removed replaced between the terminals of the equivalent circuit.