Chapter 12

1 / 33

# Chapter 12 - PowerPoint PPT Presentation

Chapter 12. Thevenin, Norton and Maximum Power Transfer Theorems. Thevenin’s Theorem. Why Thevenin’s Theorem is useful. What is Thevenin’s Theorem?.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

## PowerPoint Slideshow about 'Chapter 12' - meryle

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

### Chapter 12

Thevenin, Norton and Maximum Power Transfer Theorems

Thevenin’s Theorem
• Why Thevenin’s Theorem is useful
What is Thevenin’s Theorem?
• Everything in the original circuit, except the load, maybe replaced by an equivalent circuit. The equivalent circuit consists of a series combination of a voltage source and a resistance.
Steps to make a Thevenin Circuit

Write these on white board

Equivalent Thevenin Circuit

Now you can place any load in the circuit you want and the calculations are EASY!

.66mA

=10kΩ

Using the Thevenin Theorem

Determine VTH

Solving for VTH

10V

5V

VTH = VA – VB = 5V

Solving for RTH

What is the resistance from point a to b?

B

A

Turning Figure 12.15C into Figure 12.15D

10kΩ

9kΩ

10kΩ

3kΩ

Random Video of the Day
Norton’s Theorem
• Everything in the original circuit, except the load may be replaced by an equivalent circuit. The equivalent circuit consists of a parallel combination of a current source and a resistance.
What a Norton Circuit Looks Like

Norton

Resistance

Norton Current IN

2mA

Norton Shortcut
• There are a bunch of rules for how to calculate the Norton Current and Norton Resistance. However, a shortcut is to find the Thevenin Equivalent circuit and then convert it to a Norton
Other Circuit Analysis Techniques
• Besides using traditional circuit analysis using Ohm’s Law, or Superposition, Mesh Analysis, Thevenin’s Theorem, and Norton’s Theorem, there are other circuit analysis techniques. A couple include:
• Nodal Analysis and Millman’s Theorem

Do more hw problems from back of chap 12 (9, 10, 11, or 12) if time

Practice Problem
• In the following circuit solve for VTH, RTH, IN, RN, IL and VL
Another Practice Problem

Solve for VL using traditional Ohm’s Law technique, Mesh Analysis, and Thevenin Analysis

What load resistor would you use for the following circuit to have max power transferred?

?

What circuit analysis technique can we use to solve for this?

Thevenin’s Theorem. RTH = 5kΩ

I’ve checked this technique using Ohm’s law and it works. See following numbers:

5mW @ 5kOhm

4.94mW @ 4kOhm

4.96mW @ 6kOhm

Switches

SPST SPDT DPST DPDT