1. Lecture 31 EEE 302 Electrical Networks II Dr. Keith E. Holbert Summer 2001

2. Lecture 32 Superposition Procedure 1.For each independent voltage and current source (repeat the following): a) Replace the other independent voltage sources with a short circuit (i.e., V = 0). b) Replace the other independent current sources with an open circuit (i.e., I = 0). Note: Dependent sources are not changed! c) Calculate the contribution of this particular voltage or current source to the desired output parameter. 2.Algebraically sum the individual contributions (current and/or voltage) from each independent source.

3. Lecture 33 Class Example Extension Exercise E8.15

4. Lecture 34 Source Transformation VsVs + - RsRs IsIs RsRs

5. Lecture 35 Class Example Extension Exercise E8.16

6. Lecture 36 Thevenin/Norton Analysis 1. Pick a good breaking point in the circuit (cannot split a dependent source and its control variable). 2. Thevenin: Compute the open circuit voltage, V OC. Norton: Compute the short circuit current, I SC. For case 3(b) both V OC =0 and I SC =0 [so skip step 2]

7. Lecture 37 Thevenin/Norton Analysis 3. Compute the Thevenin equivalent resistance, R Th (or impedance, Z Th ). (a) If there are only independent sources, then short circuit all the voltage sources and open circuit the current sources (just like superposition). (b) If there are only dependent sources, then must use a test voltage or current source in order to calculate R Th (or Z Th ) = V Test /I test (c) If there are both independent and dependent sources, then compute R Th (or Z Th ) from V OC /I SC.

8. Lecture 38 Thevenin/Norton Analysis 4. Thevenin: Replace circuit with V OC in series with R Th, Z Th. Norton: Replace circuit with I SC in parallel with R Th, Z Th. Note: for 3(b) the equivalent network is merely R Th (or Z Th ), that is, no voltage (or current) source. Only steps 2 & 4 differ from Thevenin & Norton!

9. Lecture 39 Independent Sources (Thevenin) Circuit with independent sources R Th V oc + - Thevenin equivalent circuit

10. Lecture 310 No Independent Sources Circuit without independent sources R Th Thevenin equivalent circuit

11. Lecture 311 Class Example Extension Exercise E8.17