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Verify Thevenin’s Theorem.....in Lab work....
The Islamia University of Bahawalpur University College of Engineering & Technology Department of Electrical Engineering EE211 Network Analysis 3rd Term (2nd Year) (LAB EXPERIMENT NO. 2) Name: _______________________________ Roll No. __________________ Signature: ____________________________ Date: ____________________ To Verify Thevenin’s Theorem Performance Objectives: Upon successful completion of this experiment student will be able to: Understand the concept of source transformation Implement Thevenin’s theorem on complicated circuits to simplify them Equipment Required: Bread Board Resistors (Select any three resistors and calculate their Thevenin equivalent resistance) DC Power Supplies Digital Multimeter R1 R3 a + VS R2 VTH RTH - b Figure 1 RTH c VTH d Figure 2 Prior Calculations: Consider the circuits in figure 1 and figure 2 and follow the steps given below: 1. Write down the values of the three resistors you have selected for figure 1: R1 = R2 = R3 = 2. Calculate the value of RTH which will be used in circuit of figure 2: RTH = 3. Write down the expression for the open terminal voltage Vab which is equal to VTH: VTH = 4. If a load resistor (RL1) of 1kΩ is inserted between terminals a and b, what will be the expression for the load current IL1? IL1 = 5. Write the expression for the power delivered to RL: PL1 = 6. If a load resistor (RL2) of 1kΩ is connected between terminals c and d in figure 2, what will be the expression for current through this resistor? IL2 = Procedure: 1. Connect the circuit given in figure 1 2. Insert a load resistor of 1kΩ between terminals a and b 3. By adjusting the value of Vs, measure VL1 and complete the table given below: V L1 Vs VL1 I L1 PL1 I L1 V L1 1k 0 2 4 6 8 10 12 14 16 Table 1 4. Now on the same board connect the circuit given in figure 2 5. Insert a load resistor of 1kΩ between terminals c and d 6. For each value of VS in table 1, calculate the value of VTH and complete the second column of table 2 given below 7. By adjusting the value of VTH, measure VL2 and complete the table 2: VL2 Vs VTH VL2 I L2 PL 2 I L 2 VL 2 1k 0 2 4 6 8 10 12 14 16 Table 2 8. Your measurements should show the following equalities: VL1 = VL2 IL1 = IL2 PL1 = PL2 Questions: 1. If VTH aVS ; calculate the average value of a VTH a VS 2. Write the expression for a in terms of R1, R2 and R3 a 3. If we set VS = 200V in circuit 1, what will be the value of VTH? VTH = 4. What should be the value of VS in circuit 1 to have VTH = -25V? VS = 5. If we replace R1 with a short circuit, what will be the value of a? a= 6. If we replace R2 with a short circuit, what will be the value of a? a= 7. What is possible maximum value of a? 8. What is possible minimum value of a? 9. If we replace R3 with a short circuit in figure 1, will power delivered to load resistor increase or decrease? 10. Convert the circuit in figure 2 to a Norton equivalent if VTH = 10V and RTH = 4kΩ IN = RN =