Download Lab Exercise: Maximum Power Transfer and Thevenin's Theorem in ECET 1100 - Prof. Charles B and more Lab Reports Microelectronic Circuits in PDF only on Docsity! 4/2/2009 1 of 3 CLB Southern Polytechnic State University Electrical and Computer Engineering Technology ECET 1100 Laboratory Exercise No. 5 MPT and Thevenin’s Theorem Name_________________________________ Lab Section___________ Date_____________ Introduction In this exercise you will investigate Thevenin’s Theorem and Maximum Power Transfer. Pre-lab Calculations (To be completed before the laboratory session) For the circuit shown in Figure 1, calculate the Thevenin voltage, the Thevenin resistance, and the Norton current with respect to terminals T and H. The load resistor should be removed for these calculations. Determine the value of the load resistance RL that would provide maximum power to be transferred from the source. (Use the space below to show your results). Attach a copy of your calculations to your lab report. 2 kΩ + _12 V 1 kΩ 1 kΩ VTH (Calculated) = ____________ RTH (Calculated) = ____________ IN (Calculated) = ______________ Have your instructor verify your pre-lab calculations and results. Instructor Initials: _________ 4/2/2009 2 of 3 CLB Cautions • Do not energize a circuit until your instructor checks it. • Remove all power from a circuit before attempting to measure resistance in the circuit with an ohmmeter. Remember to disconnect the resistance from the circuit. • Remove all power before making changes in a circuit. • Record all data in ink. Do not erase. Make corrections by drawing a line through the incorrect data and write the correct data next to the deleted data. Procedure 1. Construct the circuit in Figure 1. Using a voltmeter, measure and record the Thevenin Voltage. (The load resistor should be removed for this measurement and the 12 V source should be verified.) VTH = __________________ 2. Using an ammeter, measure and record the Norton Current. (The load resistor should be removed for this measurement and the 12 V source should be verified.) IN = ____________________ 3. Remove the source and put a short in its place, then using an ohmmeter, measure and record the Thevenin resistance at terminals T and H. (The load resistor should be removed for this measurement.) RTH = ___________________ 4. Measure and record the terminal voltage and current associated with RL connected into the circuit, where RL is 470 Ω. (The 12 V source should be verified before the measurements are made.) VRL = ____________________ IRL = ____________________ 5. Replace RL with a decade resistor. In Table 1, neatly tabulate the load voltage VRL, load current IRL, and load power PRL for resistance values ranging from 1 kΩ to 2.6 kΩ in increments of 200 Ω, while making sure that the supply voltage remains constant at 12 V. Plot Load Power verses Load Resistance on Graph 1 of the next page. Accurately label the plot axes. Have your instructor check your results before proceeding to the next step. 6. Using the values measured in steps 1 and 2, construct the Thevenin equivalent circuit with the decade resistance box as the load. In Table 2, neatly tabulate the load voltage, load current, and load power for load resistance values ranging from 1 kΩ to 2.6 kΩ in increments of 200 Ω. Plot Load Power verses Load Resistance for the Thevenin circuit on the same plot created in step 5. Report Guide 1. From your plots, determine the load resistance that results in maximum power transfer to the load for both steps 5 and 6. Do the results confirm the Maximum Power Transfer Theorem? 2. Discuss any differences between your theoretical and measured results.
