Questions: Q1: Verify that the average power generated equals the average power absorbed using the simulated values in Table 7-2. Q2: Verify that the reactive power generated equals the reactive power absorbed using the simulated values in Table 7-2. Q3: Why it is important to correct the power factor of a load? Q4: Find the ideal value of the capacitor theoretically that will result in unity power factor. Vs pp (V) VRIPP (V) VRLC PP (V) AT (μs) T (us) 8° pf Simulated 14 8.523 7.84 84.850 1000 29.88 0.866 Measured 14 8.523 7.854 82.94 1000 29.85 0.86733 Table 7-2 Power Calculations Pvs (mW) Qvs (mVAR) PRI (MW) Pay (mW) Qt (mVAR) Qc (mYAR) Simulated -12.93 -7.428 9.081 3.855 12.27 -4.84 Calculated -12.936 -7.434 9.083 3.856 12.32 -4.85 Part II: Power Factor Correction Table 7-3 Power Factor Correction AT (us) 0° pf Simulated 0 0 1 Measured 0 0 1 OrCAD Simulation (Pre-Lab) Simulate the circuit shown in Figure 7-2 in OrCAD with the following steps. w R1 L1 C1 R3 Figure 7-2: Circuit Diagram Part I: Sinusoidal Steady-State Power Calculations 1. Start OrCAD. w 2. = Add the circuit clements R₁ 1 kn; R = 2 kn; L = 100 mH; and C = 0.1 uF. 3. Add a 1 kHz sinusoidal voltage source (Vin) as follows, Parameter VOFF Description Value Offset voltage (volts); 0 VAMPL 1 Amplitude (volts); Vp FREQ = Frequency (hertz). 1 kHz 4. 5. Note: the voltage level of the waveform will be given by your lab instructor. Add the ground and connect the circuit components together with wires. Simulate the circuit using 'Time Domain (Transient)' analysis as follows, 6. 7. Run To Time : Include the first five cycles (5 x T). Maximum Step Size : 1 us. Skip initial transient bias point calculation (SKIPBP). Plot the source voltage Vs and the resistor voltage VR, using the 'Voltage Probe' and plot the parallel combination voltage VRLC = VS - VR, using the 'Differential Voltage Probe'. Measure the voltages Va, and VLC, and the period T using the 'cursor'. ENGR 207 | EE Fundamentals Lab | Fall 2024 12024 3 8. Measure the time shift AT between Vs and VR, using the 'cursor'. 9. Calculate the phase shift 0° between Vs and VR, AT 0° = =- x 360° T 10. Calculate the power factor pf = cos(0) and indicate if it is lags, leads, or unity. 11. Complete the simulated values in Table 7-1 in the datasheet. 12. Complete the power calculations in Table 7-2 in the datasheet using the simulated values in Table 7-1. Part II: Power Factor Correction 13. Change the capacitor value to C = 0.25 µF 14. Resimulate the circuit as in stop (5). 15. Redo the steps (8) to (10). 16. Complete the simulated values in Table 7-3 in the datasheet. 3

Questions: Q1: Verify that the average power generated equals the average power absorbed using the simulated values in Table 7-2. Q2: Verify that the reactive power generated equals the reactive power absorbed using the simulated values in Table 7-2. Q3: Why it is important to correct the power factor of a load? Q4: Find the ideal value of the capacitor theoretically that will result in unity power factor. Vs pp (V) VRIPP (V) VRLC PP (V) AT (μs) T (us) 8° pf Simulated 14 8.523 7.84 84.850 1000 29.88 0.866 Measured 14 8.523 7.854 82.94 1000 29.85 0.86733 Table 7-2 Power Calculations Pvs (mW) Qvs (mVAR) PRI (MW) Pay (mW) Qt (mVAR) Qc (mYAR) Simulated -12.93 -7.428 9.081 3.855 12.27 -4.84 Calculated -12.936 -7.434 9.083 3.856 12.32 -4.85 Part II: Power Factor Correction Table 7-3 Power Factor Correction AT (us) 0° pf Simulated 0 0 1 Measured 0 0 1 OrCAD Simulation (Pre-Lab) Simulate the circuit shown in Figure 7-2 in OrCAD with the following steps. w R1 L1 C1 R3 Figure 7-2: Circuit Diagram Part I: Sinusoidal Steady-State Power Calculations 1. Start OrCAD. w 2. = Add the circuit clements R₁ 1 kn; R = 2 kn; L = 100 mH; and C = 0.1 uF. 3. Add a 1 kHz sinusoidal voltage source (Vin) as follows, Parameter VOFF Description Value Offset voltage (volts); 0 VAMPL 1 Amplitude (volts); Vp FREQ = Frequency (hertz). 1 kHz 4. 5. Note: the voltage level of the waveform will be given by your lab instructor. Add the ground and connect the circuit components together with wires. Simulate the circuit using 'Time Domain (Transient)' analysis as follows, 6. 7. Run To Time : Include the first five cycles (5 x T). Maximum Step Size : 1 us. Skip initial transient bias point calculation (SKIPBP). Plot the source voltage Vs and the resistor voltage VR, using the 'Voltage Probe' and plot the parallel combination voltage VRLC = VS - VR, using the 'Differential Voltage Probe'. Measure the voltages Va, and VLC, and the period T using the 'cursor'. ENGR 207 | EE Fundamentals Lab | Fall 2024 12024 3 8. Measure the time shift AT between Vs and VR, using the 'cursor'. 9. Calculate the phase shift 0° between Vs and VR, AT 0° = =- x 360° T 10. Calculate the power factor pf = cos(0) and indicate if it is lags, leads, or unity. 11. Complete the simulated values in Table 7-1 in the datasheet. 12. Complete the power calculations in Table 7-2 in the datasheet using the simulated values in Table 7-1. Part II: Power Factor Correction 13. Change the capacitor value to C = 0.25 µF 14. Resimulate the circuit as in stop (5). 15. Redo the steps (8) to (10). 16. Complete the simulated values in Table 7-3 in the datasheet. 3

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter2: Fundamentals

Section: Chapter Questions

Problem 2.1MCQ: The rms value of v(t)=Vmaxcos(t+) is given by a. Vmax b. Vmax/2 c. 2Vmax d. 2Vmax

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