Power Factor

Power Factor

In this lab we calculate the power factor of the series circuit above. We apply a 1 V @ 5 kHz sinusoidal signal through a resistor Rt, 1 mH inductor, and 9.7 Ω resistor (this includes inductor resistance).

We vary the Rt resistor three times, and their measured values are given on the first column on the board above. Next, using the measured resistances and inductance, we calculate the theoretical impedance Zth, current rms Irms, voltage of the load rms Vrms, We also calculate the average power of the load and the apparent load power. We calculate each of these as a phasor as shown above.

Here we see the graphs for Rt = 10.3 Ω. We can find the magnitudes directly from the graph and the phase angle by measuring the change in time, dividing by the period and multiplying by 360 degrees.

Now we see the graph for when Rt = 47.2 Ω. Again we can find the magnitudes and obtain the phase shifts just as done previously.

Finally we see the graph for Rt = 100.0 Ω. We use the same methods to calculate the magnitudes and phase angles.