1. 1 Figure 7.1, 7.2 Chapter 7: AC PowerCurrent and voltage waveforms for illustration of AC power

2. 2 Instantaneous and Average Power

3. 3 Instantaneous Power Calculations

4. 4 Figure 7.3 Instantaneous and average power dissipation corresponding to the signals plotted in Figure 7.2

5. 5 Instantaneous Power power current voltage wt magnitude Instantaneous power has twice the frequency of the voltage or current

6. 6 RMS Value It is customary in AC power analysis to employ the RMS value of the AC voltage and currents in the circuit (Read Section 4.2).

7. 7 Impedance Triangle Vs jX R X Z R 

8. 8 Power Factor The phase angle of the load impedance plays a very important role in the absorption of power by a load impedance. The average power dissipated by an AC load is dependent on the cosine of the angle of the impedance. The term cos (  ) is referred as the power factor (pf). The power factor is equal to 0 for purely inductive or capacitive load. The power factor is equal to 1 for a purely resistive load.

9. 9 Complex Power QS P av  Reactive Power Real Power Apparent Power

10. 10 Table 7.2

11. 11 Figure 7.16, 7.17

12. 12 Figure 7.18, 7.19, 7.20 Power factor correction