Electric Circuits and Networks

7.4 AVERAGE POWER IN PERIODIC WAVEFORMS

The following points emerge from the discussion on instantaneous power in Sect. 7.3.

• Instantaneous power delivered to an element is a non-constant function of time in general.
• If the voltage across the element and the current through the element are periodic waveforms with period T and zero average value over a cycle period, the instantaneous power will be a periodic waveform with period 0.5T and may have a non-zero average value over its cycle period of 0.5T.
• The energy delivered to the element will also be a function of time. The value of total energy delivered to the element at the end-of-cycle points will fall on a straight line with a slope equal to the average value of instantaneous power waveform ...