Average Value

 

Average Value

Definition:
The average value of an AC signal over one complete cycle is zero for a pure sinusoidal wave because the positive and negative halves cancel each other out. However, the average value is often taken over a half-cycle to provide a non-zero figure, especially in rectified AC circuits.

For a sinusoidal waveform, the average value over one half-cycle is:

$$V_{\text{avg}} = \frac{2V_{\text{max}}}{\pi}, \quad I_{\text{avg}} = \frac{2I_{\text{max}}}{\pi}$$

Example:
For a sinusoidal voltage with $V_{\text{max}} = 100V$, the average value over a half-cycle is:

$$V_{\text{avg}} = \frac{2 \times 100}{\pi} \approx 63.7V$$