The ripple factor is a dimensionless quantity that measures the amount of ripple content present in the waveform of a rectified output. It is defined as the ratio of the RMS value of the alternating current (AC) component in the rectified output to the average value of the rectified output. The ripple factor is denoted by the symbol γ and always has a value less than unity.

The ripple factor formula is defined in terms of the RMS value and the average value of the rectifier output. It is given as:

$$\Gamma =\frac{\sqrt{(I_{rms})^{2}-(I_{dc})^{2}}}{I_{dc}}=\frac{\sqrt{(V_{rms})^{2}-(V_{dc})^{2}}}{V_{dc}}$$

where:

• I’rms is the alternating component of load current
• V’rms is the alternating component of voltage
• Idc is the average value of the rectified output current
• Vdc is the average value of the rectified output voltage

The ripple factor plays a major role in describing the efficiency of any rectifier. It determines the quality of the rectified output, and less ripple factor in any circuit is preferred. The ripple factor is critical in determining the efficacy of rectifier output, and the lesser the ripple factor, the more effective the rectifier.