What is the ripple frequency of 415 V, 50 Hz, 3-phase full wave rectifier

Concept:

If input supplied frequency is ‘f’ then output ripple frequency of ‘n’ pulse converter is ‘nf’

Output ripple frequency = Number of pulse converter × input supply frequency

f0 = n⋅f

Consider 1-pulse converter (half-wave rectifier), the output voltage waveform is shown below (n = 1)

Consider 2-pulse converter (full-wave rectifier), the output voltage waveform is shown below (n = 2)

For 6 pulse converters (p = 6), the output voltage waveform is

Similarly, for n pulse converter output ripple frequency is ‘nf’.

Note: With the increase in pulse number, the output ripple decreases.

Calculation:

Given rectifier is a 3-phase Full-wave rectifier. It is a 6 pulse rectifier.

Therefore, the ripple frequency = 6f

Supply frequency = 50 Hz

Ripple frequency = 6 ×  50 = 300 Hz