In this example the inductance is placed on the AC side of the rectifier. Compared to the case of a single DC side inductor, this circuit instead requires 3 AC inductors. By changing the value of the inductor the level of distortion changes in the AC current waveforms. For larger values of inductance, the AC current has a more sinusoidal shape and less distortion. However, looking at the true power factor curve on the graph it can be seen that the power factor reaches a maximum at around 5% inductance, before reducing for larger inductance value. This reduction is caused by the AC inductors introducing more phase lag in the fundamental current waveform. In this case too much inductance is a bad thing. 

Using a low inductor value causes the distortion and output voltage ripple to increase, and the input current becomes discontinuous.

• Shift the operating point of the 3-phase rectifier by dragging the red line on the waveforms. Notice how the current commutates between the different diodes connected to each of the phases as you move the line. At certain points you find that the current is flowing simultaneously in 3 diodes, at what point does this occur and why?
• The value of the 3 AC side inductors can be simultaneously adjusted by dragging the red bar on the top inductor. Notice how the inductor value changes the current waveform shape from a very peaky, discontinuous current to a more continuous, flatter current waveform shape. This also changes the harmonic composition of the current as seen in the spectrum.