JAJU316G November 2016 – April 2020
The bus capacitor is responsible for removing the ripple on the DC voltage that can be caused by the draw of sinusoidal currents. The capacitor value and the DC bus ripple are related by Equation 12.
This equation is used to select the minimum DC bus capacitance value.
NOTE
The above outlined calculation may yield to over design of the capacitor. The capacitor sizing is more dependent on the load and the nature of current it draws. For three phase PFC the power ripple is fairly small as the input always has path to the output. Hence, please use the equation above for reference only and be aware that this will yield to overdesign.