[SOLVED] DC link capacitor for H-Bridge

[--BawA--]

how to calculate the value of capacitor that should be put on DC bus of the H-Bridge? this H-Bridge will be utilized to design a single phase inverter of rating 500VA ,220V/50Hz
H-Bridge is driven through SPWM of carrier 16KHz and a fundamental frequency of 50Hz.

also which type of capacitor should be used ?

 

[--BawA--]

is there any advantage of using metallized polypropylene film capacitor over an Electrolytic capacitor ?

 

[rusty81]

Yes, one over all is the lower ESR (low dissipation), and lower leakage current due to the electrolite that don't have film capacitors.
Also an electrolytic capacitor is less lasting in time than a film capacitor.

 

[FvM]

A single phase inverter is loading the DC bus with 100 Hz ripple current, the acceptable ripple voltage determines the minimal bus capacitance, presumed you don't want to pass the ripple current to the primary DC/DC converter. Practically only electrolytic capacitors can provide the required capacitance with small form factor.

Film capacitors may be additionally wanted to absorb the switching frequent current, reduce ESR losses and bus series inductance.