Buck DC-DC converter

[sabu31]

Hello everyone,

I am trying to design a buck converter with following ratings (I/p 700V and O/p 90-140V, Output Power=10kW). The efficiency needs to be greater than 96%. I am confused regarding the topology ideal for this type of system. Whether it should be LLC resonant or Phase shifted Full bridge. If there is any application note or papers regarding this please let me. Thanking you.

 

[Easy peasy]

Series resonant is a good choice here for 10kW, phase shift full bridge, we have done these to 16kW at 350V out, 1kV in.

 

[sabu31]

Thanks for the reply.
But will high current at output side lead to excessive loss in secondary side of LLC resonant converter which contains only diodes.

 

[Easy peasy]

115A is pretty easy - you can use 600V Si or SiC diodes in a centre tapped output, ~ 115W of losses, or go for a full bridge and put Si or SiC or GaN fets across the diodes to reduce rectifying losses...