T
treez
Guest
![Newbie level 1](/styles/images/ranks/alevel1.gif)
Hello,
We are trying to design a bi-directional, isolated SMPS FOR 7kW.
We tried it with a Full Bridge, which in reverse direction, is a “Current fed Full Bridge SMPS” (as in the attached LTspice simulation and schematic).
However, as the LTspice simulation shows, its operation is ruined by 1.5kv overvoltage spikes on the drains of the Power FETs. This is caused by the sudden change of current in the leakage inductance of the full bridge transformer.
The overvoltage ringing is at 500KHz, -too low a frequency to be able to easily snub out. [frequency is too near F(sw)]
Do you know if this Current fed Full Bridge is really workable?
We are trying to design a bi-directional, isolated SMPS FOR 7kW.
We tried it with a Full Bridge, which in reverse direction, is a “Current fed Full Bridge SMPS” (as in the attached LTspice simulation and schematic).
However, as the LTspice simulation shows, its operation is ruined by 1.5kv overvoltage spikes on the drains of the Power FETs. This is caused by the sudden change of current in the leakage inductance of the full bridge transformer.
The overvoltage ringing is at 500KHz, -too low a frequency to be able to easily snub out. [frequency is too near F(sw)]
Do you know if this Current fed Full Bridge is really workable?