Transformer saturation in SMPS
Transformer saturation in SMPS
(OP)
Push-pull or H-Bridge converter in voltage mode control may suffer from xfmr saturation. H-bridge can use a DC-blocking cap to eliminate xfmr saturation. However at low source voltage and high current that is expensive. Are there better ways to assure non-saturation? Maybe via current sensing? But how does that affect the operation of the H-bridge? Noise? chaos?





RE: Transformer saturation in SMPS
Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Transformer saturation in SMPS
Thanks for the reply anyway. I'll keep searching.
RE: Transformer saturation in SMPS
Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Transformer saturation in SMPS
Should be symetrical. I've had the Drain source cap.
increase significantly on an h-bridge do to traces
sitting on top of each other. Also you can increase
your dead time. Noise can also cause inbalances.
Make shure the CT(osc. cap.) is as close to the pins
as posible and leads as short as posible. Most manufacturers
put the ct and rtn next to each other.
These should help, but current mode is probably the best.
Searh on FLUX WALKING TRANSFORMERS. I got a lot of hits.
RE: Transformer saturation in SMPS
RE: Transformer saturation in SMPS
This may be due to your protoype having an even load (simple resistive load maybe) and large filtering of the pulse-width (combined with voltage-mode control) so that it doesn't change rapidly. If the pos & neg PW's are about the same, a steady offset of the BH curve will result (and it'll get as big as it needs to be) so that the offset current multiplied by the impedances will correct any small imbalances of your driver.
RE: Transformer saturation in SMPS